U.S. patent application number 11/707420 was filed with the patent office on 2007-09-06 for novel catalyst systems and a process for reacting chemical compounds in the presence of said catalyst systems.
Invention is credited to Julia Maria Muller, Oskar Nuyken, Werner Obrecht.
Application Number | 20070208206 11/707420 |
Document ID | / |
Family ID | 37969706 |
Filed Date | 2007-09-06 |
United States Patent
Application |
20070208206 |
Kind Code |
A1 |
Obrecht; Werner ; et
al. |
September 6, 2007 |
Novel catalyst systems and a process for reacting chemical
compounds in the presence of said catalyst systems
Abstract
New catalyst systems for metathesis reactions, in particular for
the metathesis of nitrile rubber, are provided.
Inventors: |
Obrecht; Werner; (Moers,
DE) ; Muller; Julia Maria; (Blaustein, DE) ;
Nuyken; Oskar; (Munchen, DE) |
Correspondence
Address: |
LANXESS CORPORATION
111 RIDC PARK WEST DRIVE
PITTSBURGH
PA
15275-1112
US
|
Family ID: |
37969706 |
Appl. No.: |
11/707420 |
Filed: |
February 16, 2007 |
Current U.S.
Class: |
585/645 ;
502/103; 502/150; 502/152; 502/162; 502/167 |
Current CPC
Class: |
B01J 31/0268 20130101;
B01J 31/2273 20130101; B01J 31/26 20130101; B01J 31/30 20130101;
B01J 31/0239 20130101; B01J 31/2278 20130101; C08G 61/08 20130101;
B01J 31/2265 20130101; B01J 31/2208 20130101; C08C 19/08 20130101;
C08C 19/02 20130101; C08C 2019/09 20130101 |
Class at
Publication: |
585/645 ;
502/150; 502/167; 502/162; 502/152; 502/103 |
International
Class: |
C07C 6/00 20060101
C07C006/00; B01J 31/00 20060101 B01J031/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 22, 2006 |
DE |
10 2006 008 520.5 |
Claims
1. A Catalyst system comprising a metathesis catalyst and one or
more salts of the general formula (I) K.sup.n+A.sup.z- (I) where K
is a cation with the exception of copper and A is an anion, where n
is 1, 2 or 3 and z is 1, 2 or 3.
2. The Catalyst system according to claim 1, wherein the cation or
cations K in the general formula (I) is/are lithium, sodium,
potassium rubidium, caesium, francium, beryllium, magnesium,
calcium, strontium, barium, aluminium, gallium, indium, thallium,
germanium, tin, lead, arsenic, antimony, bismuth, scandium,
yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum,
chromium, molybdenum, tungsten, manganese, technetium, rhenium,
iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel,
palladium, platinum, silver, gold, zinc, cadmium, mercury and also
all elements of the group of the rare earths, in particular cerium,
praseodynium and neodymium, or the elements of the actinides.
3. The Catalyst system according to claim 1, wherein the cation or
cations K in the general formula (I) is/are complex cations based
on nitrogen, phosphorus or sulphur, preferably tetralkylammonium,
tetraarylammonium, hydroxylammonium, tetraalkylphosphonium,
tetraarylphosphonium, sulphonium, anilinium, pyridinium,
imidazolium, guanidinium and hydrazinium cations and cationic
ethylenediamine derivatives.
4. The Catalyst system according to claim 3, wherein the cation or
cations K in the general formula (I) is/are
benzyldodecyldimethylammonium, didecyldimethylammonium,
dimethylanilinium,
N-alkyl-N,N-bis-(2-hydroxyalkyl)-N-benzylammonium,
N,N,N-triethylbenzolmethanaminium, O-methyluronium,
S-methylthiuronium, pyridinium, tetrabutylaammonium,
tetramethyluronium, tetracetylammonium, tetrabutylphosphonium,
tetraphenylphosphonium, diphenylguanidinium, di-o-tolylguanidinium,
butyldiphenylsulphonium or tributylsulphonium.
5. The Catalyst system according to claim 1 or 2, wherein the anion
or anions in the general formula (I) is/are selected from the group
consisting of halides, pseudohalides, complex anions, anions of
organic acids, aliphatic or aromatic sulphonates, aliphatic or
aromatic sulphates, phosphonates, phosphates, thiophosphates,
xanthogenates, dithiocarbamates and noncoordinating anions.
6. The Catalyst system according to claim 5, wherein the anion or
anions in the general formula (I) is/are fluoride, chloride,
bromide, iodide, triiodide, azide, cyamide, thiocyamide,
thiocyanate, interhalides, sulphite, sulphate, dithionite,
thiosulphate, carbonate, hydrogencarbonate, perthiocarbonate,
nitrite, nitrate, perchlorate, tetrafluoroborate,
tetrafluoroaluminate, hexafluorophosphate, hexafluoroarsenate,
hexafluoroantimonate, hexachloroantimonate, anions or organic
carboxylic acids having from 1 to 20 carbon atoms which are
saturated or monounsaturated or polyunsaturated, in particular
formate, acetate, propionate, butyrate, oleate, palmitate,
stearate, versatate, acrylate, methacrylate, crotonate, benzoate,
naphthalenecarbonate, oxalate, salicylate, terephthalate, fumarate,
maleate, itaconate and abietate, anthraquinone-2-sulphonate,
benzenesulphonate, benzene-1,3-disulphonate, decane-1-sulphonate,
hexadecane-1-sulphonate, hydroquinonemonosulphonate,
methyl-4-toluenesulphonate, naphthalene-1-sulphonate,
naphthalene-1,5-disulphonate, tosylate, mesylate, dodecylsulphate,
alkylbenzenesulphates, vinylphosphonate, ethylphosphonate,
butylphosphonate, cetylphosphonate, dibutylphosphate,
dioctylphosphate, dibutyldithiophosphate, dioctylthiophosphate,
ethylxanthogenate, butylxanthogenate, phenylxanthogenate,
benzylxanthogenate, dimethyldithiocarbamate,
diethyldithiocarbamate, dibutyldithiocarbamate,
dibenzyldithiocarbamate, tetrakis[pentafluorophenyl]borate,
pentakis[pentafluorophenyl]phosphate,
tetrakis[3,5-trifluoromethylphenyl]borate,
pentakis[3,5-trifluoromethylphenyl]phosphate or
pentakis[pentafluorophenyl]cyclo-hexadienyl anion.
7. The Catalyst system according to claim 1, 2 or 5, wherein
compounds of the general formula (A), ##STR31## where M is osmium
or ruthenium, the radicals R are identical or different and are
each an alkyl, preferably C.sub.1-C.sub.30-alkyl, cycloalkyl,
preferably C.sub.3-C.sub.20-cycloalkyl, alkenyl, preferably
C.sub.2-C.sub.20-alkenyl, alkynyl, preferably
C.sub.2-C.sub.20-alkynyl, aryl, preferably C.sub.6-C.sub.24-aryl,
carboxylate, preferably C.sub.1-C.sub.20-carboxylate, alkoxy,
preferably C.sub.1-C.sub.20-alkoxy, alkenyloxy, preferably
C.sub.2-C.sub.20-alkenyloxy, alkynyloxy, preferably
C.sub.2-C.sub.20-alkynyloxy, aryloxy, preferably
C.sub.6-C.sub.24-aryloxy, alkoxycarbonyl, preferably
C.sub.2-C.sub.20-alkoxycarbonyl, alkylamino, preferably
C.sub.1-C.sub.30-alkylamino, alkylthio, preferably
C.sub.1-C.sub.30-alkylthio, arylthio, preferably
C.sub.6-C.sub.24-arylthio, alkylsulphonyl, preferably
C.sub.1-C.sub.20-alkylsulphonyl, or alkylsulphinyl, preferably
C.sub.1-C.sub.20-alkylsulphinyl radical, each of which may
optionally be substituted by one or more alkyl, halogen, alkoxy,
aryl or heteroaryl radicals, X.sup.1 and X.sup.2 are identical or
different and are two ligands, preferably anionic ligands, and L
represents identical or different ligands, preferably uncharged
electron donors, are used as catalyst.
8. The Catalyst system according to claim 7, wherein X.sup.1 and
X.sup.2 are identical or different and are each hydrogen, halogen,
pseudohalogen, straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.6-C.sub.24-aryl, C.sub.1-C.sub.20-alkoxy,
C.sub.6-C.sub.24-aryloxy, C.sub.3-C.sub.20-alkyldiketonate,
C.sub.6-C.sub.24-aryldiketonate, C.sub.1-C.sub.20-carboxylate,
C.sub.1-C.sub.20-alkylsulphonate, C.sub.6-C.sub.24-arylsulphonate,
C.sub.1-C.sub.20-alkylthiol, C.sub.6-C.sub.24-arylthiol,
C.sub.1-C.sub.20-alkylsulphonyl or C.sub.1-C.sub.20-alkylsulphinyl
radicals.
9. The Catalyst system according to claim 8, wherein X.sup.1 and
X.sup.2 are identical or different and are each halogen, in
particular fluorine, chlorine, bromine or iodine, benzoate,
C.sub.1-C.sub.5-carboxylate, C.sub.1-C.sub.5-alkyl, phenoxy,
C.sub.1-C.sub.5-alkoxy, C.sub.1-C.sub.8-alkylthiol,
C.sub.6-C.sub.24-arylthiol, C.sub.6-C.sub.24-aryl or
C.sub.1-C.sub.5-alkylsulphonate.
10. The Catalyst system according to claim 8 or 9, wherein X.sup.1
and X.sup.2 are identical and are each halogen, in particular
chlorine, CF.sub.3COO, CH.sub.3COO, CFH.sub.2COO,
(CH.sub.3).sub.3CO, (CF.sub.3).sub.2(CH.sub.3)CO,
(CF.sub.3)(CH.sub.3).sub.2CO, PhO (phenoxy), MeO (methoxy), EtO
(ethoxy), tosylate (p-CH.sub.3--C.sub.6H.sub.4--SO.sub.3), mesylate
(2,4,6-trimethylphenyl) or CF.sub.3SO.sub.3
(trifluoromethanesulphonate).
11. The Catalyst system according to claims 7, 8. 9 or 10, wherein
the two ligands L are each, independently of one another, a
phosphine, sulphonated phosphine, phosphate, phosphinite,
phosphonite, arsine, stibine, ether, amine, amide, sulphoxide,
carboxyl, nitrosyl, pyridine, thioether or imidazolidine ("Im")
ligand.
12. The Catalyst system according to claim 11, wherein the
imidazolidine radical (Im) has a structure of the general formula
(IIa) or (IIb), ##STR32## where R.sup.8, R.sup.9, R.sup.10,
R.sup.11 are identical or different and are each hydrogen,
straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.3-C.sub.20-cycloalkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.20-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.20-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl, C.sub.1-C.sub.20-alkylsulphonate,
C.sub.6-C.sub.20-arylsulphonate or
C.sub.1-C.sub.20-alkylsulphinyl.
13. The Catalyst system according to one or more of claims 1, 2 and
5, wherein the catalyst has the structure (III) or (IV), where Cy
is in each case cyclohexyl. ##STR33##
14. The Catalyst system according to according to one or more of
claims 1, 2 and 5, wherein catalysts of the general formula (B),
##STR34## where M is ruthenium or osmium, Y is oxygen (O), sulphur
(S), an N--R.sup.1 radical or a P--R.sup.1 radical, X.sup.1 and
X.sup.2 are identical or different ligands, R.sup.1 is an alkyl,
cycloalkyl, alkenyl, alkynyl, aryl, alkoxy, alkenyloxy, alkynyloxy,
aryloxy, alkoxycarbonyl, alkylamino, alkylthio, arylthio,
alkylsulphonyl or alkylsulphynyl radical, each of which may
optionally be substituted by one or more alkyl, halogen, alkoxy,
aryl or heteroaryl radicals, R.sup.2, R.sup.3, R.sup.4 and R.sup.5
are identical or different and are each hydrogen, organic or
inorganic radicals, R.sup.6 is hydrogen or an alkyl, alkenyl,
alkynyl or aryl radical and L is a ligand which has the same
meanings as the ligand L in the formula (A) mentioned in claim 7,
are used.
15. The Catalyst according to claim 14, wherein L is a
P(R.sup.7).sub.3 radical, where the radicals R.sup.7 are each,
independently of one another, C.sub.1-C.sub.6-alkyl,
C.sub.3-C.sub.8-cycloalkyl or aryl or else a substituted or
unsubstituted imidazolidine radical ("Im") which preferably has the
structure of the general formula (IIa) or (IIb) mentioned in claim
12 and particularly preferably has one of the structures (Va-f),
where Mes is in each case a 2,4,6-trimethylphenyl radical.
##STR35##
16. The Catalyst system according to claim 14 or 15, wherein
X.sup.1 and X.sup.2 in the general formula (B) assumes the meanings
of X.sup.1 and X.sup.2 in any of claims 8-10.
17. The Catalyst system according to one or more of claims 14, 15
and 16, wherein catalysts of the general formula (B1), ##STR36##
where M, L, X.sup.1, X.sup.2, R.sup.1, R.sup.2, R.sup.3, R.sup.4
and R.sup.5 have the meanings given for the general formula (B) in
claim 14, are used.
18. The Catalyst system according to claim 17, wherein catalysts of
the general formula (B1) in which M is ruthenium, X.sup.1 and
X.sup.2 are both halogen, in particular chlorine, R.sup.1 is a
straight-chain or branched C.sub.1-C.sub.12-alkyl radical, R.sup.2,
R.sup.3, R.sup.4, R.sup.5 have the meanings given for the general
formula (B) in claim 14 and L has the meanings given for the
general formula (B) in claim 14, are used.
19. The Catalyst system according to claim 17, wherein catalysts of
the general formula (B1) in which M is ruthenium, X.sup.1 and
X.sup.2 are both chlorine, R.sup.1 is an isopropyl radical,
R.sup.2, R.sup.3, R.sup.4, R.sup.5 are all hydrogen and L is a
substituted or unsubstituted imidazolidine radical of the formula
(IIa) or (IIb), ##STR37## where R.sup.8, R.sup.9, R.sup.10,
R.sup.11 are identical or different and are each hydrogen,
straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.3-C.sub.20-cycloalkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.24-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.24-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl, C.sub.1-C.sub.20-alkylsulphonate,
C.sub.6-C.sub.24-arylsulphonate or C.sub.1-C.sub.20-alkylsulphinyl,
are used.
20. The Catalyst system according to claim 17, wherein a catalyst
of the following structures (VI), (VII), (VIII), (IX), (X), (XI),
(XII), (XIII) or (XVII), where Mes is in each case a
2,4,6-trimethylphenyl radical, is used as catalyst of the general
structural formula (B1). ##STR38## ##STR39##
21. The Catalyst system according to claim 14, wherein a catalyst
of the general formula (B2), ##STR40## where, M, L, X, X.sup.2,
R.sup.1 and R.sup.6 have the meanings given for the general formula
(B) in claim 14, the radicals R.sup.12 are identical or different
and have the meanings given for the radicals R.sup.2, R.sup.3,
R.sup.4 and R.sup.5 in the general formula (B) in claim 14, with
the exception of hydrogen, and n is 0, 1, 2 or 3. is used.
