U.S. patent application number 11/094102 was filed with the patent office on 2005-11-24 for latent, high-activity olefin metathesis catalysts containing an n-heterocyclic carbene ligand.
This patent application is currently assigned to California Institute of Technology. Invention is credited to Grubbs, Robert H., Hejl, Andrew, Sanders, Daniel, Schrodi, Yann, Trimmer, Mark S., Ung, Thay.
Application Number | 20050261451 11/094102 |
Document ID | / |
Family ID | 35064307 |
Filed Date | 2005-11-24 |
United States Patent
Application |
20050261451 |
Kind Code |
A1 |
Ung, Thay ; et al. |
November 24, 2005 |
Latent, high-activity olefin metathesis catalysts containing an
N-heterocyclic carbene ligand
Abstract
The invention provides novel organometallic complexes useful as
olefin metathesis catalysts. The complexes have an N-heterocyclic
carbene ligand and a chelating carbene ligand associated with a
Group 8 transition metal center. The molecular structure of the
complexes can be altered so as to provide a substantial latency
period. The complexes are particularly useful in catalyzing ring
closing metathesis of acyclic olefins and ring opening metathesis
polymerization of cyclic olefins.
Inventors: |
Ung, Thay; (Los Angeles,
CA) ; Schrodi, Yann; (Pasadena, CA) ; Trimmer,
Mark S.; (Monrovia, CA) ; Hejl, Andrew;
(Pasadena, CA) ; Sanders, Daniel; (Pasadena,
CA) ; Grubbs, Robert H.; (South Pasadena,
CA) |
Correspondence
Address: |
REED INTELLECTUAL PROPERTY LAW GROUP
1400 PAGE MILL ROAD
PALO ALTO
CA
94304-1124
US
|
Assignee: |
California Institute of
Technology
Pasadena
CA
|
Family ID: |
35064307 |
Appl. No.: |
11/094102 |
Filed: |
March 29, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60557742 |
Mar 29, 2004 |
|
|
|
60604158 |
Aug 23, 2004 |
|
|
|
Current U.S.
Class: |
526/171 ;
526/172; 546/2; 548/101 |
Current CPC
Class: |
C08G 61/06 20130101;
C08G 61/02 20130101; C07F 15/0046 20130101; C08G 2261/11 20130101;
C08G 2261/3325 20130101; C07C 67/333 20130101; C08G 2261/418
20130101; C08F 132/08 20130101; C07D 493/10 20130101 |
Class at
Publication: |
526/171 ;
526/172; 546/002; 548/101 |
International
Class: |
C08F 004/80; C07F
015/00 |
Claims
We claim:
1. An organometallic complex comprising a Group 8 transition metal
having an N-heterocyclic carbene ligand and an alkylidene group
contained within a cyclic structure, wherein the complex is capable
of catalyzing an olefin metathesis reaction with a latency period
of at least two minutes.
2. The organometallic complex of claim 1, capable of catalyzing an
olefin metathesis reaction with a latency period of at least five
minutes.
3. The organometallic complex of claim 1, wherein the olefin
metathesis reaction is ring closing metathesis.
4. The organometallic complex of claim 1, wherein the olefin
metathesis reaction is ring opening metathesis polymerization.
5. The organometallic complex of claim 2, wherein the olefin
metathesis reaction is ring closing metathesis.
6. The organometallic complex of claim 2, wherein the olefin
metathesis reaction is ring opening metathesis polymerization.
7. A complex having the structure of formula (I) 12wherein: .alpha.
and .beta. represent single bonds or unsaturated bonds, with the
proviso that .alpha. and .beta. cannot both be unsaturated bonds; M
is a Group 8 transition metal; R.sup.1 and R.sup.2 are
independently selected from hydrogen, hydrocarbyl, substituted
hydrocarbyl, heteroatom-containing hydrocarbyl, substituted
heteroatom-containing hydrocarbyl, and functional groups; Q is an
organic diradical; X.sup.1 and X.sup.2 are anionic ligands, and may
be the same or different; L.sup.1 is a neutral electron donor
ligand, and p is zero or 1; when .alpha. is a single bond, L.sup.2
is selected from NR.sup.7R.sup.8, PR.sup.7R.sup.8,
N.dbd.CR.sup.7R.sup.8, and R.sup.7C.dbd.NR.sup.8, where R.sup.7 and
R.sup.8 are independently selected from substituted and/or
heteroatom-containing C.sup.1-C.sub.20 alkyl, C.sub.2-C.sub.20
alkenyl, C.sub.2-C.sub.20 alkynyl, and C.sub.5-C.sub.24 aryl, or
R.sup.7 and R.sup.8 can be taken together to form a heterocyclic
ring; when .alpha. is an unsaturated bond, L.sup.2 is selected from
NR.sup.7 and PR.sup.7, where R.sup.7 is as defined previously, or
L.sup.2 and Z represent adjacent atoms in an aromatic ring; Y and Z
are linkages independently selected from hydrocarbylene,
substituted hydrocarbylene, heteroatom-containing hydrocarbylene,
substituted heteroatom-containing hydrocarbylene, --O--, --S--,
--NR.sup.9--, and --PR.sup.9--, wherein R.sup.9 is selected from
hydrocarbyl, substituted hydrocarbyl, heteroatom-containing
hydrocarbyl, and substituted heteroatom-containing hydrocarbyl, and
further wherein Y and Z may represent adjacent atoms in an aromatic
ring; m is zero or 1; and n is zero or 1, as well as isomers
thereof.
8. A complex having the structure of formula (II) 13wherein: .beta.
represent a single bond or an unsaturated bond; M is a Group 8
transition metal; R.sup.1 and R.sup.2 are independently selected
from hydrogen, hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, substituted
heteroatom-containing hydrocarbyl, and functional groups; Q is an
organic diradical; X.sup.1 and X.sup.2 are anionic ligands, and may
be the same or different; L.sup.1 is a neutral electron donor
ligand, and p is zero or 1; R.sup.7 and R.sup.8 are independently
selected from substituted and/or heteroatom-containing
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, and C.sub.5-C.sub.24 aryl, or R.sup.7 and R.sup.8 can be
taken together to form a heterocyclic ring; and Y and Z are
linkages independently selected from hydrocarbylene, substituted
hydrocarbylene, heteroatom-containing hydrocarbylene, substituted
heteroatom-containing hydrocarbylene, --O--, --S--, --NR.sup.9--,
and --PR.sup.9--, wherein R.sup.9 is selected from hydrocarbyl,
substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and
substituted heteroatom-containing hydrocarbyl, and further wherein
Y and Z may represent adjacent atoms in an aromatic ring, as well
as isomers thereof.