22. The Catalyst system according to claim 21, wherein the catalyst
of the structures (XIV) or (XV), where Mes is in each case a
2,4,6-trimethylphenyl radical, is used. ##STR41##
23. The Catalyst system according to claim 14, wherein a catalyst
of the general formula (B3), ##STR42## where D.sup.1, D.sup.2,
D.sup.3 and D.sup.4 each have a structure of the general formula
(XVI) below which is bound via the methylene group to the silicon
of the formula (B3), ##STR43## where M, L, X.sup.1, X.sup.2,
R.sup.1, R.sup.2, R.sup.3, R.sup.5 and R.sup.6 have the meanings
given for the general formula (B) in claim 14, is used.
24. The Catalyst system according to one or more of claims 1, 2 and
5, wherein a catalyst of the general formula (B4), ##STR44## where
the symbol represents a support, is used.
25. The Catalyst systems according to one or more of claims 1, 2
and 5, wherein a catalyst of the general formula (C), ##STR45##
where M is ruthenium or osmium, X.sup.1 and X.sup.2 are identical
or different and are anionic ligands, the radicals R' are identical
or different and are organic radicals, Im is a substituted or
unsubstituted imidazolidine radical and An is an anion, is
used.
26. The Catalyst systems according to one or more of claims 1, 2
and 5, wherein a catalyst of the general formula (D), ##STR46##
where M is ruthenium or osmium, R.sup.13 and R.sup.14 are each,
independently of one another, hydrogen, C.sub.1-C.sub.20-alkyl,
C.sub.2-C.sub.20-alkenyl, C.sub.2-C.sub.20-alkynyl,
C.sub.6-C.sub.24-aryl, C.sub.1-C.sub.20-carboxylate,
C.sub.1-C.sub.20-alkoxy, C.sub.2-C.sub.20-alkenyloxy,
C.sub.2-C.sub.20-alkynyloxy, C.sub.6-C.sub.24-aryloxy,
C.sub.2-C.sub.20-alkoxycarbonyl, C.sub.1-C.sub.20-alkylthio,
C.sub.1-C.sub.20-alkylsulphonyl or C.sub.1-C.sub.20-alkylsulphinyl,
X.sup.3 is an anionic ligand, L.sup.2 is an uncharged n-bonded
ligand, regardless of whether it is monocyclic or polycyclic,
L.sup.3 is a ligand from the group of phosphines, sulphonated
phosphines, fluorinated phosphines, functionalized phosphines
having up to three aminoalkyl, ammonioalkyl, alkoxyalkyl,
alkoxycarbonylalkyl, hydrocarbonylalkyl, hydroxyalkyl or ketoalkyl
groups, phosphites, phosphinites, phosphonites, phosphine amines,
arsines, stibines, ethers, amines, amides, imines, sulphoxides,
thioethers and pyridines, Y.sup.- is a noncoordinating anion and n
is 0, 1, 2, 3, 4 or 5. is used.
27. The Catalyst systems according to one or more of claims 1, 2
and 5, wherein a catalyst of the general formula (E), ##STR47##
where M.sup.2 is molybdenum or tungsten, R.sup.15 and R.sup.16 are
identical or different and are each hydrogen,
C.sub.1-C.sub.20-alkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.24-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.1-C.sub.20-alkylsulphonyl or
C.sub.1-C.sub.20-alkylsulphinyl, R.sup.17 and R.sup.18 are
identical or different and are each a substituted or
halogen-substituted C.sub.1-C.sub.20-alkyl, C.sub.6-C.sub.24-aryl,
C.sub.6-C.sub.30-aralkyl radical or a silicone-containing analogue
thereof, is used.
28. The Catalyst systems according to one or more of claims 1, 2
and 5, wherein a catalyst of the general formula (F), ##STR48##
where M is ruthenium or osmium, X.sup.1 and X.sup.2 are identical
or different and are anionic ligands which can assume all the
meanings of X.sup.1 and X.sup.2 in the general formulae (A) and
(B), L are identical or different ligands which can assume all the
meanings of L in the general formulae (A) and (B), R.sup.19 and
R.sup.20 are identical or different and are each hydrogen or
substituted or unsubstituted alkyl, is used.
29. The Catalyst system according to one or more of claims 1, 2 and
5, wherein the metathesis catalyst and the salt or salts of the
general formula (I) is/are used in a weight ratio of
salt(s):metathesis catalyst of from 0.01:1 to 10000:1.
30. A process for reacting a chemical compound comprising
subjecting said chemical compound to a metathesis reaction in the
presence of the catalyst system according to one or more of claims
1, 2 and 5.
31. The process according to claim 30, wherein the metatheses
reaction is a ring-closing metatheses (RCM), a cross-metatheses
(CM) or a ring-opening metatheses (ROMP).
32. The process according to claim 30, wherein the chemical
compound is a nitrile rubber.
33. The process according to claim 30, wherein the salt or salts of
the general formula (I) is/are added in a solvent or without
solvent to the catalyst or a solution of the catalyst.
34. The process according to claim 30, wherein the amount of the
catalyst of the catalyst system is from 1 to 1000 ppm of noble
metal.
35. A process of preparing the catalyst system according to claim 1
by using a salt of the general formula (I) as constituent of the
catalyst system.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to novel catalyst systems and
a method for reacting chemical compounds by subjecting such
compounds to a metathesis reaction in the presence of said catalyst
systems.
BACKGROUND OF THE INVENTION
[0002] Metathesis reactions are widely used for chemical syntheses,
e.g. in the form of ring-closing metatheses (RCM), cross-metatheses
(CM) or ring-opening metatheses (ROMP). Metathesis reactions are
employed, for example, for the synthesis of olefins, for the
depolymerization of unsaturated polymers and for the synthesis of
telechelic polymers.
[0003] Metathesis catalysts are known, inter alia, from
WO-A-96/04289 and WO-A-97/06185. They have the following
in-principle structure: ##STR1## where M is osmium or ruthenium,
the radicals R are identical or different organic radicals having a
wide range of structural variation, X.sup.1 and X.sup.2 are anionic
ligands and L are uncharged electron donors. The customary term
"anionic ligands" is used in the literature regarding such
metathesis catalysts to describe ligands which are always
negatively charged with a closed electron shell when regarded
separately from the metal centre.
[0004] Metathesis reactions have recently also become increasingly
important for the degradation of nitrile rubbers.
[0005] Nitrile rubber, also referred to as "NBR" for short, is
rubber which is a copolymer or terpolymer of at least one
.alpha.,.beta.-unsaturated nitrile, at least one conjugated diene
and, if appropriate, one or more further copolymerizable
monomers.
[0006] Hydrogenated nitrile rubber, also referred to as "HNBR" for
short, is produced by hydrogenation of nitrile rubber. Accordingly,
the C.dbd.C double bonds of the copolymerized diene units have been
completely or partly hydrogenated in HNBR. The degree of
hydrogenation of the copolymerized diene units is usually in the
range from 50 to 100%.
[0007] Hydrogenated nitrile rubber is a specialty rubber which has
very good heat resistance, an excellent resistance to ozone and
chemicals and also an excellent oil resistance.
[0008] The abovementioned physical and chemical properties of HNBR
are associated with very good mechanical properties, in particular
a high abrasion resistance. For this reason, HNBR has found wide
use in a variety of applications. HNBR is used, for example, for
seals, hoses, belts and damping elements in the automobile sector,
also for stators, oil well seals and valve seals in the field of
oil extraction and also for numerous parts in the aircraft
industry, the electronics industry, mechanical engineering and
shipbuilding.
[0009] Commercially available HNBR grades usually have a Mooney
viscosity (ML 1+4 at 100.degree. C.) in the range from 55 to 105,
which corresponds to a weight average molecular weight M.sub.w
(method of determination: gel permeation chromatography (GPC)
against polystyrene equivalents) in the range from about 200 000 to
500 000. The polydispersity index PDI (PDI=M.sub.w/M.sub.n, where
M.sub.w is the weight average molecular weight and M.sub.n is the
number average molecular weight), which gives information about the
width of the molecular weight distribution, measured here is
frequently 3 or above. The residual double bond content is usually
in the range from 1 to 18% (determined by IR spectroscopy).
[0010] The processability of HNBR is subject to severe restrictions
as a result of the relatively high Mooney viscosity. For many
applications, it would be desirable to have an HNBR grade which has
a lower molecular weight and thus a lower Mooney viscosity. This
would decisively improve the processability.
[0011] Numerous attempts have been made in the past to shorten the
chain length of HNBR by degradation. For example, the molecular
weight can be decreased by thermomechanical treatment
(mastication), e.g. on a roll mill or in a screw apparatus (EP-A-0
419 952). However, this thermomechanical degradation has the
disadvantage that functional groups such as hydroxyl, keto,
carboxyl and ester groups, are incorporated into the molecule as a
result of partial oxidation and, in addition, the microstructure of
the polymer is substantially altered.
[0012] The preparation of HNBR having low molar masses
corresponding to a Mooney viscosity (ML 1+4 at 100.degree. C.) in
the range below 55 or a number average molecular weight of about
M.sub.n<200 000 g/mol was for a long time not possible by means
of established production processes since, firstly, a step increase
in the Mooney viscosity occurs in the hydrogenation of NBR and,
secondly, the molar mass of the NBR feedstock used for the
hydrogenation cannot be reduced at will since otherwise the work-up
can no longer be carried out in the industrial plants available
because the product is too sticky. The lowest Mooney viscosity of
an NBR feedstock which can be processed without difficulties in an
established industrial plant is about 30 Mooney units (ML 1+4 at
100.degree. C.). The Mooney viscosity of the hydrogenated nitrile
rubber obtained using such an NBR feedstock is in the order of 55
Mooney units (ML 1+4 at 100.degree. C.). The Mooney viscosity is
determined in accordance with ASTM standard D 1646.
[0013] In the more recent prior art, this problem is solved by
reducing the molecular weight of the nitrile rubber prior to
hydrogenation by degradation to a Mooney viscosity (ML 1+4 at
100.degree. C.) of less than 30 Mooney units or a number average
molecular weight of M.sub.n<70 000 g/mol. The decrease in the
molecular weight is achieved by metathesis in which low molecular
weight 1-olefins are usually added. The metathesis of nitrile
rubber is described, for example, in WO-A-02/100905, WO-A-02/100941
and WO-A-03/002613. The metathesis reaction is advantageously
carried out in the same solvent as the hydrogenation reaction (in
situ) so that the degraded nitrile rubber does not have to be
isolated from the solvent after the degradation reaction is
complete before it is subjected to the subsequent hydrogenation.
Metathesis catalysts which have a tolerance towards polar groups,
in particular towards nitrile groups, are used for catalyzing the
metathetic degradation reaction.
[0014] WO-A-02/100905 and WO-A-02/100941 describe a process which
comprises degradation of nitrile rubber starting polymers by olefin
metathesis and subsequent hydrogenation to form HNBR having a low
Mooney viscosity. Here, a nitrile rubber is reacted in a first step
in the presence of a coolefin and specific catalysts based on
osmium, ruthenium, molybdenum or tungsten complexes and
hydrogenated in a second step. Hydrogenated nitrile rubbers having
a weight average molecular weight (M.sub.w) in the range from 30
000 to 250 000, a Mooney viscosity (ML 1+4 at 100.degree. C.) in
the range from 3 to 50 and a polydispersity index PDI of less than
2.5 can be obtained by this route.
[0015] The metathesis of nitrile rubber can be carried out using,
for example, the catalyst
bis(tricyclohexylphosphine)benzylideneruthenium dichloride shown
below. ##STR2##
[0016] After metathesis and hydrogenation, the nitrile rubbers have
a lower molecular weight and also a narrower molecular weight
distribution than the hydrogenated nitrile rubbers which have
hitherto been able to be prepared according to the prior art.
[0017] However, the amounts of Grubbs (I) catalyst employed for
carrying out the metathesis are large. In the experiments in
WO-A-03/002613, they are, for example, 307 ppm and 61 ppm of Ru
based on the nitrile rubber used. The reaction times necessary are
also long and the molecular weights after the degradation are still
relatively high (see Example 3 of WO-A-03/002613, in which
M.sub.w=180 000 g/mol and M.sub.n=71 000 g/mol).
[0018] US 2004/0127647 A1 describes blends based on low molecular
weight HNBR rubbers having a bimodal or multimodal molecular weight
distribution and also vulcanizates of these rubbers. To carry out
the metathesis, 0.5 phr of Grubbs I catalyst is used according to
the examples. This corresponds to the large amount of 614 ppm of
ruthenium based on the nitrile rubber used.
[0019] Furthermore, WO-A-00/71554 discloses a group of catalysts
which are known in the technical field as "Grubbs (II)
catalysts".
[0020] If such a "Grubbs(II) catalyst", e.g. the catalyst
1,3-bis(2,4,6-trimethylphenyl)-2-imidazolidenylidene)(tricyclohexylphosph-
ine)ruthenium(phenylmethylene) dichloride, is used for the
metathesis of NBR (US-A-2004/0132891), this can be carried out
successively even without the use of a coolefin. ##STR3##
[0021] After the subsequent hydrogenation, which is preferably
carried out in situ, the hydrogenated nitrile rubber has lower
molecular weights and a narrower molecular weight distribution
(PDI) than when using catalysts of the Grubbs (I) type. In terms of
the molecular weight and the molecular weight distribution, the
metathetic degradation thus proceeds more efficiently when using
catalysts of the Grubbs II type than when using catalysts of the
Grubbs I type. However, the amounts of ruthenium necessary for this
efficient metathetic degradation are still relatively high. Long
reaction times are also still required for carrying out the
metathesis using the Grubbs II catalyst.
[0022] In all the abovementioned processes for the metathetic
degradation of nitrile rubber, relatively large amounts of catalyst
have to be used and long reaction times are required in order to
produce the desired low molecular weight nitrile rubbers by means
of metathesis.
[0023] The activity of the catalysts used is also of critical
importance in other types of metathesis reactions.
[0024] In J. Am. Chem. Soc. 1997, 119, 3887-3897, it is stated that
in the ring-closing metathesis of diethyl diallylmalonate, ##STR4##
the activity of the catalysts of the Grubbs I type can be increased
by additions of CuCl and CuCl.sub.2. This increase in activity is
explained by a shift in the dissociation equilibrium resulting from
a phosphane ligand which is eliminated reacting with copper ions to
form copper-phosphane complexes.
[0025] However, this increase in activity due to copper salts in
the abovementioned ring-closing metathesis cannot be carried over
to any desired other types of metathesis reactions. Our studies
have unexpectedly shown that although the addition of copper salts
leads to an initial acceleration of the metathesis reaction in the
metathetic degradation of nitrile rubbers, a significant decrease
in the efficiency of the metathesis is observed: the molecular
weights which can ultimately be achieved for the degraded nitrile
rubbers are substantially higher than when the metathesis reaction
is carried out in the presence of the same catalyst but in the
absence of the copper salts.
SUMMARY OF THE INVENTION
[0026] It was therefore an object of the invention to find
universally usable catalyst systems which in each case have an
increased activity when employed in the various types of metathesis
reactions, in order thereby to reduce the amounts of catalyst
necessary, in particular the amounts of noble metal present
therein. For the metathetic degradation of nitrile rubber in
particular, possible ways of making an increase in activity of the
catalyst used possible without gelling of the nitrile rubber are to
be found.
[0027] It has surprisingly been found that the activity of
metathesis catalysts can be increased when they are used in
combination with salts other than copper salts.
DETAILED DESCRIPTION OF THE INVENTION
[0028] The invention therefore provides a catalyst system
comprising a metathesis catalyst and one or more salts of the
general formula (I) K.sup.n+A.sup.z- (I) where K is a cation with
the exception of copper and A is an anion, where n is 1, 2 or 3 and
z is 1, 2 or 3.
[0029] For the purposes of the present patent application and
invention, all the definitions of radicals, parameters or
explanations given above or below in general terms or in preferred
ranges can be combined with one another in any way, i.e. including
combinations of the respective ranges and preferred ranges.
[0030] The term "substituted" used for the purposes of the present
patent application in respect of the metathesis catalyst or the
salt of the general formula (I) means that a hydrogen atom on an
indicated radical or atom has been replaced by one of the groups
indicated in each case, with the proviso that the valence of the
atom indicated is not exceeded and the substitution leads to a
stable compound.
[0031] Suitable cations are based on elements from the Periodic
Table (main groups and transition elements) which can form cations
bearing one, two or three positive charges, with the exception of
copper.
[0032] Suitable cations are, for example, lithium, sodium,
potassium rubidium, caesium, francium, beryllium, magnesium,
calcium, strontium, barium, aluminium, gallium, indium, thallium,
germanium, tin, lead, arsenic, antimony, bismuth, scandium,
yttrium, titanium, zirconium, hafnium, vanadium, niobium, tantalum,
chromium, molybdenum, tungsten, manganese, technetium, rhenium,
iron, ruthenium, osmium, cobalt, rhodium, iridium, nickel,
palladium, platinum, silver, gold, zinc, cadmium, mercury and also
all elements of the group of the rare earths, in particular cerium,
praseodynium and neodymium, and the elements of the actinides.
[0033] Further suitable cations are complex cations based on
nitrogen, phosphorus or sulphur. It is possible to use, for
example, tetralkylammonium, tetraarylammonium, hydroxylammonium,
tetraalkylphosphonium, tetraarylphosphonium, sulphonium, anilinium,
pyridinium, imidazolium, guanidinium and hydrazinium cations and
also cationic ethylenediamine derivatives.
[0034] The alkyl radicals in all the abovementioned complex cations
can be identical or different and are usually each a straight-chain
or branched C.sub.1-C.sub.30-alkyl radical, preferably a
C.sub.1-C.sub.20-alkyl radical, particularly preferably a
C.sub.1-C.sub.18-alkyl radical. These alkyl radicals can also be
substituted by aryl radicals. C.sub.1-C.sub.18-Alkyl encompasses,
for example, methyl, ethyl, n-propyl, isopropyl, n-butyl,
sec-butyl, tert-butyl, n-pentyl, 1-methylbutyl, 2-methylbutyl,
3-methylbutyl, neopentyl, 1-ethylpropyl, cyclohexyl, cyclopentyl,
n-hexyl, 1,1-dimethylpropyl, 1,2-dimethylpropyl,
1,2-dimethylpropyl, 1-methylpentyl, 2-methylpentyl, 3-methylpentyl,
4-methylpentyl, 1,1-dimethylbutyl, 1,2-dimethylbutyl,
1,3-dimethylbutyl, 2,2-dimethylbutyl, 2,3-dimethylbutyl,
3,3-dimethylbutyl, 1-ethylbutyl, 2-ethylbutyl,
1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl,
1-ethyl-1-methylpropyl, 1-ethyl-2-methylpropyl, n-heptyl, n-octyl,
n-nonyl, n-decyl, n-undexyl, n-dodecyl, n-tridecyl, n-tetradecyl,
n-hexadecyl, n-octadecyl and benzyl.
[0035] The aryl radicals in all the abovementioned complex cations
can likewise be identical or different and are usually each a
C.sub.6-C.sub.24-aryl radical, preferably a C.sub.6-C.sub.14-aryl
radical, particularly preferably a C.sub.6-C.sub.10-aryl radical.
Examples of C.sub.6-C.sub.24-aryl are phenyl, o-, p-, m-tolyl,
naphthyl, phenanthrenyl, anthracenyl and fluorenyl.
[0036] The sulphonium cations of the [R.sub.3S].sup.+ type bear
three identical or different radicals which can be aliphatic or
aromatic in nature. These radicals can be alkyl or aryl radicals
having the abovementioned general, preferred and particularly
preferred meanings.
[0037] Particularly preferred complex cations are
benzyldodecyldimethylammonium, didecyldimethylammonium,
dimethylanilinium,
N-alkyl-N,N-bis-(2-hydroxyalkyl)-N-benzylammonium,
N,N,N-triethylbenzolmethanaminium, O-methyluronium,
S-methylthiuronium, pyridinium, tetrabutylammonium,
tetramethyluronium, tetracetylammonium, tetrabutylphosphonium,
tetraphenylphosphonium, diphenylguanidinium, di-o-tolylguanidinium,
butyldiphenylsulphonium, tributylsulphonium.
[0038] In the general formula (I), A is a singly, doubly, or triply
charged anion, preferably from the group consisting of halides,
pseudohalides, complex anions, anions of organic acids, aliphatic
or aromatic sulphonates, aliphatic or aromatic sulphates,
phosphonates, phosphates, thiophosphates, xanthogenates,
dithiocarbamates and noncoordinating anions.
[0039] Preferred halides are fluoride, chloride, bromide,
iodide.
[0040] Preferred pseudohalides are, for example triiodide, azide,
cyamide, thiocyamide, thiocyanate and interhalides.
[0041] Suitable complex anions are, for example, sulphite,
sulphate, dithionite, thiosulphate, carbonate, hydrogencarbonate,
perthiocarbonate, nitrite, nitrate, perchlorate, tetrafluoroborate,
tetrafluoroaluminate, hexafluorophosphate, hexafluoroarsenate,
hexafluoroantimonate and hexachloroantimonate.
[0042] Preferred singly, doubly or triply charged anions of organic
acids are singly, doubly or triply charged anions of organic
carboxylic acids having from 1 to 20 carbon atoms. The organic
carboxylic acids can be saturated or monounsaturated or
polyunsaturated. Selected examples are formate, acetate,
propionate, butyrate, oleate, palmitate, stearate, versatate,
acrylate, methacrylate, crotonate, benzoate, naphthalenecarbonate,
oxalate, salicylate, terephthalate, fumarate, maleate, itaconate
and abietate.
[0043] Suitable aliphatic or aromatic sulphonates are
anthraquinone-2-sulphonate, benzenesulphonate,
benzene-1,3-disulphonate, decane-1-sulphonate,
hexadecane-1-sulphonate, hydroquinonemono-sulphonate,
methyl-4-toluenesulphonate, naphthalene-1-sulphonate,
naphthalene-1,5-disulphonate, tosylate and mesylate.
[0044] Suitable aliphatic or aromatic sulphates are, for example,
dodecylsulphate and alkylbenzenesulphates.
[0045] Suitable phosphonates, phosphates and thiophosphates are
vinylphosphonate, ethylphosphonate, butylphosphonate,
cetylphosphonate, dibutylphosphate, dioctylphosphate,
dibutyldithiophosphate and dioctylthiophosphate.
[0046] Suitable aliphatic or aromatic xanthogenates are
ethylxanthogenate, butylxanthogenate, phenylxanthogenate,
benzylxanthogenate, etc.
[0047] Suitable aliphatic or aromatic dithiocarbamates are
dimethyldithiocarbamate, diethyldithiocarbamate,
dibutyldithiocarbamate and dibenzyldithiocarbamate.
[0048] Noncoordinating anions are, for example,
tetrakis[pentafluorophenyl]borate,
pentakis-[pentafluorophenyl]phosphate,
tetrakis[3,5-trifluoromethylphenyl]borate,
pentakis[3,5-trifluoro-methylphenyl]phosphate and
pentakis[pentafluorophenyl]cyclohexadienyl anion.
[0049] For the purposes of the following definitions, all general
or preferred or particularly preferred definitions of radicals,
parameters or explanations mentioned for a particular catalyst type
can be combined with one another in any way, i.e. including
combinations of the respective ranges and preferred ranges of the
catalyst types.
[0050] Suitable catalysts in the catalyst systems of the invention
are compounds of the general formula (A) ##STR5## where [0051] M is
osmium or ruthenium, [0052] the radicals R are identical or
different and are each an alkyl, preferably C.sub.1-C.sub.30-alkyl,
cycloalkyl, preferably C.sub.3-C.sub.20-cycloalkyl, alkenyl,
preferably C.sub.2-C.sub.20-alkenyl, alkynyl, preferably
C.sub.2-C.sub.20-alkynyl, aryl, preferably C.sub.6-C.sub.24-aryl,
carboxylate, preferably C.sub.1-C.sub.20-carboxylate, alkoxy,
preferably C.sub.1-C.sub.20-alkoxy, alkenyloxy, preferably
C.sub.2-C.sub.20-alkenyloxy, alkynyloxy, preferably
C.sub.2-C.sub.20-alkynyloxy, aryloxy, preferably
C.sub.6-C.sub.24-aryloxy, alkoxycarbonyl, preferably
C.sub.2-C.sub.20-alkoxycarbonyl, alkylamino, preferably
C.sub.1-C.sub.30-alkylamino, alkylthio, preferably
C.sub.1-C.sub.30-alkylthio, arylthio, preferably
C.sub.6-C.sub.24-arylthio, alkylsulphonyl, preferably
C.sub.1-C.sub.20-alkylsulphonyl, or alkylsulphinyl, preferably
C.sub.1-C.sub.20-alkylsulphinyl radical, each of which may
optionally be substituted by one or more alkyl, halogen, alkoxy,
aryl or heteroaryl radicals, [0053] X.sup.1 and X.sup.2 are
identical or different and are two ligands, preferably anionic
ligands, and [0054] L represents identical or different ligands,
preferably uncharged electron donors.
[0055] In the catalysts of the general formula (A), X.sup.1 and
X.sup.2 are identical or different and are two ligands, preferably
anionic ligands.
[0056] X.sup.1 and X.sup.2 can be, for example, hydrogen, halogen,
pseudohalogen, straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.6-C.sub.24-aryl, C.sub.1-C.sub.20-alkoxy,
C.sub.6-C.sub.24-aryloxy, C.sub.3-C.sub.20-alkyldiketonate,
C.sub.6-C.sub.24-aryldiketonate, C.sub.1-C.sub.20-carboxylate,
C.sub.1-C.sub.20-alkylsulphonate, C.sub.6-C.sub.24-arylsulphonate,
C.sub.1-C.sub.20-alkylthiol, C.sub.6-C.sub.24-arylthiol,
C.sub.1-C.sub.20-alkylsulphonyl or C.sub.1-C.sub.20-alkylsulphinyl
radicals.
[0057] The abovementioned radicals X.sup.1 and X.sup.2 can also be
substituted by one or more further radicals, for example by
halogen, preferably fluorine, C.sub.1-C.sub.10-alkyl,
C.sub.1-C.sub.10-alkoxy or C.sub.6-C.sub.24-aryl, where these
radicals may also in turn be substituted by one or more
substitutents selected from the group consisting of halogen,
preferably fluorine, C.sub.1-C.sub.5-alkyl, C.sub.1-C.sub.5-alkoxy
and phenyl.
[0058] In a preferred embodiment, X.sup.1 and X.sup.2 are identical
or different and are each halogen, in particular fluorine,
chlorine, bromine or iodine, benzoate, C.sub.1-C.sub.5-carboxylate,
C.sub.1-C.sub.5-alkyl, phenoxy, C.sub.1-C.sub.5-alkoxy,
C.sub.1-C.sub.5-alkylthiol, C.sub.6-C.sub.24-arylthiol,
C.sub.6-C.sub.24-aryl or C.sub.1-C.sub.5-alkylsulphonate.
[0059] In a particularly preferred embodiment, X.sup.1 and X.sup.2
are identical and are each halogen, in particular chlorine,
CF.sub.3COO, CH.sub.3COO, CFH.sub.2COO, (CH.sub.3).sub.3CO,
(CF.sub.3).sub.2(CH.sub.3)CO, (CF.sub.3)(CH.sub.3).sub.2CO, PhO
(phenoxy), MeO (methoxy), EtO (ethoxy), tosylate
(p-CH.sub.3--C.sub.6H.sub.4--SO.sub.3), mesylate
(2,4,6-trimethylphenyl) or CF.sub.3SO.sub.3
(trifluoromethanesulphonate).
[0060] In the general formula (A), L represents identical or
different ligands, preferably uncharged electron donors.
[0061] The two ligands L can, for example, each be, independently
of one another, a phosphine, sulphonated phosphine, phosphate,
phosphinite, phosphonite, arsine, stibine, ether, amine, amide,
sulphoxide, carboxyl, nitrosyl, pyridine, thioether or
imidazolidine ("Im") ligand.
[0062] Preference is given to the two ligands L each being,
independently of one another, a C.sub.6-C.sub.24-arylphosphine,
C.sub.1-C.sub.5-alkylphosphine or
C.sub.3-C.sub.20-cycloalkylphosphine ligand, a sulphonated
C.sub.6-C.sub.24-arylphosphine or C.sub.1-C.sub.10-alkylphosphine
ligand, a C.sub.6-C.sub.24-aryl phosphinite or
C.sub.1-C.sub.10-alkyl phosphinite ligand, a C.sub.6-C.sub.24-aryl
phosphonite or C.sub.1-C.sub.10-alkyl phosphonite ligand, a
C.sub.6-C.sub.24-aryl phosphite or C.sub.1-C.sub.10-alkylphosphite
ligand, a C.sub.6-C.sub.24-arylarsine or
C.sub.1-C.sub.10-alkylarsine ligand, a C.sub.6-C.sub.24-arylamine
or C.sub.1-C.sub.10-alkylamine ligand, a pyridine ligand, a
C.sub.6-C.sub.24-aryl sulphoxide or C.sub.1-C.sub.10-alkyl
sulphoxide ligand, a C.sub.6-C.sub.24-aryl ether or
C.sub.1-C.sub.10-alkyl ether ligand or a C.sub.6-C.sub.24-arylamide
or C.sub.1-C.sub.10-alkylamide ligand, each of which may be
substituted by a phenyl group which may in turn be substituted by a
halogen, C.sub.1-C.sub.5 alkyl radical or C.sub.1-C.sub.5-alkoxy
radical.