9. The complex of claim 8, wherein R.sup.7 and R.sup.8 are
C.sub.1-C.sub.12 alkyl or C.sub.5-C.sub.12 aryl, and Y is a
substituted or unsubstituted methylene or ethylene linkage.
10. A complex having the structure of formula (III) 14wherein:
.beta. represent a single bond or an unsaturated bond; M is a Group
8 transition metal; R.sup.1 and R.sup.2 are independently selected
from hydrogen, hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, substituted
heteroatom-containing hydrocarbyl, and functional groups; Q is an
organic diradical; X.sup.1 and X.sup.2 are anionic ligands, and may
be the same or different; L.sup.1 is a neutral electron donor
ligand, and p is zero or 1; R.sup.7 and R.sup.8 are independently
selected from substituted and/or heteroatom-containing
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, and C.sub.5-C.sub.24 aryl, or R.sup.7 and R.sup.8 can be
taken together to form a heterocyclic ring; and Y and Z are
linkages independently selected from hydrocarbylene, substituted
hydrocarbylene, heteroatom-containing hydrocarbylene, substituted
heteroatom-containing hydrocarbylene, --O--, --S--, --NR.sup.9--,
and --PR.sup.9--, wherein R.sup.9 is selected from hydrocarbyl,
substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and
substituted heteroatom-containing hydrocarbyl, and further wherein
Y and Z may represent adjacent atoms in an aromatic ring, as well
as isomers thereof.
11. The complex of claim 10, wherein R.sup.7 and R.sup.8 are
C.sub.1-C.sub.12 alkyl or C.sub.5-C.sub.12 aryl, and Y is a
substituted or unsubstituted methylene or ethylene linkage.
12. The complex of claim 11, wherein R.sup.7 and R.sup.8 are phenyl
and Y is ethylene.
13. A complex having the structure of formula (IV) 15wherein: M is
a Group 8 transition metal; R.sup.1 and R.sup.2 are independently
selected from hydrogen, hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, substituted
heteroatom-containing hydrocarbyl, and functional groups; Q is an
organic diradical; X.sup.1 and X.sup.2 are anionic ligands, and may
be the same or different; L.sup.1 is a neutral electron donor
ligand, and p is zero or 1; and Y is a linkage selected from
hydrocarbylene, substituted hydrocarbylene, heteroatom-containing
hydrocarbylene, substituted heteroatom-containing hydrocarbylene,
--O--, --S--, --NR.sup.9--, and --PR.sup.9--, wherein R.sup.9 is
selected from hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, and substituted
heteroatom-containing hydrocarbyl, as well as isomers thereof.
14. A complex having the structure of formula (V) 16wherein: M is a
Group 8 transition metal; R.sup.1 and R.sup.2 are independently
selected from hydrogen, hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, substituted
heteroatom-containing hydrocarbyl, and functional groups; Q is an
organic diradical; X.sup.1 and X.sup.2 are anionic ligands, and may
be the same or different; L.sup.1 is a neutral electron donor
ligand, and p is zero or 1; and R.sup.7 is selected from
substituted and/or heteroatom-containing C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl, and
C.sub.5-C.sub.24 aryl; and Y and Z are linkages independently
selected from hydrocarbylene, substituted hydrocarbylene,
heteroatom-containing hydrocarbylene, substituted
heteroatom-containing hydrocarbylene, --O--, --S--, --NR.sup.9--,
and --PR.sup.9--, wherein R.sup.9 is selected from hydrocarbyl,
substituted hydrocarbyl, heteroatom-containing hydrocarbyl, and
substituted heteroatom-containing hydrocarbyl, as well as isomers
thereof.
15. A method for catalyzing an olefin metathesis reaction,
comprising contacting an olefinic reactant with the catalytic
complex of any one of claims 1, 7, 8, 9, 10, 11, 12, 13, or 14
under reaction conditions selected to enable olefin metathesis.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C.
.sctn.119(e)(1) to Provisional U.S. Patent Applications Ser. No.
60/557,742, filed Mar. 29, 2004, and Ser. No. 60/604,158, filed
Aug. 23, 2004. The disclosures of the aforementioned provisional
patent applications are incorporated by reference herein.
TECHNICAL FIELD
[0002] This invention relates generally to olefin metathesis
catalysts, and more particularly pertains to new Group 8 transition
metal complexes that are useful as latent olefin metathesis
catalysts. The invention has utility in the fields of catalysis,
organic synthesis, and organometallic chemistry.
BACKGROUND OF THE INVENTION
[0003] Olefin metathesis catalysis is a powerful technology, which
in recent years has received tremendous attention as a versatile
method for the formation of carbon-carbon bonds and has numerous
applications in organic synthesis and polymer chemistry (R. H.
Grubbs, Handbook of Metathesis, Vol. 2 and 3; Wiley V C H,
Weinheim, 2003). The family of olefin metathesis reactions includes
ring-closing metathesis (RCM), cross metathesis (CM), ring-opening
metathesis polymerization (ROMP), and acyclic diene metathesis
polymerization (ADMET). The success of olefin metathesis stems from
the development of several well-defined transition metal complexes,
such as the Schrock molybdenum catalysts and the Grubbs ruthenium
and osmium catalysts (see, e.g., Schrock (1999) Tetrahedron 55,
8141-8153; Schrock (1990) Acc. Chem. Res. 23, 158-165; Grubbs et
al. (1998) Tetrahedron 54, 4413-4450; Trnka et al. (2001) Acc.
Chem. Res. 34, 18-29; Grubbs, Handbook of Metathesis, Vol. 1; Wiley
V C H, Weinheim, 2003). Following the discovery of these complexes,
a significant amount of olefin metathesis research has focused on
tuning the ruthenium and osmium carbene catalysts in order to
increase their activity, selectivity, and/or stability. The most
common strategy has involved the replacement of mono-dentate
ligands with other mono-dentate ligands to provide the catalytic
complexes with new and useful properties.
[0004] The original breakthrough ruthenium catalysts were primarily
bisphosphine complexes of the general formula
(PR.sub.3).sub.2(X).sub.2M=- CHR' wherein M is ruthenium (Ru) or
osmium (Os), X represents a halogen (e.g., Cl, Br, or I), R
represents an alkyl, cycloalkyl, or aryl group (e.g., butyl,
cyclohexyl, or phenyl), and R' represents an alkyl, alkenyl, or
aryl group (e.g., methyl, CH.dbd.C(CH.sub.3).sub.2, phenyl, etc.)