[0063] The term phosphine includes, for example, PPh.sub.3,
P(p-Tol).sub.3, P(o-Tol).sub.3, PPh(CH.sub.3).sub.2,
P(CF.sub.3).sub.3, P(p-FC.sub.6H.sub.4).sub.3,
P(p-CF.sub.3C.sub.6H.sub.4).sub.3,
P(C.sub.6H.sub.4--SO.sub.3Na).sub.3,
P(CH.sub.2C.sub.6H.sub.4--SO.sub.3Na).sub.3, P(iso-Pr).sub.3,
P(CHCH.sub.3(CH.sub.2CH.sub.3)).sub.3, P(cyclopentyl).sub.3,
P(cyclohexyl).sub.3, P(neopentyl).sub.3 and P(neophenyl).sub.3.
[0064] Phosphinite includes, for example, triphenyl phosphinite,
tricyclohexyl phosphinite, triisopropyl phosphinite and methyl
diphenylphosphinite.
[0065] Phosphite includes, for example, triphenyl phosphite,
tricyclohexyl phosphite, tri-tert-butyl phosphite, triisopropyl
phosphite and methyl diphenyl phosphate.
[0066] Stibine includes, for example, triphenylstibine,
tricyclohexylstibine and trimethylstibene.
[0067] Sulphonate includes, for example,
trifluoromethanesulphonate, tosylate and mesylate.
[0068] Sulphoxide includes, for example, CH.sub.3S(.dbd.O)CH.sub.3
and (C.sub.6H.sub.5).sub.2SO.
[0069] Thioether includes, for example, CH.sub.3SCH.sub.3,
C.sub.6H.sub.5SCH.sub.3, CH.sub.3OCH.sub.2CH.sub.2SCH.sub.3 and
tetrahydrothiophene.
[0070] The imidazolidine radical (Im) usually has a structure of
the general formula (IIa) or (IIb), ##STR6## where [0071] R.sup.8,
R.sup.9, R.sup.10, R.sup.11 are identical or different and are each
hydrogen, straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.3-C.sub.20-cycloalkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.20-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.20-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl, C.sub.1-C.sub.20-alkylsulphonate,
C.sub.6-C.sub.20-arylsulphonate or
C.sub.1-C.sub.20-alkylsulphinyl.
[0072] If desired, one or more of the radicals R.sup.8, R.sup.9,
R.sup.10, R.sup.11 can, independently of one another, be
substituted by one or more substitutents, preferably straight-chain
or branched C.sub.1-C.sub.10-alkyl, C.sub.3-C.sub.8-cycloalkyl,
C.sub.1-C.sub.10-alkoxy or C.sub.6-C.sub.24-aryl, with these
abovementioned substitutents in turn being able to be substituted
by one or more radicals, preferably selected from the group
consisting of halogen, in particular chlorine or bromine,
C.sub.1-C.sub.5-alkyl, C.sub.1-C.sub.5-alkoxy and phenyl.
[0073] In a preferred embodiment of the novel catalysts of the
general formula (A), R.sup.8 and R.sup.9 are each, independently of
one another, hydrogen, C.sub.6-C.sub.24-aryl, particularly
preferably phenyl, straight-chain or branched
C.sub.1-C.sub.10-alkyl, particularly preferably propyl or butyl, or
together form, with inclusion of the carbon atoms to which they are
bound, a cycloalkyl or aryl radical, where all the abovementioned
radicals may in turn be substituted by one or more further radicals
selected from the group consisting of straight-chain or branched
C.sub.1-C.sub.10-alkyl, C.sub.1-C.sub.10-alkoxy,
C.sub.6-C.sub.24-aryl and functional groups selected from the group
consisting of hydroxy, thiol, thioether, ketone, aldehyde, ester,
ether, amine, imine, amide, nitro, carboxyl, disulphide, carbonate,
isocyanate, carbodiimide, carboalkoxy, carbamate and halogen.
[0074] In a preferred embodiment of the novel catalysts of the
general formula (B), the radicals R.sup.10 and R.sup.11 are
identical or different and are each straight-chain or branched
C.sub.1-C.sub.10-alkyl, particularly preferably i-propyl or
neopentyl, C.sub.3-C.sub.10-cycloalkyl, preferably adamantyl,
C.sub.6-C.sub.24-aryl, particularly preferably phenyl,
C.sub.1-C.sub.10-alkylsulphonate, particularly preferably
methanesulphonate, C.sub.6-C.sub.10-arylsulphonate, particularly
preferably p-toluenesulphonate.
[0075] Radicals R.sup.10 and R.sup.11 of the abovementioned type
may optionally be substituted by one or more further radicals
selected from the group consisting of straight-chain or branched
C.sub.1-C.sub.5-alkyl, in particular methyl,
C.sub.1-C.sub.5-alkoxy, aryl and functional groups selected from
the group consisting of hydroxy, thiol, thioether, ketone,
aldehyde, ester, ether, amine, imine, amide, nitro, carboxyl,
disulphide, carbonate, isocyanate, carbodiimide, carboalkoxy,
carbamate and halogen.
[0076] In particular, the radicals R.sup.10 and R.sup.11 may be
identical or different and are each i-propyl, neopentyl, adamantyl
or mesityl.
[0077] A variety of representatives of the catalysts of the formula
(A) are known in principle, e.g. from WO-A-96/04289 and
WO-A-97/06185.
[0078] Particular preference is given to both ligands L in the
general formula (A) being identical or different trialkylphosphine
ligands in which at least one of the alkyl groups is a secondary
alkyl group or a cycloalkyl group, preferably isopropyl, isobutyl,
sec-butyl, neopentyl, cyclopentyl or cyclohexyl.
[0079] Particular preference is given to one ligand L in the
general formula (A) being a trialkylphosphine ligand in which at
least one of the alkyl groups is a secondary alkyl group or a
cycloalkyl group, preferably isopropyl, isobutyl, sec-butyl,
neopentyl, cyclopentyl or cyclohexyl.
[0080] Two catalysts which are preferred for the catalyst system of
the invention and come under the general formula (A) have the
structures (III) (Grubbs (I) catalyst) and (IV) (Grubbs (II)
catalyst), where Cy is cyclohexyl. ##STR7##
[0081] Further suitable metathesis catalysts in the catalyst
systems of the invention are catalysts of the general formula (B),
##STR8## where [0082] M is ruthenium or osmium, [0083] Y is oxygen
(O), sulphur (S), an N--R.sup.1 radical or a P--R.sup.1 radical,
where R.sup.1 is as defined below, [0084] X.sup.1 and X.sup.2 are
identical or different ligands, [0085] R.sup.1 is an alkyl,
cycloalkyl, alkenyl, alkynyl, aryl, alkoxy, alkenyloxy, alkynyloxy,
aryloxy, alkoxycarbonyl, alkylamino, alkylthio, arylthio,
alkylsulphonyl or alkylsulphynyl radical, each of which may
optionally be substituted by one or more alkyl, halogen, alkoxy,
aryl or heteroaryl radicals, [0086] R.sup.2, R.sup.3, R.sup.4 and
R.sup.5 are identical or different and are each hydrogen, organic
or inorganic radicals, [0087] R.sup.6 is hydrogen or an alkyl,
alkenyl, alkynyl or aryl radical and [0088] L is a ligand which has
the same meanings given for the formula (A).
[0089] The catalysts of the general formula (B) are known in
principle. Representatives of this class of compounds are the
catalysts described by Hoveyda et al. in US 2002/0107138 A1 and
Angew Chem. Int. Ed. 2003, 42, 4592, and the catalysts described by
Grela in WO-A-2004/035596, Eur. J. Org. Chem 2003, 963-966 and
Angew. Chem. Int. Ed. 2002, 41, 4038 and in J. Org. Chem. 2004, 69,
6894-96 and Chem. Eur. J 2004, 10, 777-784. The catalysts are
commercially available or can be prepared as described in the
references cited.
[0090] In the catalysts of the general formula (B), L is a ligand
which usually has an electron donor function and can have the same
general, preferred and particularly preferred meanings as L in the
general formula (A).
[0091] Furthermore, L in the general formula (B) is preferably a
P(R.sup.7).sub.3 radical, where the radicals R.sup.7 are each,
independently of one another, C.sub.1-C.sub.6-alkyl,
C.sub.3-C.sub.8-cycloalkyl or aryl or else a substituted or
unsubstituted imidazolidine radical ("Im").
[0092] C.sub.1-C.sub.6-Alkyl is, for example, methyl, ethyl,
n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl,
1-methylbutyl, 2-methylbutyl, 3-methylbutyl, neopentyl,
1-ethylpropyl or n-hexyl.
[0093] C.sub.3-C.sub.8-Cycloalkyl encompasses cyclopropyl,
cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and
cyclooctyl.
[0094] Aryl encompasses an aromatic radical having from 6 to 24
skeletal carbon atoms. Preferred monocyclic, bicyclic or tricyclic
carbocyclic aromatic radicals having from 6 to 10 skeletal carbon
atoms are, for example, phenyl, biphenyl, naphthyl, phenanthrenyl
and anthracenyl.
[0095] The imidazolidine radical (Im) usually has a structure of
the general formula (IIa) or (IIb), ##STR9## where [0096] R.sup.8,
R.sup.9, R.sup.10, R.sup.11 are identical or different and are each
hydrogen, straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.3-C.sub.20-cycloalkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.20-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.20-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl, C.sub.1-C.sub.20-alkylsulphonate,
C.sub.6-C.sub.20-arylsulphonate or
C.sub.1-C.sub.20-alkylsulphinyl.
[0097] One or more of the radicals R.sup.8, R.sup.9, R.sup.10,
R.sup.11 may, independently of one another, optionally be
substituted by one or more substitutents, preferably straight-chain
or branched C.sub.1-C.sub.10-alkyl, C.sub.3-C.sub.8-cycloalkyl,
C.sub.1-C.sub.10-alkoxy or C.sub.6-C.sub.24-aryl, where these
abovementioned substitutents may in turn be substituted by one or
more radicals, preferably selected from the group consisting of
halogen, in particular chlorine or bromine, C.sub.1-C.sub.5-alkyl,
C.sub.1-C.sub.5-alkoxy and phenyl.
[0098] In a preferred embodiment of the novel catalysts of the
general formula (B), R.sup.8 and R.sup.9 are each, independently of
one another, hydrogen, C.sub.6-C.sub.24-aryl, particularly
preferably phenyl, straight-chain or branched
C.sub.1-C.sub.10-alkyl, particularly preferably propyl or butyl, or
together form, with inclusion of the carbon atoms to which they are
bound, a cycloalkyl or aryl radical, where all the abovementioned
radicals may in turn be substituted by one or more further radicals
selected from the group consisting of straight-chain or branched
C.sub.1-C.sub.10-alkyl, C.sub.1-C.sub.10-alkoxy,
C.sub.6-C.sub.24-aryl and functional groups selected from the group
consisting of hydroxy, thiol, thioether, ketone, aldehyde, ester,
ether, amine, imine, amide, nitro, carboxyl, disulphide, carbonate,
isocyanate, carbodiimide, carboalkoxy, carbamate and halogen.
[0099] In a preferred embodiment of the novel catalysts of the
general formula (B), the radicals R.sup.10 and R.sup.11 are
identical or different and are each straight-chain or branched
C.sub.1-C.sub.10-alkyl, particularly preferably i-propyl or
neopentyl, C.sub.3-C.sub.10-cycloalkyl, preferably adamantyl,
C.sub.6-C.sub.24-aryl, particularly preferably phenyl,
C.sub.1-C.sub.10-alkylsulphonate, particularly preferably
methanesulphonate, C.sub.6-C.sub.10-arylsulphonate, particularly
preferably p-toluenesulphonate.
[0100] Radicals R.sup.10 and R.sup.11 of the abovementioned type
may optionally be substituted by one or more further radicals
selected from the group consisting of straight-chain or branched
C.sub.1-C.sub.5-alkyl, in particular methyl,
C.sub.1-C.sub.5-alkoxy, aryl and functional groups selected from
the group consisting of hydroxy, thiol, thioether, ketone,
aldehyde, ester, ether, amine, imine, amide, nitro, carboxyl,
disulphide, carbonate, isocyanate, carbodiimide, carboalkoxy,
carbamate and halogen.
[0101] In particular, the radicals R.sup.10 and R.sup.11 may be
identical or different and are each i-propyl, neopentyl, adamantyl
or mesityl.
[0102] Particularly preferred imidazolidine radicals (Im) have the
following structures (Va-f), where Mes is in each case a
2,4,6-trimethylphenyl radical. ##STR10##
[0103] In the catalysts of the general formula (B), X.sup.1 and
X.sup.2 are identical or different and can be, for example,
hydrogen, halogen, pseudohalogen, straight-chain or branched
C.sub.1-C.sub.30-alkyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-alkoxy, C.sub.6-C.sub.24-aryloxy,
C.sub.3-C.sub.20-alkyldiketonate, C.sub.6-C.sub.24-aryldiketonate,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkylsulphonate,
C.sub.6-C.sub.24-arylsulphonate, C.sub.1-C.sub.20-alkylthiol,
C.sub.6-C.sub.24-arylthiol, C.sub.1-C.sub.20-alkylsulphonyl or
C.sub.1-C.sub.20-alkylsulphinyl.
[0104] The abovementioned radicals X.sup.1 and X.sup.2 can also be
substituted by one or more further radicals, for example by
halogen, preferably fluorine, C.sub.1-C.sub.10-alkyl,
C.sub.1-C.sub.10-alkoxy or C.sub.6-C.sub.24-aryl radicals, where
the latter radicals may also in turn be substituted by one or more
substitutents selected from the group consisting of halogen,
preferably fluorine, C.sub.1-C.sub.5-alkyl, C.sub.1-C.sub.8-alkoxy
and phenyl.
[0105] In a preferred embodiment, X.sup.1 and X.sup.2 are identical
or different and are each halogen, in particular fluorine,
chlorine, bromine or iodine, benzoate, C.sub.1-C.sub.5-carboxylate,
C.sub.1-C.sub.5-alkyl, phenoxy, C.sub.1-C.sub.5-alkoxy,
C.sub.1-C.sub.5-alkylthiol, C.sub.6-C.sub.24-arylthiol,
C.sub.6-C.sub.24-aryl or C.sub.1-C.sub.5-alkylsulphonate.