(see Nguyen et al. (1992) J. Am. Chem. Soc. 1992, 114, 3974-3975;
Schwab et al. (1995) Angew. Chem., Int. Ed. 34, 2039-2041; Schwab
et al. (1996) J. Am. Chem. Soc. 118, 100-110). Examples of these
types of catalysts are described in U.S. Pat. Nos. 5,312,940,
5,969,170 and 6,111,121 to Grubbs et al. While such complexes are
capable of catalyzing a considerable number of olefin metathesis
transformations, these bisphosphine complexes can exhibit lower
activity than desired and, under certain conditions, can have
limited lifetimes.
[0005] More recent developments in the field have led to greatly
increased activity and stability by replacing one of the phosphine
ligands with a bulky N-heterocyclic carbene (NHC) ligand (Scholl et
al. (1999) Organic Letters 1, 953-956) to give complexes of the
general formula (L)(PR.sub.3)(X).sub.2Ru.dbd.CHR', wherein L
represents an NHC ligand such as 1,3-dimesitylimidazole-2-ylidene
(IMes) and 1,3-dimesityl-4,5-dihydroimidazol-2-ylidene (sIMes), X
represents a halogen (e.g., Cl, Br, or I), R represents an alkyl,
cycloalkyl, or aryl group (e.g., butyl, cyclohexyl, or phenyl), and
R' represents an alkyl, alkenyl, or aryl group (e.g., methyl,
CH.dbd.C(CH.sub.3).sub.2, phenyl, etc.). Representative structures
include complex A (ibid.), complex B (Garber et al. (2000) J. Am.
Chem. Soc. 122, 8168-8179), and complex C (Sanford et al. (2001)
Organometallics 20, 5314-5318; Love et al. (2002) Angew. Chem.,
Int. Ed. 41, 4035-4037): 1
[0006] Unlike prior bisphosphine complexes, the various
imidazolylidine catalysts effect the efficient formation of
trisubstituted and tetrasubstituted olefins through catalytic
metathesis. Examples of these types of catalysts are described in
PCT publications WO 99/51344 and WO 00/71554. Further examples of
the synthesis and reactivity of some of these active ruthenium
complexes are reported by Furstner et al. (2001) Chem. Eur. J. 7,
No. 15, 3236-3253; Blackwell et al. (2000) J. Am. Chem. Soc. 122,
58-71; Chatterjee et al. (2000) J. Am. Chem. Soc. 122, 3783-3784;
Chatterjee et al. (2000) Angew. Chem. Int. Ed. 41, 3171-3174;
Chatterjee et al. (2003) J. Am. Chem. Soc. 125, 11360-11370.
Further tuning of these catalysts led to even higher activity by
using bulkier imidazolylidine ligands such as
1,3-bis(2,6-diisopropylphenyl)-4,5-dihydr- oimidazol-2-ylidenes
(Dinger et al. (2002) Adv. Synth. Catal. 344, 671-677) or electron
deficient phosphine ligands such as fluorinated aryl phosphines
(Love et al. (2003) J. Am. Chem. Soc. 125, 10103-10109).
[0007] Another example of ligand substitution that has led to
enhanced catalyst activity is the replacement of the phosphine
ligand in the (L)(PR.sub.3)(X).sub.2M=CHR' complexes with one or
two pyridine-type ligands to give compounds of the general formula
(L)(L').sub.n(X).sub.2M=- CHR' wherein n=1 or 2, L represents an
imidazolylidine ligand, L' represents a pyridine (Py) or
substituted pyridine ligand, X represents a halogen (e.g., Cl, Br,
or I), and R' represents an alkyl, alkenyl, or aryl group (e.g.,
methyl, CH.dbd.C(CH.sub.3).sub.2, phenyl, etc.). These pyridine
complexes are extremely fast-initiating and catalyze living
ring-opening metathesis polymerizations (Choi et al. (2003) Chem.
Int. Ed. 42, 1743-1746) as well as highly challenging processes
such as olefin cross metathesis with acrylonitrile (Love et al.
(2002) Angew. Chem. Int. Ed. 41, 4035-4037).
[0008] Yet another example of mono-dentate ligand substitution is
the replacement of the halogen ligands with aryl-oxo ligands, which
in one example has led to a catalyst with enhanced activity:
(L)(L').sub.n(RO).sub.2Ru.dbd.CHR' wherein n=1, L represents an
imidazolylidine ligand, L' represents a pyridine ligand, R
represents a fluorinated aryl group, and R' represents an alkyl,
alkenyl, or aryl group (Conrad et al. (2003) Organometallics 22,
3634-3636).
[0009] A different strategy to tune olefin metathesis catalysts
involves linking two of the ligands that are attached to the metal
center. Of particular interest are the chelating carbene species
reported by Hoveyda and others (Gaber et al. (2000) J. Am. Chem.
Soc. 122, 8168-8179; Kingsbury et al. (1999) J. Am. Chem. Soc. 121,
791-799; Harrity et al. (1997) J. Am. Chem. Soc. 119, 1488-1489;
Harrity et al. (1998) J. Am. Chem. Soc. 120, 2343-2351). These
catalysts are exceptionally stable and can be purified by column
chromatography in air. Representative such catalysts, designated
Catalyst PR-1 and PR-2, are illustrated in FIG. 1. Catalyst PR-2
combines excellent stability and enhanced activity, and actively
promotes the cross-metathesis of acrylonitrile and terminal olefins
in moderate to excellent yields.
[0010] While most of these efforts have focused on increasing the
activity and initiation rate of the ruthenium carbene metathesis
catalysts, there remains a need for highly active catalysts that
initiate more slowly (i.e., are more latent). This can be a
particularly beneficial feature when performing metathesis
polymerizations, which, in practice, typically require a
significant period of time (the "work-time") within which to mix,
handle, and process the catalyst/resin mixture before it gels or
solidifies. For one-part catalyst systems, such as the metal
carbene olefin metathesis catalysts, latency is generally achieved
through temperature variation. Either the catalyst/resin mixture
can be handled at a low enough temperature to sufficiently inhibit
polymerization or the catalyst must be designed to be
heat-activated to allow sufficient work-time at ambient
temperatures.
[0011] One example of a thermally activated, latent metathesis
polymerization catalyst system utilizing slower initiating
ruthenium and osmium vinylidene complexes was described in U.S.
Pat. No. 6,107,420. However, only a modest degree of control of the
latency can be achieved by varying the identity of the substituent
groups of the vinylidene ligand and such vinylidene complexes are
often not efficient metathesis catalysts for unstrained olefins.