[0106] In a particularly preferred embodiment, X.sup.1 and X.sup.2
are identical and are each halogen, in particular chlorine,
CF.sub.3COO, CH.sub.3COO, CFH.sub.2COO, (CH.sub.3).sub.3CO,
(CF.sub.3).sub.2(CH.sub.3)CO, (CF.sub.3)(CH.sub.3).sub.2CO, PhO
(phenoxy), MeO (methoxy), EtO (ethoxy), tosylate
(p-CH.sub.3--C.sub.6H.sub.4--SO.sub.3), mesylate
(2,4,6-trimethylphenyl) or CF.sub.3SO.sub.3
(trifluoromethanesulphonate).
[0107] In the general formula (B), the radical R.sup.1 is an alkyl,
cycloalkyl, alkenyl, alkynyl, aryl, alkoxy, alkenyloxy, alkynyloxy,
aryloxy, alkoxycarbonyl, alkylamino, alkylthio, arylthio,
alkylsulphonyl or alkylsulphinyl radical, each of which may
optionally be substituted by one or more alkyl, halogen, alkoxy,
aryl or heteroaryl radicals.
[0108] The radical R.sup.1 is usually a C.sub.1-C.sub.30-alkyl,
C.sub.3-C.sub.20-cycloalkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-alkoxy, C.sub.2-C.sub.20-alkenyloxy,
C.sub.2-C.sub.20-alkynyloxy, C.sub.6-C.sub.24-aryloxy,
C.sub.2-C.sub.20-alkoxycarbonyl, C.sub.1-C.sub.20-alkylamino,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.24-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl or C.sub.1-C.sub.20-alkylsulphinyl
radical, each of which may optionally be substituted by one or more
alkyl, halogen, alkoxy, aryl or heteroaryl radicals.
[0109] R.sup.1 is preferably a C.sub.3-C.sub.20-cylcoalkyl radical,
a C.sub.6-C.sub.24-aryl radical or a straight-chain or branched
C.sub.1-C.sub.30-alkyl radical, with the latter optionally being
able to be interrupted by one or more double or triple bonds or one
or more heteroatoms, preferably oxygen or nitrogen. R.sup.1 is
particularly preferably a straight-chain or branched
C.sub.1-C.sub.12-alkyl radical.
[0110] The C.sub.3-C.sub.20-cycloalkyl radical encompasses, for
example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,
cycloheptyl and cyclooctyl.
[0111] The C.sub.1-C.sub.12-alkyl radical can be, for example,
methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl,
n-pentyl, 1-methylbutyl, 2-methylbutyl, 3-methylbutyl, neopentyl,
1-ethylpropyl, n-hexyl, n-heptyl, n-octyl, n-decyl or n-dodecyl. In
particular, R.sup.1 is methyl or isopropyl.
[0112] The C.sub.6-C.sub.24-aryl radical is an aromatic radical
having from 56 to 24 skeletal carbon atoms. As preferred
monocyclic, bicyclic or tricyclic carbocyclic aromatic radicals
having from 6 to 10 skeletal carbon atoms, mention may be made by
way of example of phenyl, biphenyl, naphthyl, phenanthrenyl or
anthracenyl.
[0113] In the general formula (B), the radicals R.sup.2, R.sup.3,
R.sup.4 and R.sup.5 are identical or different and can be hydrogen,
organic or inorganic radicals.
[0114] In a preferred embodiment, R.sup.2, R.sup.3, R.sup.4,
R.sup.5 are identical or different and are each hydrogen, halogen,
nitro, CF.sub.3 or an alkyl, cycloalkyl, alkenyl, alkynyl, aryl,
alkoxy, alkenyloxy, alkynyloxy, aryloxy, alkoxycarbonyl,
alkylamino, alkylthio, arylthio, alkylsulphonyl or alkylsulphinyl
radical, each of which may optionally be substituted by one or more
alkyl, alkoxy, halogen, aryl or heteroaryl radicals.
[0115] R.sup.2, R.sup.3, R.sup.4, R.sup.5 are usually identical or
different and are each hydrogen, halogen, preferably chlorine or
bromine, nitro, CF.sub.3 or a C.sub.1-C.sub.30-alkyl,
C.sub.3-C.sub.20-cylcoalkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-alkoxy, C.sub.2-C.sub.20-alkenyloxy,
C.sub.2-C.sub.20-alkynyloxy, C.sub.6-C.sub.24-aryloxy,
C.sub.2-C.sub.20-alkoxycarbonyl, C.sub.1-C.sub.20-alkylamino,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.24-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl or C.sub.1-C.sub.20-alkylsulphinyl
radical, each of which may optionally be substituted by one or more
C.sub.1-C.sub.30-alkyl, C.sub.1-C.sub.20-alkoxy, halogen,
C.sub.6-C.sub.24-aryl or heteroaryl radicals.
[0116] In a particularly useful embodiment, R.sup.2, R.sup.3,
R.sup.4, R.sup.5 are identical or different and are each nitro, a
straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.5-C.sub.20-cycloalkyl, straight-chain or branched
C.sub.1-C.sub.20-alkoxy radical or a C.sub.6-C.sub.24-aryl radical,
preferably phenyl or naphthyl. The C.sub.1-C.sub.30-alkyl radicals
and C.sub.1-C.sub.20-alkoxy radicals may optionally be interrupted
by one or more double or triple bonds or one or more heteroatoms,
preferably oxygen or nitrogen.
[0117] Furthermore, two or more of the radicals R.sup.2, R.sup.3,
R.sup.4 or R.sup.5 can also be bridged via aliphatic or aromatic
structures. For example, R.sup.3 and R.sup.4 can, with inclusion of
the carbon atoms to which they are bound in the phenyl ring of the
formula (B), form a fused-on phenyl ring so that overall a naphthyl
structure results.
[0118] In the general formula (B), R.sup.6 is hydrogen or an alkyl,
alkenyl, alkynyl or aryl radical. R.sup.6 is preferably hydrogen or
a C.sub.1-C.sub.30-alkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl or C.sub.6-C.sub.24-aryl radical. R.sup.6
is particularly preferably hydrogen.
[0119] Particularly suitable catalysts for the catalyst system of
the invention are catalysts of the general formula (B1) ##STR11##
where [0120] M, L, X.sup.1, X.sup.2, R.sup.1, R.sup.2, R.sup.3,
R.sup.4 and R.sup.5 can have the general, preferred and
particularly preferred meanings given for the general formula
(B).
[0121] These catalysts are known in principle, for example from US
2002/0107138 A1 (Hoveyda et al.), and can be obtained by
preparative methods indicated there.
[0122] Particular preference is given to catalysts of the general
formula (B1) in which
M is ruthenium,
X.sup.1 and X.sup.2 are both halogen, in particular, both
chlorine,
R.sup.1 is a straight-chain or branched C.sub.1-C.sub.12-alkyl
radical,
R.sup.2, R.sup.3, R.sup.4, R.sup.5 have the general and preferred
meanings given for the general formula (B) and
L has the general and preferred meanings given for the general
formula (B).
[0123] Very particular preference is given to catalysts of the
general formula (B1) in which
M is ruthenium,
X.sup.1 and X.sup.2 are both chlorine,
R.sup.1 is an isopropyl radical,
R.sup.2, R.sup.3, R.sup.4, R.sup.5 are all hydrogen and
[0124] L is a substituted or unsubstituted imidazolidine radical of
the formula (IIa) or (IIb), ##STR12## where [0125] R.sup.8,
R.sup.9, R.sup.10, R.sup.11 are identical or different and are each
hydrogen, straight-chain or branched C.sub.1-C.sub.30-alkyl,
C.sub.3-C.sub.20-cycloalkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.24-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.24-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl, C.sub.1-C.sub.20-alkylsulphonate,
C.sub.6-C.sub.24-arylsulphonate or
C.sub.1-C.sub.20-alkylsulphinyl.
[0126] As catalyst coming under the general structural formula (B1)
for the catalyst systems of the invention, especial preference is
given to those of the formula (VI), where Mes is in each case a
2,4,6-trimethylphenyl radical. ##STR13##
[0127] This catalyst is also referred to in the literature as
"Hoveyda catalyst".
[0128] Further suitable catalysts which come under the general
structural formula (B1) are those of the following formulae (VII),
(VIII), (IX), (X), (XI), (XII), (XIII) and (XVII), where Mes is in
each case a 2,4,6-trimethylphenyl radical. ##STR14## ##STR15##
[0129] Further suitable catalysts for the catalyst system of the
invention are catalysts of the general formula (B2) ##STR16## where
[0130] M, L, X.sup.1, X.sup.2, R.sup.1 and R.sup.6 have the general
and preferred meanings given for the formula (B), [0131] R.sup.12
are identical or different and have the general and preferred
meanings given for the radicals R.sup.2, R.sup.3, R.sup.4 and
R.sup.5 in the formula (B), with the exception of hydrogen, and
[0132] n is 0, 1, 2 or 3.
[0133] These catalysts are known in principle, for example from
WO-A-2004/035596 (Grela), and can be obtained by the preparative
methods indicated there.
[0134] Particular preference is given to catalysts of the general
formula (B2) in which
M is ruthenium,
X.sup.1 and X.sup.2 are both halogen, in particular both
chlorine,
R.sup.1 is a straight-chain or branched C.sub.1-C.sub.12-alkyl
radical,
R.sup.12 has the meanings given for the general formula (B),
n is 0, 1, 2 or 3,
R.sup.6 is hydrogen and
L has the meanings given for the general formula (B).
[0135] Very particular preference is given to catalysts of the
general formula (B2) in which
M is ruthenium,
X.sup.1 and X.sup.2 are both chlorine,
R.sup.1 is an isopropyl radical,
n is 0 and
[0136] L is a substituted or unsubstituted imidazolidine radical of
the formula (IIa) or (IIb), ##STR17## where [0137] R.sup.8,
R.sup.9, R.sup.10, R.sup.11 are identical or different and are each
hydrogen, straight-chain or branched, cyclic or acyclic
C.sub.1-C.sub.30-alkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.24-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.24-arylthio,
C.sub.1-C.sub.20-alkylsulphonyl, C.sub.1-C.sub.20-alkylsulphonate,
C.sub.6-C.sub.24-arylsulphonate or
C.sub.1-C.sub.20-alkylsulphinyl.
[0138] A particularly suitable catalyst which comes under the
general formula (B2) has the structure (XIV) ##STR18## and is also
referred to in the literature as "Grela catalyst".
[0139] A further suitable catalyst which comes under the general
formula (B2) has the structure (XV), where Mes is in each case a
2,4,6-trimethylphenyl radical. ##STR19##
[0140] In an alternative embodiment, it is also possible to use
dendritic catalysts of the general formula (B3), ##STR20## where
D.sup.1, D.sup.2, D.sup.3 and D.sup.4 each have a structure of the
general formula (XVI) below which is bound via the methylene group
to the silicon of the formula (B3), ##STR21## where [0141] M, L,
X.sup.1, X.sup.2, R.sup.1, R.sup.2, R.sup.3, R.sup.1 and R.sup.6
have the meanings given for the general formula (B) and can also
have the abovementioned preferred meanings.
[0142] Such catalysts of the general formula (B3) are known from US
2002/0107138 A1 and can be prepared according to the information
given there.
[0143] In a further alternative embodiment, it is possible to use a
catalyst of the formula (B4), ##STR22## where the symbol represents
a support.
[0144] The support is preferably a
poly(styrene-divinylbenzene)copolymer (PS-DVB).
[0145] These catalysts of the formula (B4) are known in principle
from Chem. Eur. J. 2004 10, 777-784 and can be obtained by the
preparative methods described there.
[0146] All the abovementioned catalysts of the type (B) can either
be used as such in the reaction mixture of the NBR metathesis or
can be applied to and immobilized on a solid support. As solid
phases or supports, it is possible to use materials which firstly
are inert towards the reaction mixture of the metathesis and
secondly do not impair the activity of the catalyst. It is possible
to use, for example, metals, glass, polymers, ceramic, organic
polymer spheres or inorganic sol-gels for immobilizing the
catalyst.
[0147] The catalyst system of the invention can also be prepared
using catalysts of the general formula (C), ##STR23## where M is
ruthenium or osmium, X.sup.1 and X.sup.2 can be identical or
different and are anionic ligands, the radicals R' are identical or
different and are organic radicals, Im is a substituted or
unsubstituted imidazolidine radical and An is an anion.
[0148] These catalysts are known in principle (cf., for example,
Angew. Chem. Int. Ed. 2004, 43, 6161-6165).
[0149] X.sup.1 and X.sup.2 in the general formula (C) can have the
same general, preferred and particularly preferred meanings as in
the formula (B).
[0150] The imidazolidine radical (Im) usually has a structure of
the general formula (IIa) or (IIb) which have already been
mentioned for the catalyst type of the formulae (A) and (B) and can
also have all the structures mentioned there as preferred, in
particular those of the formulae (Va)-(Vf).
[0151] The radicals R' in the general formula (C) are identical or
different and are each a straight-chain or branched
C.sub.1-C.sub.30-alkyl, C.sub.5-C.sub.30-cylcoalkyl or aryl
radical, with the C.sub.1-C.sub.30-alkyl radicals optionally being
able to be interrupted by one or more double or triple bonds or one
or more heteroatoms, preferably oxygen or nitrogen.
[0152] Aryl encompasses an aromatic radical having from 5 to 24
skeletal carbon atoms. As preferred monocyclic, bicyclic or
tricyclic carbocyclic aromatic radicals having from 6 to 10
skeletal carbon atoms, mention may be made by way of example of
phenyl, biphenyl, naphthyl, phenanthrenyl or anthracenyl.
[0153] The radicals R' in the general formula (C) are preferably
identical and are each phenyl, cyclohexyl, cyclopentyl, isopropyl,
o-tolyl, o-xylyl or mesityl.
[0154] Further suitable catalysts for the catalyst systems of the
invention are catalysts of the general formula (D), ##STR24## where
[0155] M is ruthenium or osmium, [0156] R.sup.13 and R.sup.14 are
each, independently of one another, hydrogen,
C.sub.1-C.sub.20-alkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.24-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.1-C.sub.20-alkylsulphonyl or
C.sub.1-C.sub.20-alkylsulphinyl, [0157] X.sup.3 is an anionic
ligand, [0158] L.sup.2 is an uncharged .pi.-bonded ligand,
regardless of whether it is monocyclic or polycyclic, [0159]
L.sup.3 is a ligand from the group of phosphines, sulphonated
phosphines, fluorinated phosphines, functionalized phosphines
having up to three aminoalkyl, ammonioalkyl, alkoxyalkyl,
alkoxycarbonylalkyl, hydrocarbonylalkyl, hydroxyalkyl or ketoalkyl
groups, phosphites, phosphinites, phosphonites, phosphine amines,
arsines, stibines, ethers, amines, amides, imines, sulphoxides,
thioethers and pyridines, [0160] Y.sup.- is a noncoordinating anion
and [0161] n is 0, 1, 2, 3, 4 or 5.
[0162] Further suitable catalysts for use in the catalyst systems
of the invention are catalysts of the general formula (E) ##STR25##
where [0163] M.sup.2 is molybdenum or tungsten, [0164] R.sup.15 and
R.sup.16 are identical or different and are each hydrogen,
C.sub.1-C.sub.20-alkyl, C.sub.2-C.sub.20-alkenyl,
C.sub.2-C.sub.20-alkynyl, C.sub.6-C.sub.24-aryl,
C.sub.1-C.sub.20-carboxylate, C.sub.1-C.sub.20-alkoxy,
C.sub.2-C.sub.20-alkenyloxy, C.sub.2-C.sub.20-alkynyloxy,
C.sub.6-C.sub.24-aryloxy, C.sub.2-C.sub.20-alkoxycarbonyl,
C.sub.1-C.sub.20-alkylthio, C.sub.1-C.sub.20-alkylsulphonyl or
C.sub.1-C.sub.20-alkylsulphinyl, [0165] R.sup.17 and R.sup.18 are
identical or different and are each a substituted or
halogen-substituted C.sub.1-C.sub.20-alkyl, C.sub.6-C.sub.24-aryl,
C.sub.6-C.sub.30-aralkyl radical or a silicone-containing analogue
thereof.
[0166] Further suitable catalysts for use in the catalyst systems
of the invention are catalysts of the general formula (F),
##STR26## where [0167] M is ruthenium or osmium, [0168] X.sup.1 and
X.sup.2 are identical or different and are anionic ligands which
can assume all the meanings of X.sup.1 and X.sup.2 in the general
formulae (A) and (B), [0169] L are identical or different ligands
which can assume all the general and preferred meanings of L in the
general formulae (A) and (B), [0170] R.sup.19 and R.sup.20 are
identical or different and are each hydrogen or substituted or
unsubstituted alkyl.
[0171] The catalyst systems of the invention thus comprise the
metathesis catalyst and one or more salts of the general formula
(I).
[0172] The invention further provides for a process of reacting a
chemical compound comprising subjecting said chemical compound to a
metathesis reaction in the presence of the aforementioned catalyst
systems.
[0173] The metathesis reactions can be ring-closing metatheses
(RCM), cross-metatheses (CM) or ring-opening metatheses (ROMP).
[0174] The catalyst systems of the invention are preferably used
for the metathesis of nitrile rubber. This is a
cross-metathesis.
[0175] In the catalyst system of the invention, the metathesis
catalyst and the salt or salts of the general formula (I) is/are
used in a weight ratio of salt(s):metathesis catalyst of from
0.01:1 to 10000:1, preferably from 0.1:1 to 1000:1, particularly
preferably from 0.5:1 to 500:1.
[0176] The salt or salts of the general formula (I) can be added in
a solvent or without solvent to the metathesis catalyst or its
solution in order to obtain the catalyst system of the
invention.
[0177] As solvent or dispersion medium in which the salt or salts
of the general formula (I) is/are added to the catalyst or its
solution, it is possible to use all known solvents. For the
addition of the salt to be effective, it is not absolutely
necessary for the salt to have a high solubility in the solvent.
Preferred solvents include but are not restricted to acetone,
benzene, chlorobenzene, chloroform, cyclohexane, dichloromethane,
dioxane, dimethylformamide, dimethylacetamide, dimethyl sulphone,
dimethyl sulphoxide, methyl ethyl ketone, tetrahydrofuran,
tetrahydropyran and toluene. The solvent is preferably inert
towards the metathesis catalyst.
[0178] If the catalyst systems of the invention are used for the
metathesis of nitrile rubber, the amount in which the salt or salts
of the general formula (I) is or are used is, based on the rubber
to be degraded, in the range from 0.0001 phr to 50 phr, preferably
from 0.001 phr to 35 phr (phr=parts by weight per 100 parts by
weight of rubber).
[0179] For the use for the NBR metathesis, too, the salt or salts
of the general formula (I) can be added in a solvent or without
solvent to a solution of the metathesis catalyst. As an alternative
thereto, it is also possible to add the salt or salts of the
general formula (I) directly to a solution of the nitrile rubber to
be degraded to which the metathesis catalyst is also added, so that
the entire catalyst system according to the invention is present in
the reaction mixture.
[0180] The amount of metathesis catalyst based on the nitrile
rubber used depends on the nature and the catalytic activity of the
specific catalyst. The amount of catalyst used is usually from 1 to
1000 ppm of noble metal, preferably from 2 to 500 ppm, in
particular from 5 to 250 ppm, based on the nitrile rubber used.
[0181] The NBR metathesis can be carried out in the absence or
presence of a coolefin. This is preferably a straight-chain or
branched C.sub.2-C.sub.16-olefin. Suitable coolefins are, for
example, ethylene, propylene, isobutene, styrene, 1-hexene and
1-octene. Preference is given to using 1-hexene or 1-octene. If the
coolefin is liquid (as in the case of, for example, 1-hexene), the
amount of coolefin is preferably in the range 0.2-20% by weight
based on the NBR used. If the coolefin is a gas, as in the case of,
for example, ethylene, the amount of coolefin is selected so that a
pressure in the range 1.times.10.sup.5 Pa-1.times.10.sup.7 Pa,
preferably a pressure in the range from 5.2.times.10.sup.5 Pa to
4.times.10.sup.6 Pa, is established in the reaction vessel at room
temperature.
[0182] The metathesis reaction can be carried out in a suitable
solvent which does not deactivate the catalyst used and also does
not adversely affect the reaction in any other way. Preferred
solvents include, but are not restricted to, dichloromethane,
benzene, toluene, methyl ethyl ketone, acetone, tetrahydrofuran,
tetrahydropyran, dioxane and cyclohexane. The particularly
preferred solvent is chlorobenzene. In some cases, when the
coolefin itself can function as solvent, e.g. in the case of
1-hexene, the addition of a further additional solvent can also be
omitted.
[0183] The concentration of the nitrile rubber used in the reaction
mixture of the metathesis is not critical, but care naturally has
to be taken to ensure that the reaction is not adversely affected
by an excessively high viscosity of the reaction mixture and the
mixing problems associated therewith. The concentration of NBR in
the reaction mixture is preferably in the range from 1 to 20% by
weight, particularly preferably in the range from 5 to 15% by
weight, based on the total reaction mixture.
[0184] The metathetic degradation is usually carried out at a
temperature in the range from 10.degree. C. to 150.degree. C.,
preferably at a temperature in the range from 20 to 100.degree.
C.
[0185] The reaction time depends on a number of factors, for
example, on the type of NBR, the type of catalyst, the catalyst
concentration used and the reaction temperature. The reaction is
typically complete within three hours under normal conditions. The
progress of the metathesis can be monitored by standard analytical
methods, e.g. by GPC measurement or by determination of the
viscosity.
[0186] As nitrile rubbers ("NBR"), it is possible to use copolymers
or terpolymers which comprise repeating units of at least one
conjugated diene, at least one .alpha.,.beta.-unsaturated nitrile
and, if desired, one or more further copolymerizable monomers in
the metathesis reaction.
[0187] The conjugated diene can be of any nature. Preference is
given to using (C.sub.4-C.sub.6) conjugated dienes. Particular
preference is given to 1,3-butadiene, isoprene,
2,3-dimethylbutadiene, piperylene or mixtures thereof. Very
particular preference is given to 1,3-butadiene and isoprene or
mixtures thereof. Especial preference is given to
1,3-butadiene.
[0188] As .alpha.,.beta.-unsaturated nitrile, it is possible to use
any known .alpha.,.beta.-unsaturated nitrile, preferably a
(C.sub.3-C.sub.5) .alpha.,.beta.-unsaturated nitrile such as
acrylonitrile, methacrylonitrile, ethacrylonitrile or mixtures
thereof. Particular preference is given to acrylonitrile.
[0189] A particularly preferred nitrile rubber is thus a copolymer
of acrylonitrile and 1,3-butadiene.
[0190] Apart from the conjugated diene and the
.alpha.,.beta.-unsaturated nitrile, it is possible to use one or
more further copolymerizable monomers known to those skilled in the
art, e.g. .alpha.,.beta.-unsaturated monocarboxylic or dicarboxylic
acids, their esters or amides. As .alpha.,.beta.-unsaturated
monocarboxylic or dicarboxylic acids, preference is given to
fumaric acid, maleic acid, acrylic acid and methacrylic acid. As
esters of .alpha.,.beta.-unsaturated carboxylic acids, preference
is given to using their alkyl esters and alkoxyalkyl esters.
Particularly preferred alkyl esters of .alpha.,.beta.-unsaturated
carboxylic acids are methyl acrylate, ethyl acrylate, butyl
acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl
methacrylate and octyl acrylate. Particularly preferred alkoxyalkyl
esters of .alpha.,.beta.-unsaturated carboxylic acids are
methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate and
methoxyethyl (meth)acrylate. It is also possible to use mixtures of
alkyl esters, e.g. those mentioned above, with alkoxyalkyl esters,
e.g. in the form of those mentioned above.
[0191] The proportions of conjugated diene and
.alpha.,.beta.-unsaturated nitrile in the NBR polymers to be used
can vary within wide ranges. The proportion of or of the sum of the
conjugated dienes is usually in the range from 40 to 90% by weight,
preferably in the range from 60 to 85% by weight, based on the
total polymer. The proportion of or of the sum of the
.alpha.,.beta.-unsaturated nitriles is usually from 10 to 60% by
weight, preferably from 15 to 40% by weight, based on the total
polymer. The proportions of the monomers in each case add up to
100% by weight. The additional monomers can be present in amounts
of from 0 to 40% by weight, preferably from 0.1 to 40% by weight,
particularly preferably from 1 to 30% by weight, based on the total
polymer. In this case, corresponding proportions of the conjugated
diene or dienes and/or of the .alpha.,.beta.-unsaturated nitrile or
nitriles are replaced by the proportions of the additional
monomers, with the proportions of all monomers in each case adding
up to 100% by weight.
[0192] The preparation of nitrile rubbers by polymerization of the
abovementioned monomers is adequately known to those skilled in the
art and is comprehensively described in the polymer literature.
[0193] Nitrile rubbers which can be used for the purposes of the
invention are also commercially available, e.g. as products from
the product range of the trade names Perbunan.RTM. and Krynac.RTM.
from Lanxess Deutschland GmbH.
[0194] The nitrile rubbers used for the metathesis have a Mooney
viscosity (ML 1+4 at 100.degree. C.) in the range from 30 to 70,
preferably from 30 to 50. This corresponds to a weight average
molecular weight M.sub.w in the range 200 000-500 000, preferably
in the range 200 000-400 000. The nitrile rubbers used also have a
polydispersity PDI=M.sub.w/M.sub.n, where M.sub.w is the weight
average molecular weight and M.sub.n is the number average
molecular weight, in the range 2.0-6.0 and preferably in the range
2.0-4.0.
[0195] The determination of the Mooney viscosity is carried out in
accordance with ASTM standard D 1646.
[0196] The nitrile rubbers obtained by the metathesis process
according to the invention have a Mooney viscosity (ML 1+4 at
100.degree. C.) in the range 5-30, preferably 5-20. This
corresponds to a weight average molecular weight M.sub.w in the
range 10 000-200 000, preferably in the range 10 000-150 000. The
nitrile rubbers obtained also have a polydispersity
PDI=M.sub.w/M.sub.n, where M.sub.n is the number average molecular
weight, in the range 1.5-4.0, preferably in the range 1.7-3.
[0197] The metathetic degradation in the presence of the catalyst
system of the invention can be followed by a hydrogenation of the
degraded nitrile rubbers obtained. This can be carried out in the
manner known to those skilled in the art.
[0198] It is possible to carry out the hydrogenation with use of
homogeneous or heterogeneous hydrogenation catalysts. It is also
possible to carry out the hydrogenation in situ, i.e. in the same
reaction vessel in which the metathetic degradation has previously
also been carried out and without the necessity of isolating the
degraded nitrile rubber. The hydrogenation catalyst is simply added
to the reaction vessel.
[0199] The catalysts used are usually based on rhodium, ruthenium
or titanium, but it is also possible to use platinum, iridium,
palladium, rhenium, ruthenium, osmium, cobalt or copper either as
metal or preferably in the form of metal compounds (cf., for
example, U.S. Pat. No. 3,700,637, DE-A-25 39 132, EP-A-0 134 023,
DE-A-35 41 689, DE-A-35 40 918, EP-A-0 298 386, DE-A-35 29 252,
DE-A-34 33 392, U.S. Pat. No. 4,464,515 and U.S. Pat. No.
4,503,196).
[0200] Suitable catalysts and solvents for a hydrogenation in the
homogeneous phase are described below and are also known from
DE-A-25 39 132 and EP-A-0 471 250.
[0201] The selective hydrogenation can be achieved, for example, in
the presence of a rhodium- or ruthenium-containing catalyst. It is
possible to use, for example, a catalyst of the general formula
(R.sub.m.sup.1B).sub.1M X.sub.n. where M is ruthenium or rhodium,
the radicals R.sup.1 are identical or different and are each a
C.sub.1-C.sub.8-alkyl group, a C.sub.4-C.sub.8-cycloalkyl group, a
C.sub.6-C.sub.15-aryl group or a C.sub.7-C.sub.15-aralkyl group. B
is phosphorus, arsenic, sulphur or a sulphoxide group S.dbd.O, X is
hydrogen or an anion, preferably halogen and particularly
preferably chlorine or bromine, 1 is 2, 3 or 4, m is 2 or 3 and n
is 1, 2 or 3, preferably 1 or 3. Preferred catalysts are
tris(triphenylphosphine)rhodium(I) chloride,
tris(triphenylphosphine)rhodium(III) chloride and tris(dimethyl
sulphoxide)rhodium(III) chloride and also
tetrakis(triphenylphosphine)rhodium hydride of the formula
(C.sub.6H.sub.5).sub.3P).sub.4RhH and the corresponding compounds
in which the triphenylphosphine has been completely or partly
replaced by tricyclohexylphosphine. The catalyst can be utilized in
small amounts. An amount in the range 0.01-1% by weight, preferably
in the range 0.03-0.5% by weight and particularly preferably in the
range 0.1-0.3% by weight, based on the weight of the polymer, is
suitable.
[0202] It is usually appropriate to use the catalyst together with
a cocatalyst which is a ligand of the formula R.sub.m.sup.1B, where
R.sup.1, m and B have the meanings given above for the catalyst.
Preference is given to m being 3, B being phosphorus and the
radicals R.sup.1 can be identical or different. Preference is given
to cocatalysts having trialkyl, tricycloalkyl, triaryl, triaralkyl,
diaryl-monoalkyl, diaryl-monocycloalkyl, dialkyl-monoaryl,
dialkyl-monocycloalkyl, dicycloalkyl-monoaryl or
dicycloalkyl-monoaryl radicals.
[0203] Examples of cocatalysts may be found in, for example, U.S.
Pat. No. 4,631,315. A preferred cocatalyst is triphenylphosphine.