Another example of a latent olefin metathesis catalyst that
contains a chelating carbene ligand is the 2-pyridylethanyl
ruthenium carbene complex (PR.sub.3)(Cl).sub.2Ru(CH(CH.s-
ub.2).sub.2--C,N-2-C.sub.5H.sub.4N) by reacting a
(PR.sub.3).sub.2(Cl).sub- .2Ru.dbd.CHR' complex with
2-(3-butenyl)pyridine developed by van der Schaaf (van der Schaaf
et al. (2000) J. Organometallic Chemistry 606, 65-74). These types
of catalysts are also described in U.S. Pat. No. 6,306,987.
Although these catalysts do initiate more slowly than their
bis-phosphine counterparts, they lack the high activity of the NHC
catalyst systems. A further type of latent olefin metathesis
catalysts is described by van der Schaaf in U.S. Pat. No.
6,077,805. These latter catalysts are hexacoordinate ruthenium or
osmium complexes wherein two of the six ligands are preferably
pyridine ligands.
[0012] In trying to develop new examples of latent, high-activity
catalysts containing NHC ligands, the teaching in the prior art
provides no clear direction. U.S. Pat. No. 6,077,805 teaches that
hexacoordinate phosphine-ligated complexes of the general structure
(PR.sub.3)(X).sub.2(L).sub.2M=CHR', wherein the L ligands are
pyridines or substituted pyridines or together are chelating
bipyridines, are latent metathesis catalysts. Data presented in
U.S. Patent Application Publication Number 2002/0177710 confirm the
latency of such catalysts but also show that, in contrast, related
hexacoordinate NHC-ligated complexes of the general structure
(NHC)(X).sub.2(L).sub.2M=CHR' are not latent catalysts but, in
fact, are actually some of the most rapidly initiating catalysts of
this type ever observed (e.g., cf. Choi et al. (2003) Angew. Chem.
Int. Ed. 42, 1743-1746 and Love et al. (2002 Angew. Chem. Int. Ed.
41, 4035-4037). U.S. Pat. No. 6,306,987 teaches that
phosphine-ligated bridging carbene complexes of the general
structure D are latent metathesis catalysts, whereas similar
NHC-ligated complexes of the general structure E are not (e.g.,
Courchay et al. (2003) Macromolecules 36, 8231-8239). These
observations suggest that it is difficult to achieve latency with
the high-activity catalysts comprising NHC ligands. 2
[0013] Accordingly, despite advances in the art, there is a
continuing need for olefin metathesis catalysts that initiate
slowly while maintaining the high activity associated with
NHC-based catalysts.
SUMMARY OF THE INVENTION
[0014] The present invention relates to novel high-activity but
latent olefin metathesis catalysts that comprise an NHC ligand and
a chelating carbene ligand. By careful choice of the chelating
carbene ligand, catalysts are provided that have a latency period
on the order of minutes to hours, or even longer. It has also been
surprisingly discovered that the initiation rate of some of these
catalysts can be substantially varied via simple isomerization of
the complexes and that the reactivity can be tuned over a wide
range by controlling the ratio of the different isomers. The
catalysts are particularly useful in the RCM of acyclic olefins and
the ROMP of cyclic olefins.
[0015] The present catalytic complexes generally have the structure
of formula (I) 3
[0016] wherein:
[0017] the bonds indicated as dashed lines and designated as
.alpha. and .beta. represent single bonds or unsaturated (e.g.,
double) bonds, with the proviso that .alpha. and .beta. cannot both
be unsaturated bonds;
[0018] M is a Group 8 transition metal, generally ruthenium (Ru) or
osmium (Os);
[0019] R.sup.1 and R.sup.2 are independently selected from
hydrogen, hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, substituted
heteroatom-containing hydrocarbyl, and functional groups;
[0020] Q is an organic diradical, i.e., a hydrocarbylene,
substituted hydrocarbylene, heteroatom-containing hydrocarbylene,
or substituted heteroatom-containing hydrocarbylene linker, and
further wherein two or more substituents on adjacent atoms within Q
may be linked to form an additional cyclic group;
[0021] X.sup.1 and X.sup.2 are anionic ligands, and may be the same
or different;
[0022] L.sup.1 is a neutral electron donor ligand, and p is zero or
1;
[0023] when .alpha. is a single bond, L.sup.2 is selected from
NR.sup.7R.sup.8, PR.sup.7R.sup.8, N.dbd.CR.sup.7R.sup.8, and
R.sup.7C.dbd.NR.sup.8, where R.sup.7 and R.sup.8 are independently
selected from substituted and/or heteroatom-containing
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, and C.sub.5-C.sub.24 aryl, or R.sup.7 and R.sup.8 can be
taken together to form a heterocyclic ring;
[0024] when .alpha. is an unsaturated bond, e.g., a double bond,
L.sup.2 is selected from NR.sup.7 and PR.sup.7, where R.sup.7 is as
defined previously;
[0025] Y and Z are linkages independently selected from
hydrocarbylene, substituted hydrocarbylene, heteroatom-containing
hydrocarbylene, substituted heteroatom-containing hydrocarbylene,
--O--, --S--, --NR.sup.9--, and --PR.sup.9--, wherein R.sup.9 is
selected from hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, and substituted
heteroatom-containing hydrocarbyl, and further wherein Y and Z, or
L.sup.2 and Z, may represent adjacent atoms in an aromatic
ring;
[0026] m is zero or 1; and
[0027] n is zero or 1,
[0028] and also include isomers thereof.
[0029] In another embodiment, a method for carrying out an olefin
metathesis reaction is provided using the aforementioned complexes
as reaction catalysts.
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] FIG. 1 provides the molecular structures of two metathesis
catalysts of the prior art, indicated as Pr-1 and Pr-2.
[0031] FIG. 2 provides the molecular structures of two
representative catalytic complexes of the invention, indicated as
Catalysts 2a and 2b.
[0032] FIG. 3 depicts an ORTEP drawing of the X-ray crystal
structure of Catalyst 2a.
[0033] FIG. 4 depicts an ORTEP drawing of the X-ray crystal
structure of Catalyst 2b.
[0034] FIG. 5 provides the molecular structures of two
representative catalytic complexes of the invention, indicated as
Catalysts 4 and 5.
[0035] FIG. 6 provides the molecular structures of additional
representative catalytic complexes of the invention.
[0036] FIG. 7 schematically depicts a method for synthesizing
representative catalytic complexes 2a, 4 and 5 of the
invention.
[0037] FIG. 8 schematically depicts a method for synthesizing
representative catalytic complexes 2b of the invention.
[0038] FIG. 9 provides the molecular structure of additional
representative catalytic complexes of the invention.
[0039] FIG. 10 illustrates the percent of reactant converted versus
time for the RCM reaction of diethyldiallyl malonate using
catalysts 1, 2a, 2b and 12, as described in Example 15.
[0040] FIG. 11 illustrates the percent of reactant converted versus
time for the RCM reaction of diethyldiallyl malonate using
catalysts 2a, 4 and 5, as described in Example 16.
[0041] FIG. 12 illustrates the percent of reactant converted versus
time for the RCM reaction of diethyldiallyl malonate using
catalysts 2a, 7 and 8, as described in Example 17.
[0042] FIG. 13 illustrates the percent of reactant converted versus
time for the RCM reaction of diethyldiallyl malonate using
catalysts 7, 8, 9, 10, and 11, as also described in Example 17.
[0043] FIG. 14 provides the exotherms for the RCM reaction of
diethyldiallyl malonate to assess the activity of catalysts 6 and
8, as described in Example 18.
[0044] FIG. 15 provides the exotherms for the ROMP reaction
catalyzed by catalysts 2a and 2b, as described in Example 19.
[0045] FIG. 16 provides the exotherms for the ROMP reaction
catalyzed by catalysts 2a, 2b and 12, as also described in Example
19.
[0046] FIG. 17 provides the exotherms for the ROMP reactions
catalyzed using different mixtures of 2a and 2b, as described in
Example 20.
[0047] FIG. 18 provides the exotherms for the ROMP reaction
catalyzed by catalysts 2a, 7 and 8, as described in Example 21.
DETAILED DESCRIPTION OF THE INVENTION
[0048] It is to be understood that unless otherwise indicated this
invention is not limited to specific reactants, reaction
conditions, or the like, as such may vary. It is also to be
understood that the terminology used herein is for the purpose of
describing particular embodiments only and is not intended to be
limiting.
[0049] As used in the specification and the appended claims, the
singular forms "a," "tan" and "the" include plural referents unless
the context clearly dictates otherwise. Thus, for example,
reference to "a catalyst" or "a complex" encompasses a combination
or mixture of different catalysts or complexes as will as a single
catalyst or complex, reference to "a substituent" includes a single
substituent as well as two or more substituents that may or may not
be the same, and the like.
[0050] In this specification and in the claims that follow,
reference will be made to a number of terms, which shall be defined
to have the following meanings:
[0051] The phrase "having the formula" or "having the structure" is
not intended to be limiting and is used in the same way that the
term "comprising" is commonly used.
[0052] The term "alkyl" as used herein refers to a linear,
branched, or cyclic saturated hydrocarbon group typically although
not necessarily containing 1 to about 20 carbon atoms, preferably 1
to about 12 carbon atoms, such as methyl, ethyl, n-propyl,
isopropyl, n-butyl, isobutyl, t-butyl, octyl, decyl, and the like,
as well as cycloalkyl groups such as cyclopentyl, cyclohexyl and
the like. Generally, although again not necessarily, alkyl groups
herein contain 1 to about 12 carbon atoms. The term "lower alkyl"
intends an alkyl group of 1 to 6 carbon atoms, and the specific
term "cycloalkyl" intends a cyclic alkyl group, typically having 4
to 8, preferably 5 to 7, carbon atoms. The term "substituted alkyl"
refers to alkyl substituted with one or more substituent groups,
and the terms "heteroatom-containing alkyl" and "heteroalkyl" refer
to alkyl in which at least one carbon atom is replaced with a
heteroatom. If not otherwise indicated, the terms "alkyl" and
"lower alkyl" include linear, branched, cyclic, unsubstituted,
substituted, and/or heteroatom-containing alkyl and lower alkyl,
respectively.
[0053] The term "alkylene" as used herein refers to a difunctional
linear, branched, or cyclic alkyl group, where "alkyl" is as
defined above.
[0054] The term "alkenyl" as used herein refers to a linear,
branched, or cyclic hydrocarbon group of 2 to about 20 carbon atoms
containing at least one double bond, such as ethenyl, n-propenyl,
isopropenyl, n-butenyl, isobutenyl, octenyl, decenyl, tetradecenyl,
hexadecenyl, eicosenyl, tetracosenyl, and the like. Preferred
alkenyl groups herein contain 2 to about 12 carbon atoms. The term
"lower alkenyl" intends an alkenyl group of 2 to 6 carbon atoms,
and the specific term "cycloalkenyl" intends a cyclic alkenyl
group, preferably having 5 to 8 carbon atoms. The term "substituted
alkenyl" refers to alkenyl substituted with one or more substituent
groups, and the terms "heteroatom-containing alkenyl" and
"heteroalkenyl" refer to alkenyl in which at least one carbon atom
is replaced with a heteroatom. If not otherwise indicated, the
terms "alkenyl" and "lower alkenyl" include linear, branched,
cyclic, unsubstituted, substituted, and/or heteroatom-containing
alkenyl and lower alkenyl, respectively.
[0055] The term "alkenylene" as used herein refers to a
difunctional linear, branched, or cyclic alkenyl group, where
"alkenyl" is as defined above.
[0056] The term "alkynyl" as used herein refers to a linear or
branched hydrocarbon group of 2 to about 20 carbon atoms containing
at least one triple bond, such as ethynyl, n-propynyl, and the
like. Preferred alkynyl groups herein contain 2 to about 12 carbon
atoms. The term "lower alkynyl" intends an alkynyl group of 2 to 6
carbon atoms. The term "substituted alkynyl" refers to alkynyl
substituted with one or more substituent groups, and the terms
"heteroatom-containing alkynyl" and "heteroalkynyl" refer to
alkynyl in which at least one carbon atom is replaced with a
heteroatom. If not otherwise indicated, the terms "alkynyl" and
"lower alkynyl" include linear, branched, unsubstituted,
substituted, and/or heteroatom-containing alkynyl and lower
alkynyl, respectively.
[0057] The term "alkynylene" as used herein refers to a
difunctional alkynyl group, where "alkynyl" is as defined
above.
[0058] The term "alkoxy" as used herein intends an alkyl group
bound through a single, terminal ether linkage; that is, an
"alkoxy" group may be represented as --O-alkyl where alkyl is as
defined above. A "lower alkoxy" group intends an alkoxy group
containing 1 to 6 carbon atoms. Analogously, "alkenyloxy" and
"lower alkenyloxy" respectively refer to an alkenyl and lower
alkenyl group bound through a single, terminal ether linkage, and
"alkynyloxy" and "lower alkynyloxy" respectively refer to an
alkynyl and lower alkynyl group bound through a single, terminal
ether linkage.