The cocatalyst is preferably used in amounts in the range 0.3-5% by
weight, preferably in the range 0.5-4% by weight, based on the
weight of the nitrile rubber to be hydrogenated. Furthermore, the
weight ratio of the rhodium-containing catalyst to the cocatalyst
is preferably in the range from 1:3 to 1:55, more preferably in the
range from 1:5 to 1:45. Based on 100 parts by weight of the nitrile
rubber to be hydrogenated, it is appropriate to use from 0.1 to 33
parts by weight of the cocatalyst, preferably from 0.5 to 20 parts
by weight and very particularly preferably from 1 to 5 parts by
weight, in particular more than 2 but less than 5 parts by weight
of cocatalyst, per 100 parts by weight of the nitrile rubber to be
hydrogenated.
[0204] The practical implementation of this hydrogenation is
adequately known to those skilled in the art from U.S. Pat. No.
6,683,136. It is usually carried out by treating the nitrile rubber
to be hydrogenated in a solvent such as toluene or
monochlorobenzene with hydrogen at a temperature in the range from
100 to 150.degree. C. and a pressure in the range from 50 to 150
bar for from 2 to 10 hours.
[0205] For the purposes of the present invention, hydrogenation is
a reaction of the double bonds present in the starting nitrile
rubber to an extent of at least 50%, preferably 70-100%,
particularly preferably 80-100%.
[0206] When heterogeneous catalysts are used, these are usually
supported catalysts based on palladium which are, for example,
supported on carbon, silica, calcium carbonate or barium
sulphate.
[0207] After conclusion of the hydrogenation, a hydrogenated
nitrile rubber having a Mooney viscosity (ML 1+4 at 100.degree.
C.), measured in accordance with ASTM standard D 1646, in the range
10-50, preferably from 10 to 30, is obtained. This corresponds to a
weight average molecular weight M.sub.w in the range 2000-400 000
g/mol, preferably in the range 20 000-200 000. The hydrogenated
nitrile rubbers obtained also have a polydispersity
PDI=M.sub.w/M.sub.n, where M.sub.w is the weight average molecular
weight and M.sub.n is the number average molecular weight, in the
range 1-5 and preferably in the range 1.5-3.
[0208] The negative effect observed when using copper salts in the
nitrile rubber metathesis surprisingly does not occur when salts of
the general formula (I) are used.
[0209] However, the catalyst system of the invention can not only
be used successfully for the metathetic degradation of nitrile
rubbers but can also be used universally for other metathesis
reactions, e.g. for ring-closing metatheses such as the ring
closure of diethyl diallyl malonate.
[0210] As a result of the use of the novel catalyst systems
comprising catalyst and one or more salts of the general formula
(I), the amount of the metathesis catalyst and thus the amount of
noble metal can be significantly reduced at comparable reaction
times compared to analogous metathesis reactions in which only the
catalyst, i.e. without salts, is used. When comparable noble metal
contents are used, the reaction times are substantially shortened
by the salt additions. When the catalyst systems are used for the
degradation of nitrile rubbers, degraded nitrile rubbers having
significantly lower molecular weights M.sub.w and M.sub.n can be
obtained.
EXAMPLES
[0211] The following experiments show that the activity of the
catalyst can be increased when it is used in combination with salt
additions.
[0212] The following catalysts were used for this purpose:
##STR27##
[0213] The Grubbs II catalyst was procured from Materia
(Pasadena/California). ##STR28##
[0214] The Hoveyda catalyst was procured from Aldrich under the
product number 569755. ##STR29##
[0215] The Grela catalyst was prepared by the method published in
J. Org. Chem. 2004, 69, 6894-6896. ##STR30##
[0216] The Buchmeiser Nuyken catalyst was prepared as described in
Chemistry European Journal 2004, 10(3), 777-785.
General Method for the Metathetic Degradation of Nitrile Rubber
("NBR")
[0217] The degradation reactions described below in the trials 1 to
6 were carried out using the nitrile rubber Perbunan.RTM. NT 3435
from Lanxess Deutschland GmbH. This nitrile rubber had the
following characteristic properties: TABLE-US-00001 Acrylonitrile
content: 35% by weight Mooney viscosity (ML 1 + 4 @100.degree. C.):
34 Mooney units Residual moisture content: 1.8% by weight M.sub.w:
240 000 g/mol M.sub.n: 100 000 g/mol PDI (M.sub.w/M.sub.n): 2.4
[0218] The metathetic degradation was in each case carried out
using 293.3 g of chlorobenzene (herein after referred to as
"MCB"/from Aldrich) which had been distilled and made inert by
passing argon through it at room temperature before use. 40 g of
NBR were dissolved therein at room temperature over a period of 10
hours. 0.8 g (2 phr) of 1-hexene was in each case added to the
NBR-containing solution and the mixture was stirred for 30 minutes
to homogenize it.
[0219] The metathesis reaction was carried out at room temperature
using the amounts of starting materials indicated below in Table 1.
The Ru catalysts were in each case dissolved in 20 g of MCB at room
temperature under argon. The addition of the catalyst solutions to
the NBR solutions in MCB was carried out immediately after the
preparation of the catalyst solutions. After the reaction times
indicated below in Table 2, about 5 ml were in each case taken from
the reaction solutions and immediately admixed with about 0.2 ml of
ethyl vinyl ether to stop the reaction and subsequently dilute it
with 5 ml of DMAc (N,N-dimethylacetamide) from Aldrich. 2 ml of the
solutions were in each case placed in a GPC bottle and diluted with
DMAc to 3 ml. Before carrying out the GPC analysis, the solutions
were in each case filtered by means of a 0.2 .mu.m syringe filter
made of Teflon (Chromafil PTFE 0.2 .mu.m; from Machery-Nagel). The
GPC analysis was subsequently carried out using a Waters instrument
(Mod. 510). The analysis was carried out using a combination of 4
columns from Polymer Laboratories: 1) PLgel 5 .mu.M Mixed-C,
300.times.7.5 mm, 2) PLgel 5 .mu.m Mixed-C, 300.times.7.5 mm, 3)
PLgel 3 .mu.m Mixed-E, 300.times.7.5 mm, and 4) PLgel 3 .mu.m
Mixed-E, 300.times.7.5 mm.
[0220] The calibration of the GPC columns was carried out using
linear poly(methyl methacrylate) from Polymer Standards Services.
An RI detector from Waters (Waters 410) was used as detector. The
analysis was carried out at a flow rate of 0.5 ml/min using DMAc as
eluent. The GPC curves were evaluated using software from
Millenium.
[0221] The following characteristic properties were determined by
means of GPC analysis both for the original NBR rubber (before
degradation) and for the degraded nitrile rubbers:
M.sub.w [kg/mol]: weight average molar mass
M.sub.n [kg/mol]: number average molar mass
[0222] PDI: width of the molar mass distribution (M.sub.w/M.sub.n)
TABLE-US-00002 TABLE 1 Salt Amount Trial Catalyst Type [phr]
Solvent 1.01 Grubbs (II) -- -- -- 1.02 Grubbs (II) LiBr 0.023 DMAC
1.03 Grubbs (II) LiBr 0.00475 DMAC 1.04 Grubbs (II) LiBr 0.5 --
1.05 Grubbs (II) LiBr 5.08 -- 1.06 Grubbs (II) CsBr 12.45 -- 1.07
Grubbs (II) LiCl 2.55 -- 1.08 Grubbs (II) [Bu.sub.4N].sup.+Cl.sup.-
16.25 -- 1.09 Grubbs (II) [Bu.sub.4N].sup.+Br.sup.- 18.85 -- 1.10
Grubbs (II) [Bu.sub.4N].sup.+J.sup.- 21.60 -- 1.11. Grubbs (II)
[Bu.sub.4P].sup.+Cl.sup.- 17.23 -- 1.12. Grubbs (II)
[Bu.sub.4P].sup.+Br.sup.- 19.85 -- 1.13 Grubbs (II)
[Ph.sub.4P].sup.+Br.sup.- 24.53 -- 1.14 Grubbs (II)
[Oc.sub.4P].sup.+Br.sup.- 32.98 -- 1.15 Grubbs (II)
[Bu.sub.4N].sup.+SCN.sup.- 17.58 -- 1.16 Grubbs (II)
[Oc.sub.4N].sup.+Cl.sup.- 2.93 -- 1.17 Grubbs (II) Na.sub.2SO.sub.4
8.30 1.18 Grubbs (II) LiNO.sub.3 4.03 -- 1.19 Grubbs (II)
NaNO.sub.2 4.03 2.01 Hoveyda -- -- -- 2.02 Hoveyda LiBr 5.08 --
3.01 Buchmeiser-Nuyken -- -- -- 3.02 Buchmeiser-Nuyken LiBr 5.08 --
4.01 Grela -- -- -- 4.02 Grela LiBr 5.08 -- 5.01 Hoveyda -- 5.02
Hoveyda CuCl 2.32 6.01 Grela -- -- -- 6.02 Grela CuCl 2.32 --
[0223] 1.00. Salt Additions when Using the Grubbs II Catalyst
TABLE-US-00003 1.01. Comparative experiment: Grubbs II catalyst
without salt addition Grubbs II catalyst Salt addition Tem- (MW:
848.33 g/mol) Salt Solvent pera- Amount Amount Ru Amount Amount
ture [mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05
60 -- -- -- -- 23 Reaction time [min.] Analytical data 0 30 60 185
425 1300 M.sub.w [kg/mol] 240 185 165 77 60 53 M.sub.n [kg/mol] 100
84 78 38 35 29 PDI 2.4 2.13 2.11 2.03 1.71 1.82
[0224] TABLE-US-00004 1.02. Grubbs II catalyst with 0.023 phr of
lithium bromide dissolved in dimethylacetamide Salt addition Tem-
Grubbs II catalyst Salt Solvent pera- Amount Amount Ru Amount
Amount ture [mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 20
0.05 60 LiBr 0.023 DMAc 5.0 23 Reaction time [min.] Analytical data
0 30 60 185 425 1300 M.sub.w [kg/mol] 240 140 78 42 23 22 M.sub.n
[kg/mol] 100 66 40 24 13 14 PDI 2.4 2.12 1.95 1.75 1.76 1.58
[0225] TABLE-US-00005 1.03. Grubbs II catalyst with 0.00475 phr of
lithium bromide dissolved in dimethylacetamide Salt addition Tem-
Grubbs II catalyst Salt Solvent pera- Amount Amount Ru Amount
Amount ture [mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 20
0.05 60 LiBr 0.00475 DMAc 0.58 23 Reaction time [min.] Analytical
data 0 30 60 185 425 1300 M.sub.w [kg/mol] 240 138 105 -- 52 47
M.sub.n [kg/mol] 100 69 56 -- 31 28 PDI 2.4 2.0 1.88 -- 1.68
1.7
[0226] TABLE-US-00006 1.04. Grubbs II catalyst with 0.5 phr of
lithium bromide Salt addition Tem- Grubbs II catalyst Salt Solvent
pera- Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type
[phr] Type [phr] [.degree. C.] 20 0.05 60 LiBr 0.5 -- -- 23
Reaction time [min.] Analytical data 0 30 60 185 425 1300 M.sub.w
[kg/mol] 240 -- 61 40 27 -- M.sub.n [kg/mol] 100 -- 34 25 16 -- PDI
2.4 -- 1.7 1.6 1.7 --
[0227] TABLE-US-00007 1.05. Grubbs II catalyst with 5.08 phr of
lithium bromide Salt addition Tem- Grubbs II catalyst Salt Solvent
pera- Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type
[phr] Type [phr] [.degree. C.] 20 0.05 60 LiBr 5.08 -- -- 23
Reaction time [min.] Analytical data 0 30 60 185 425 1300 M.sub.w
[kg/mol] 240 140 66 41 23 -- M.sub.n [kg/mol] 100 78 40 24 13 --
PDI 2.4 2.12 1.95 1.71 1.76 --
[0228] TABLE-US-00008 1.06. Grubbs II catalyst with 12.45 phr of
caesium bromide Salt addition Tem- Grubbs II catalyst Salt Solvent
pera- Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type
[phr] Type [phr] [.degree. C.] 20 0.05 60 CsBr 12.45 -- -- 23
Reaction time [min.] Analytical data 0 30 60 185 425 1300 M.sub.w
[kg/mol] 240 144 109 61 52 -- M.sub.n [kg/mol] 100 64 55 35 25 --
PDI 2.4 2.25 1.99 1.77 2.06 --
[0229] TABLE-US-00009 1.07. Grubbs II catalyst with 2.55 phr of
lithium chloride Salt addition Tem- Grubbs II catalyst Salt Solvent
pera- Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type
[phr] Type [phr] [.degree. C.] 20 0.05 60 LiCl 2.55 -- -- 23
Reaction time [min.] Analytical data 0 30 60 185 425 1300 M.sub.w
[kg/mol] 240 170 111 -- 50 -- M.sub.n [kg/mol] 100 75 54 -- 29 --
PDI 2.4 2.3 2.1 -- 1.7 --
[0230] TABLE-US-00010 1.08. Grubbs II catalyst with 16.25 phr of
tetrabutylammonium chloride Salt addition Tem- Grubbs II catalyst
Salt Solvent pera- Amount Amount Ru Amount Amount ture [mg] [phr]
[ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60 Bu.sub.4NCl
16.25 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 -- 91 51 38 -- M.sub.n [kg/mol] 100 -- 51
30 23 -- PDI 2.4 -- 1.8 1.7 1.7 --
[0231] TABLE-US-00011 1.09 Grubbs II catalyst with 18.85 phr of
tetrabutylammonium bromide Salt addition Tem- Grubbs II catalyst
Salt Solvent pera- Amount Amount Ru Amount Amount ture [mg] [phr]
[ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60 Bu.sub.4NBr
18.85 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 134 78 37 22 -- M.sub.n [kg/mol] 100 70
45 21 13 -- PDI 2.4 1.91 1.73 1.75 1.75 --
[0232] TABLE-US-00012 1.10 Grubbs II catalyst with 21.6 phr of
tetrabutylammonium iodide Salt addition Tem- Grubbs II catalyst
Salt Solvent pera- Amount Amount Ru Amount Amount ture [mg] [phr]
[ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60 Bu.sub.4NI
21.60 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 -- 136 -- -- -- M.sub.n [kg/mol] 100 --
64 -- -- -- PDI 2.4 -- 2.14 -- -- --
[0233] TABLE-US-00013 1.11 Grubbs II catalyst with 17.23 phr of
tetrabutylphosphonium chloride Salt addition Tem- Grubbs II