[0059] The term "aryl," as used herein and unless otherwise
specified, refers to an aromatic substituent containing a single
aromatic ring or multiple aromatic rings that are fused together,
directly linked, or indirectly linked (such that the different
aromatic rings are bound to a common group such as a methylene or
ethylene moiety). Preferred aryl groups contain 5 to 24 carbon
atoms, and particularly preferred aryl groups contain 5 to 14
carbon atoms. Exemplary aryl groups contain one aromatic ring or
two fused or linked aromatic rings, e.g., phenyl, naphthyl,
biphenyl, diphenylether, diphenylamine, benzophenone, and the like.
"Substituted aryl" refers to an aryl moiety substituted with one or
more substituent groups, and the terms "heteroatom-containing aryl"
and "heteroaryl" refer to aryl substituent, in which at least one
carbon atom is replaced with a heteroatom, as will be described in
further detail infra.
[0060] The term "aryloxy" as used herein refers to an aryl group
bound through a single, terminal ether linkage, wherein "aryl" is
as defined above. An "aryloxy" group may be represented as --O-aryl
where aryl is as defined above. Preferred aryloxy groups contain 5
to 20 carbon atoms, and particularly preferred aryloxy groups
contain 5 to 14 carbon atoms. Examples of aryloxy groups include,
without limitation, phenoxy, o-halo-phenoxy, m-halo-phenoxy,
p-halo-phenoxy, o-methoxy-phenoxy, m-methoxy-phenoxy,
p-methoxy-phenoxy, 2,4-dimethoxy-phenoxy, 3,4,5-trimethoxy-phenoxy,
and the like.
[0061] The term "alkaryl" refers to an aryl group with an alkyl
substituent, and the term "aralkyl" refers to an alkyl group with
an aryl substituent, wherein "aryl" and "alkyl" are as defined
above. Preferred alkaryl and aralkyl groups contain 6 to 24 carbon
atoms, and particularly preferred alkaryl and aralkyl groups
contain 6 to 16 carbon atoms. Alkaryl groups include, for example,
p-methylphenyl, 2,4-dimethylphenyl, p-cyclohexylphenyl,
2,7-dimethylnaphthyl, 7-cyclooctylnaphthyl,
3-ethyl-cyclopenta-1,4-diene, and the like. Examples of aralkyl
groups include, without limitation, benzyl, 2-phenyl-ethyl,
3-phenyl-propyl, 4-phenyl-butyl, 5-phenyl-pentyl,
4-phenylcyclohexyl, 4-benzylcyclohexyl, 4-phenylcyclohexylmethyl,
4-benzylcyclohexylmethyl, and the like. The terms "alkaryloxy" and
"aralkyloxy" refer to substituents of the formula --OR wherein R is
alkaryl or aralkyl, respectively, as just defined.
[0062] The term "acyl" refers to substituents having the formula
--(CO)-alkyl, --(CO)-aryl, or --(CO)-aralkyl, and the term
"acyloxy" refers to substituents having the formula --O(CO)-alkyl,
--O(CO)-aryl, or --O(CO)-aralkyl, wherein "alkyl," "aryl, and
"aralkyl" are as defined above.
[0063] The term "cyclic" refers to alicyclic or aromatic
substituents that may or may not be substituted and/or heteroatom
containing, and that may be monocyclic, bicyclic, or polycyclic.
The term "alicyclic" is used in the conventional sense to refer to
an aliphatic cyclic moiety, as opposed to an aromatic cyclic
moiety, and may be monocyclic, bicyclic, or polycyclic.
[0064] The terms "halo" and "halogen" are used in the conventional
sense to refer to a chloro, bromo, and fluoro or iodo
substituent.
[0065] "Hydrocarbyl" refers to univalent hydrocarbyl radicals
containing 1 to about 30 carbon atoms, preferably 1 to about 24
carbon atoms, most preferably 1 to about 12 carbon atoms, including
linear, branched, cyclic, saturated, and unsaturated species, such
as alkyl groups, alkenyl groups, aryl groups, and the like. The
term "lower hydrocarbyl" intends a hydrocarbyl group of 1 to 6
carbon atoms, preferably 1 to 4 carbon atoms, and the term
"hydrocarbylene" intends a divalent hydrocarbyl moiety containing 1
to about 30 carbon atoms, preferably 1 to about 24 carbon atoms,
most preferably 1 to about 12 carbon atoms, including linear,
branched, cyclic, saturated and unsaturated species. The term
"lower hydrocarbylene" intends a hydrocarbylene group of 1 to 6
carbon atoms. "Substituted hydrocarbyl" refers to hydrocarbyl
substituted with one or more substituent groups, and the terms
"heteroatom-containing hydrocarbyl" and "heterohydrocarbyl" refer
to hydrocarbyl in which at least one carbon atom is replaced with a
heteroatom. Similarly, "substituted hydrocarbylene" refers to
hydrocarbylene substituted with one or more substituent groups, and
the terms "heteroatom-containing hydrocarbylene" and
heterohydrocarbylene" refer to hydrocarbylene in which at least one
carbon atom is replaced with a heteroatom. Unless otherwise
indicated, the term "hydrocarbyl" and "hydrocarbylene" are to be
interpreted as including substituted and/or heteroatom-containing
hydrocarbyl and hydrocarbylene moieties, respectively.
[0066] The term "heteroatom-containing" as in a
"heteroatom-containing hydrocarbyl group" refers to a hydrocarbon
molecule or a hydrocarbyl molecular fragment in which one or more
carbon atoms is replaced with an atom other than carbon, e.g.,
nitrogen, oxygen, sulfur, phosphorus or silicon, typically
nitrogen, oxygen or sulfur. Similarly, the term "heteroalkyl"
refers to an alkyl substituent that is heteroatom-containing, the
term "heterocyclic" refers to a cyclic substituent that is
heteroatom-containing, the terms "heteroaryl" and heteroaromatic"
respectively refer to "aryl" and "aromatic" substituents that are
heteroatom-containing, and the like. It should be noted that a
"heterocyclic" group or compound may or may not be aromatic, and
further that "heterocycles" may be monocyclic, bicyclic, or
polycyclic as described above with respect to the term "aryl."
[0067] By "substituted" as in "substituted hydrocarbyl,"
"substituted alkyl," "substituted aryl," and the like, as alluded
to in some of the aforementioned definitions, is meant that in the
hydrocarbyl, alkyl, aryl, or other moiety, at least one hydrogen
atom bound to a carbon (or other) atom is replaced with one or more
non-hydrogen substituents. Examples of such substituents include,
without limitation: functional groups referred to herein as "Fn,"
such as halo, hydroxyl, sulfhydryl, C.sub.1-C.sub.20 alkoxy,
C.sub.2-C.sub.20 alkenyloxy, C.sub.2-C.sub.20 alkynyloxy,
C.sub.5-C.sub.24 aryloxy, C.sub.6-C.sub.24 aralkyloxy,
C.sub.6-C.sub.24 alkaryloxy, acyl (including C.sub.2-C.sub.20
alkylcarbonyl (--CO-alkyl) and C.sub.6-C.sub.24 arylcarbonyl
(--CO-aryl)), acyloxy (--O-acyl, including C.sub.2-C.sub.20
alkylcarbonyloxy (--O--CO-alkyl) and C.sub.6-C.sub.24
arylcarbonyloxy (--O--CO-aryl)), C.sub.2-C.sub.20 alkoxycarbonyl
(--(CO)--O-alkyl), C.sub.6-C.sub.24 aryloxycarbonyl
(--(CO)--O-aryl), halocarbonyl (--CO)--X where X is halo),
C.sub.2-C.sub.20 alkylcarbonato (--O--(CO)--O-alkyl),
C.sub.6-C.sub.24 arylcarbonato (--O--(CO)--O-aryl), carboxy
(--COOH), carboxylato (--COO.sup.-), carbamoyl (--(CO)--NH.sub.2),
mono-(C.sub.1-C.sub.20 alkyl)-substituted carbamoyl
(--(CO)--NH(C.sub.1-C.sub.20 alkyl)), di-(C.sub.1-C.sub.20
alkyl)-substituted carbamoyl (--(CO)--N(C.sub.1-C.sub.20
alkyl).sub.2), mono-(C.sub.5-C.sub.24 aryl)-substituted carbamoyl
(--(CO)--NH-aryl), di-(C.sub.5-C.sub.24 aryl)-substituted carbamoyl
(--(CO)--N(C.sub.5-C.sub- .24 aryl).sub.2), di-N-(C.sub.1-C.sub.20
alkyl),N--(C.sub.5-C.sub.24 aryl)-substituted carbamoyl,
thiocarbamoyl (--(CS)--NH.sub.2), mono-(C.sub.1-C.sub.20
alkyl)-substituted thiocarbamoyl (--(CO)--NH(C.sub.1-C.sub.20
alkyl)), di-(C.sub.1-C.sub.20 alkyl)-substituted thiocarbamoyl
(--(CO)--N(C.sub.1-C.sub.20 alkyl).sub.2), mono-(C.sub.5-C.sub.24
aryl)-substituted thiocarbamoyl (--(CO)--NH-aryl),
di-(C.sub.5-C.sub.24 aryl)-substituted thiocarbamoyl
(--(CO)--N(C.sub.5-C.sub.24 aryl).sub.2), di-N--(C.sub.1-C.sub.20
alkyl),N--(C.sub.5-C.sub.24 aryl)-substituted thiocarbamoyl,
carbamido (--NH--(CO)--NH.sub.2), cyano(--C.ident.N), cyanato
(--O--C.ident.N), thiocyanato (--S--C.ident.N), isocyano
(--N+.ident.C.sup.-), formyl (--(CO)--H), thioformyl (--(CS)--H),
amino (--NH.sub.2), mono-(C.sub.1-C.sub.20 alkyl)-substituted
amino, di-(C.sub.1-C.sub.20 alkyl)-substituted amino,
mono-(C.sub.5-C.sub.24 aryl)-substituted amino,
di-(C.sub.5-C.sub.24 aryl)-substituted amino, C.sub.2-C.sub.20
alkylamido (--NH--(CO)-alkyl), C.sub.6-C.sub.24 arylamido
(--NH--(CO)-aryl), imino (--CR.dbd.NH where R=hydrogen,
C.sub.1-C.sub.20 alkyl, C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24
alkaryl, C.sub.6-C.sub.24 aralkyl, etc.), C.sub.2-C.sub.20
alkylimino (--CR.dbd.N(alkyl), where R=hydrogen, C.sub.1-C.sub.20
alkyl, C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl,
C.sub.6-C.sub.24 aralkyl, etc.), arylimino (--CR.dbd.N(aryl), where
R=hydrogen, C.sub.1-C.sub.20 alkyl, C.sub.5-C.sub.24 aryl,
C.sub.6-C.sub.24 alkaryl, C.sub.6-C.sub.24 aralkyl, etc.), nitro
(--NO.sub.2), nitroso (--NO), sulfo (--SO.sub.2--OH), sulfonato
(--SO.sub.2--O.sup.-), C.sub.1-C.sub.20 alkylsulfanyl (--S-alkyl;
also termed "alkylthio"), C.sub.5-C.sub.24 arylsulfanyl (--S-aryl;
also termed "arylthio"), C.sub.1-C.sub.20 alkyldithio
(--S--S-alkyl), C.sub.5-C.sub.24 aryldithio (--S--S-aryl),
C.sub.1-C.sub.20 alkylsulfinyl (--(SO)-alkyl), C.sub.5-C.sub.24
arylsulfinyl (--(SO)-aryl), C.sub.1-C.sub.20 alkylsulfonyl
(--SO.sub.2-alkyl), C.sub.5-C.sub.24 arylsulfonyl
(--SO.sub.2-aryl), boryl (--BH.sub.2), borono (--B(OH).sub.2),
boronato (--B(OR).sub.2 where R is alkyl or other hydrocarbyl),
phosphono (--P(O)(OH).sub.2), phosphonato (--P(O)(O.sup.-).sub.2),
phosphinato (--P(O)(O.sup.-)), phospho (--PO.sub.2), phosphino
(--PH.sub.2), silyl (--SiR.sub.3 wherein R is hydrogen or
hydrocarbyl), and silyloxy (--O-silyl), and the hydrocarbyl
moieties C.sub.1-C.sub.20 alkyl (preferably C.sub.1-C.sub.12 alkyl,
more preferably C.sub.1-C.sub.6 alkyl), C.sub.2-C.sub.20 alkenyl
(preferably C.sub.2-C.sub.12 alkenyl, more preferably
C.sub.2-C.sub.6 alkenyl), C.sub.2-C.sub.20 alkynyl (preferably
C.sub.2-C.sub.12 alkynyl, more preferably C.sub.2-C.sub.6 alkynyl),
C.sub.5-C.sub.24 aryl (preferably C.sub.5-C.sub.14 aryl),
C.sub.6-C.sub.24 alkaryl (preferably C.sub.6-C.sub.16 alkaryl), and
C.sub.6-C.sub.24 aralkyl (preferably C.sub.6-C.sub.16 aralkyl).