catalyst Salt Solvent pera- Amount Amount Ru Amount Amount ture
[mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60
Bu.sub.4PCl 17.23 -- -- 23 Reaction time [min.] Analytical data 0
30 60 185 425 1300 M.sub.w [kg/mol] 240 175 -- -- -- -- M.sub.n
[kg/mol] 100 83 -- -- -- -- PDI 2.4 2.11 -- -- -- --
[0234] TABLE-US-00014 1.12. Grubbs II catalyst with 19.85 phr of
tetrabutylphosphonium bromide Salt addition Tem- Grubbs II catalyst
Salt Solvent pera- Amount Amount Ru Amount Amount ture [mg] [phr]
[ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60 Bu.sub.4PBr
19.85 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 102 58 34 25 -- M.sub.n [kg/mol] 100 48
32 20 14 -- PDI 2.4 2.14 1.84 1.69 1.73 --
[0235] TABLE-US-00015 1.13. Grubbs II catalyst with 24.53 phr of
tetraphenylphosphonium bromide Salt addition Tem- Grubbs II
catalyst Salt Solvent pera- Amount Amount Ru Amount Amount ture
[mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60
Ph.sub.4PBr 24.53 -- -- 23 Reaction time [min.] Analytical data 0
30 60 185 425 1300 M.sub.w [kg/mol] 240 183 130 -- -- -- M.sub.n
[kg/mol] 100 84 66 -- -- -- PDI 2.4 2.1 2.0 -- -- --
[0236] TABLE-US-00016 1.14. Grubbs II catalyst with 32.98 phr of
tetraoctylphosphonium bromide Salt addition Tem- Grubbs II catalyst
Salt Solvent pera- Amount Amount Ru Amount Amount ture [mg] [phr]
[ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60 Oc.sub.4PBr
32.98 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 170 85 44 30 -- M.sub.n [kg/mol] 100 72
49 25 18 -- PDI 2.4 2.37 1.73 1.78 1.65 --
[0237] TABLE-US-00017 1.15. Grubbs II catalyst with 17.58 phr of
tetrabutylammonium thiocyanate Salt addition Tem- Grubbs II
catalyst Salt Solvent pera- Amount Amount Ru Amount Amount ture
[mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60
Bu.sub.4NSCN 17.58 -- -- 23 Reaction time [min.] Analytical data 0
30 60 185 425 1300 M.sub.w [kg/mol] 240 -- 159 -- -- -- M.sub.n
[kg/mol] 100 -- 71 -- -- -- PDI 2.4 -- 2.25 -- -- --
[0238] TABLE-US-00018 1.16. Grubbs II catalyst with 2.93 phr of
tetraoctylammonium chloride Salt addition Tem- Grubbs II catalyst
Salt Solvent pera- Amount Amount Ru Amount Amount ture [mg] [phr]
[ppm] Type [phr] Type [phr] [.degree. C.] 20 0.05 60 Oc.sub.4NCl
2.93 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 149 112 57 40 -- M.sub.n [kg/mol] 100 69
56 35 22 -- PDI 2.4 2.2 2.0 1.7 1.8 --
[0239] TABLE-US-00019 1.17. Grubbs II catalyst with 8.3 phr of
sodium sulphate Salt addition Tem- Grubbs II catalyst Salt Solvent
pera- Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type
[phr] Type [phr] [.degree. C.] 20 0.05 60 Na.sub.2SO.sub.4 8.30 --
-- 23 Reaction time [min.] Analytical data 0 30 60 185 425 1300
M.sub.w [kg/mol] 240 110 78 55 47 -- M.sub.n [kg/mol] 100 55 44 30
26 -- PDI 2.4 2.0 1.8 1.8 1.8 --
[0240] TABLE-US-00020 1.18. Grubbs II catalyst with 4.03 phr of
lithium nitrate Salt addition Tem- Grubbs II catalyst Salt Solvent
pera- Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type
[phr] Type [phr] [.degree. C.] 20 0.05 60 LiNO.sub.3 4.03 -- -- 23
Reaction time [min.] Analytical data 0 30 60 185 425 1300 M.sub.w
[kg/mol] 240 182 106 66 57 -- M.sub.n [kg/mol] 100 75 53 37 32 --
PDI 2.4 2.43 2.00 1.78 1.78 --
[0241] TABLE-US-00021 1.19. Grubbs II catalyst with 4.03 phr of
sodium nitrite Salt addition Tem- Grubbs II catalyst Salt Solvent
pera- Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type
[phr] Type [phr] [.degree. C.] 20 0.05 60 NaNO.sub.2 4.03 -- -- 23
Reaction time [min.] Analytical data 0 30 60 185 425 1300 M.sub.w
[kg/mol] 240 184 133 -- 56 -- M.sub.n [kg/mol] 100 77 63 -- 32 --
PDI 2.4 2.38 2.11 -- 1.75 --
[0242] As a result of the salt additions in the trials 1.02. to
1.19., the molecular weights M.sub.w and M.sub.n were significantly
reduced compared to the comparative experiment without salt
addition (trial 1.01.). The salt additions thus improve the
efficiency of the Grubbs II catalyst. In addition, the degraded
nitrite rubbers obtained in the trials 1.02. to 1.19. were
gel-free.
[0243] Salt Additions when Using the Hovevda Catalyst
TABLE-US-00022 2.01. Comparative experiment: Hoveyda catalyst
without salt addition Hoveyda catalyst Salt addition Tem- (MW:
626.14 g/mol) Salt Solvent pera- Amount Amount Ru Amount Amount
ture [mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 8 0.02
32.3 -- -- -- -- 23 Reaction time [min.] Analytical data 0 30 60
185 425 1300 M.sub.w [kg/mol] 240 85 60 58 55 -- M.sub.n [kg/mol]
100 50 32 31 31 -- PDI 2.4 1.7 1.9 1.8 1.7 --
[0244] TABLE-US-00023 2.02. Hoveyda catalyst with 5.08 ppm of
lithium bromide Hoveyda catalyst Salt addition Tem- (MW: 626.14
g/mol) Salt Solvent pera Amount Amount Ru Amount Amount ture [mg]
[phr] [ppm] Type [phr] Type [phr] [.degree. C.] 8 0.02 32.3 LiBr
5.08 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 60 36 28 25 -- M.sub.n [kg/mol] 100 26 20
15 15 -- PDI 2.4 2.3 1.8 1.9 1.7 --
[0245] As a result of the salt addition in trial 2.02., the
molecular weights M.sub.w and M.sub.n were significantly reduced
compared to the comparative experiments without salt addition
(trial 2.01.). The salt addition thus improved the efficiency of
the Hoveyda catalyst. In addition, the degraded nitrile rubbers
obtained in the trial 2.02. were gel-free.
[0246] 3.00. Salt Additions when Using the Buchmeiser-Nuyken
Catalyst TABLE-US-00024 3.01. Comparative experiment:
Buchmeiser-Nuyken catalyst without salt addition Buchmeiser-Nuyken
catalyst Salt addition Tem- (MW: 781.14 g/mol) Salt Solvent pera
Amount Amount Ru Amount Amount ture [mg] [phr] [ppm] Type [phr]
Type [phr] [.degree. C.] 36.8 0.0092 119 -- -- -- -- 23 Reaction
time [min.] Analytical data 0 30 60 185 425 1300 M.sub.w [kg/mol]
240 221 219 185 170 -- M.sub.n [kg/mol] 100 79 78 62 58 -- PDI 2.4
2.8 2.8 2.9 2.9 --
[0247] TABLE-US-00025 3.02. Buchmeiser-Nuyken catalyst with 5.08
phr of lithium bromide Buchmeiser-Nuyken Salt addition Tem-
catalyst Salt Solvent pera Amount Amount Ru Amount Amount ture [mg]
[phr] [ppm] Type [phr] Type [phr] [.degree. C.] 36.8 0.0092 119
LiBr 5.08 -- -- 23 Reaction time [min.] Analytical data 0 30 60 185
425 1300 M.sub.w [kg/mol] 240 117 43 23 17 -- M.sub.n [kg/mol] 100
50 24 14 10 -- PDI 2.4 2.3 1.8 1.6 1.6 --
[0248] As a result of the salt addition in trial 3.02., the
molecular weights M.sub.w and M.sub.n were significantly reduced
compared to the comparative experiments without salt addition
(trial 3.01.). The salt addition thus improved the efficiency of
the Buchmeiser-Nuyken catalyst. In addition, the degraded nitrile
rubbers obtained in the trial 3.02. were gel-free.
[0249] 4.00. Salt Additions when Using the Grela Catalyst
TABLE-US-00026 4.01. Comparative experiment: Grela catalyst without
salt addition Grela catalyst Salt addition Tem- (MW: 671.13 g/mol)
Salt Solvent pera Amount Amount Ru Amount Amount ture [mg] [phr]
[ppm] Type [phr] Type [phr] [.degree. C.] 15.8 0.0395 23.8 -- -- --
-- 23 Reaction time [min.] Analytical data 0 30 60 185 425 1300
M.sub.w [kg/mol] 240 37 35 33 31 -- M.sub.n [kg/mol] 100 23 22 22
20 -- PDI 2.4 1.61 1.59 1.50 1.55 --
[0250] TABLE-US-00027 4.02. Grela catalyst with addition of 5.08
phr of lithium bromide Grela catalyst Salt addition Tem- (MW:
671.13 g/mol) Salt Solvent pera Amount Amount Ru Amount Amount ture
[mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 15.8 0.0395
23.8 LiBr 5.08 -- -- 23 Reaction time [min.] Analytical data 0 30
60 185 425 1300 M.sub.w [kg/mol] 240 33 31 29 24 -- M.sub.n
[kg/mol] 100 2.1 20 19 16 -- PDI 2.4 1.57 1.55 1.53 1.50 --
[0251] As a result of the salt addition in trial 4.02., the
molecular weights M.sub.w and M.sub.n were reduced compared to the
comparative experiments without salt addition (trial 4.01.). The
salt addition thus improved the efficiency of the Grela catalyst.
In addition, the degraded nitrile rubbers obtained in the trial
4.02. were gel-free.
[0252] 5.0 Comparative Experiments: Hoveyda Catalyst without and
with Addition of 2.32 phr of CuCl TABLE-US-00028 5.01 Hoveyda
catalyst without addition of CuCl Hoveyda catalyst Tem- (MW: 626.14
g/mol) Salt addition pera Amount Amount Ru Amount Amount ture [mg]
[phr] [ppm] Type [phr] Type [phr] [.degree. C.] 14.7 0.0368 2.37 --
-- -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 42 42 41 39 -- M.sub.n [kg/mol] 100 28 24
23 23 -- PDI 2.4 1.5 1.75 1.78 1.69 --
[0253] TABLE-US-00029 5.02 Hoveyda catalyst with addition of 2.32
phr of copper(I) chloride Hoveyda catalyst Salt addition Tem- (MW:
626.14 g/mol) Salt Solvent pera Amount Amount Ru Amount Amount ture
[mg] [phr] [ppm] Type [phr] Type [phr] [.degree. C.] 14.7 0.0368
2.37 CuCl 2.32 -- -- 23 Reaction time [min.] Analytical data 0 30
60 185 425 1300 M.sub.w [kg/mol] 240 104 92 90 93 -- M.sub.n
[kg/mol] 100 58 54 53 54 -- PDI 2.4 1.79 1.70 1.69 1.72 --
[0254] Comparison of the trials 5.01 and 5.02 shows that the
metathetic degradation using the Hoveyda catalyst proceeds even
worse as a result of the addition of CuCl than when an additive is
entirely dispensed with. When CuCl is added, both the mean
molecular weight M.sub.w and also M.sub.n are more than twice as
high after the same reaction times compared to the values of
M.sub.w and M.sub.n achieved without salt addition.
[0255] 6.0 Comparative Experiments: Grela Catalyst without and with
Addition of 2.32 phr of CuCl TABLE-US-00030 6.01 Grela catalyst
without salt addition Grela catalyst Salt addition Tem- (MW: 671.13
g/mol) Salt Solvent pera Amount Amount Ru Amount Amount ture [mg]
[phr] [ppm] Type [phr] Type [phr] [.degree. C.] 15.8 0.0395 2.38 --
-- -- -- 23 Reaction time [min.] Analytical data 0 30 60 185 425
1300 M.sub.w [kg/mol] 240 37 35 33 31 -- M.sub.n [kg/mol] 100 23 22
22 20 -- PDI 2.4 1.61 1.59 1.50 1.55 --
[0256] TABLE-US-00031 6.02 Grela catalyst with addition of 2.32 phr
of CuCl Grela catalyst Salt addition Tem- (MW: 671.13 g/mol) Salt
Solvent pera Amount Amount Ru Amount Amount ture [mg] [phr] [ppm]
Type [phr] Type [phr] [.degree. C.] 15.8 0.0395 2.38 CuCl 2.32 --
-- 23 Reaction time [min.] Analytical data 0 30 60 185 425 1300
M.sub.w [kg/mol] 240 101 96 94 100 -- M.sub.n [kg/mol] 100 58 53 55
58 -- PDI 2.4 1.74 1.81 1.71 1.72 --
[0257] Comparison of the trials 7.01 and 7.02 shows that the
metathetic degradation using the Grela catalyst proceeds even worse
as a result of the addition of CuCl than when an additive is
entirely dispensed with. When CuCl is added, both the mean
molecular weight M.sub.w and also M.sub.n are more than twice as
high after the same reaction times compared to the values of
M.sub.w and M.sub.n achieved without salt addition.
Example 7
Use of LiBr for the Ring-Closing Metathesis of Diethyl
Diallylmalonate
[0258] The ring-closing metathesis of diethyl diallylmalonate was
carried out once without and once with 1 mg of LiBr (Examples 7.01
and 7.02) and also once without and once with 1 mg of CsBr
(Examples 8.01 and 8.02).
[0259] To carry out the experiments, 10 mg of Grubbs II catalyst
were in each case placed in an NMR tube. In the examples according
to the invention, which were carried out with additions of LiBr
(Example 7.02) or CsBr (Example 8.02), 1 mg of LiBr or 1 mg of CsBr
were weighed into the NMR tube in addition to the Grubbs II
catalyst (10 mg). Subsequently, firstly 0.3 ml of chlorobenzene and
then 0.2 ml of CDCl.sub.3 were added at room temperature by means
of a syringe. The contents of the NMR tube were mixed by shaking.
After 2 minutes in each case, 0.15 ml of diethyl diallylmalonate
was added by means of a syringe. The reaction conditions were
determined by means of .sup.1H-NMR spectroscopy at room
temperature.
[0260] The following table clearly shows the accelerating effect of
the addition of LiBr on the ring-closing methathesis of diethyl
diallylmalonate. TABLE-US-00032 With salt addition (7.02) Without
salt addition (7.01) 1 mg of LiBr Time [min.] Conversion [%]
Conversion [%] 0 0 0 30 21.3 55.4 60 57.7 100
Example 8
Use of CsBr for the Ring-Closing Metathesis of Diethyl
Diallylmalonate
[0261] The experiments were carried out in a manner analogous to
Example 7 using 1 mg of CsBr instead of 1 mg of LiBr.
TABLE-US-00033 With salt addition (8.02) Without salt addition
(8.01) 1 mg of CsBr Time [min.] Conversion [%] Conversion [%] 0 0 0
15 13.4 16.5 30 25.3 40.3 60 46.5 68.9 90 71.9 84.7 150 96.2
100
* * * * *