[0068] In addition, the aforementioned functional groups may, if a
particular group permits, be further substituted with one or more
additional functional groups or with one or more hydrocarbyl
moieties such as those specifically enumerated above. Analogously,
the above-mentioned hydrocarbyl moieties may be further substituted
with one or more functional groups or additional hydrocarbyl
moieties such as those specifically enumerated.
[0069] In the molecular structures herein, the use of bold and
dashed lines to denote particular conformation of groups follows
the IUPAC convention. A bond indicated by a broken line indicates
that the group in question is below the general plane of the
molecule as drawn, and a bond indicated by a bold line indicates
that the group at the position in question is above the general
plane of the molecule as drawn.
[0070] In one embodiment, then, the invention provides a Group 8
transition metal complex having the structure of formula (I) 4
[0071] wherein:
[0072] the bonds indicated as dashed lines and designated as
.alpha. and .beta. represent single bonds or unsaturated (e.g.,
double) bonds, with the proviso that .alpha. and .beta. cannot both
be unsaturated bonds;
[0073] M is a Group 8 transition metal;
[0074] R.sup.1 and R.sup.2 are independently selected from
hydrogen, hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, substituted
heteroatom-containing hydrocarbyl, and functional groups;
[0075] Q is an organic diradical, i.e., a hydrocarbylene,
substituted hydrocarbylene, heteroatom-containing hydrocarbylene,
or substituted heteroatom-containing hydrocarbylene linker, and
further wherein two or more substituents on adjacent atoms within Q
may be linked to form an additional cyclic group;
[0076] X.sup.1 and X.sup.2 are anionic ligands, and may be the same
or different;
[0077] L.sup.1 is a neutral electron donor ligand, and p is zero or
1;
[0078] when .alpha. is a single bond, L.sup.2 is selected from
NR.sup.7R.sup.8, PR.sup.7R.sup.8, N.dbd.CR.sup.7R.sup.8, and
R.sup.7C.dbd.NR.sup.8, where R.sup.7 and R.sup.8 are independently
selected from substituted and/or heteroatom-containing
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, and C.sub.5-C.sub.24 aryl, or R.sup.7 and R.sup.8 can be
taken together to form a heterocyclic ring;
[0079] when .alpha. is an unsaturated bond, e.g., a double bond,
L.sup.2 is selected from NR.sup.7 and PR.sup.7, where R.sup.7 is as
defined previously;
[0080] Y and Z are linkages independently selected from
hydrocarbylene, substituted hydrocarbylene, heteroatom-containing
hydrocarbylene, substituted heteroatom-containing hydrocarbylene,
--O--, --S--, --NR.sup.9--, and --PR.sup.9--, wherein R.sup.9 is
selected from hydrocarbyl, substituted hydrocarbyl,
heteroatom-containing hydrocarbyl, and substituted
heteroatom-containing hydrocarbyl, and further wherein Y and Z, or
L.sup.2 and Z, may represent adjacent atoms in an aromatic
ring;
[0081] m is zero or 1; and
[0082] n is zero or 1,
[0083] as well as isomers thereof.
[0084] More particularly:
[0085] The metal center designated as M is a Group 8 transition
metal, preferably ruthenium or osmium. In a particularly preferred
embodiment, M is ruthenium.
[0086] R.sup.1 and R.sup.2 are independently selected from
hydrogen, hydrocarbyl (e.g., C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl,
C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl, C.sub.6-C.sub.24
aralkyl, etc.), substituted hydrocarbyl (e.g., substituted
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl,
C.sub.6-C.sub.24 aralkyl, etc.), heteroatom-containing hydrocarbyl
(e.g., heteroatom-containing C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl,
C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl, C.sub.6-C.sub.24
aralkyl, etc.), substituted heteroatom-containing hydrocarbyl
(e.g., substituted heteroatom-containing C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl,
C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl, C.sub.6-C.sub.24
aralkyl, etc.), and functional groups. When R.sup.1 and R.sup.2 are
aromatic, they are typically although not necessarily composed of
one or two aromatic rings, which may or may not be substituted,
e.g., R.sup.1 and R.sup.2 may be phenyl, substituted phenyl,
biphenyl, substituted biphenyl, or the like. In one preferred
embodiment, R.sup.1 and R.sup.2 are the same and are each
unsubstituted phenyl or phenyl substituted with up to three
substituents selected from C.sub.1-C.sub.20 alkyl, substituted
C.sub.1-C.sub.20 alkyl, C.sub.1-C.sub.20 heteroalkyl, substituted
C.sub.1-C.sub.20 heteroalkyl, C.sub.5-C.sub.24 aryl, substituted
C.sub.5-C.sub.24 aryl, C.sub.5-C.sub.24 heteroaryl,
C.sub.6-C.sub.24 aralkyl, C.sub.6-C.sub.24 alkaryl, and halide.
Preferably, any substituents present are hydrogen, C.sub.1-C.sub.12
alkyl, C.sub.1-C.sub.12 alkoxy, C.sub.5-C.sub.14 aryl, substituted
C.sub.5-C.sub.14 aryl, or halide. More preferably, R.sup.1 and
R.sup.2 are mesityl.
[0087] In another preferred embodiment, R.sup.1 and R.sup.2 are
independently selected from hydrogen, C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl,
C.sub.5-C.sub.24 substituted aryl, C.sub.1-C.sub.20 functionalized
alkyl, C.sub.2-C.sub.20 functionalized alkenyl, C.sub.2-C.sub.20
functionalized alkynyl, or C.sub.5-C.sub.24 functionalized
substituted aryl where the functional group(s) ("Fn") may
independently be one or more or the following:
[0088] C.sub.1-C.sub.20 alkoxy, C.sub.5-C.sub.24 aryloxy, halo,
carboxy (--COOH), acyl (including C.sub.2-C.sub.20 alkylcarbonyl
(--CO-alkyl) and C.sub.6-C.sub.24 arylcarbonyl (--CO-aryl)), formyl
(--(CO)--H), nitro (--NO.sub.2), cyano(--C.ident.N), isocyano
(--N.sup.+.ident.C.sup.-), hydroxyl, acyloxy (--O-acyl, including
C.sub.2-C.sub.20 alkylcarbonyloxy (--O--CO-alkyl) and
C.sub.6-C.sub.24 arylcarbonyloxy (--O--CO-aryl)), C.sub.2-C.sub.20
alkoxycarbonyl (--(CO)--O-alkyl), C.sub.6-C.sub.24 aryloxycarbonyl
(--(CO)--O-aryl), C.sub.1-C.sub.20 alkoxy-substituted
C.sub.1-C.sub.20 alkyl, C.sub.1-C.sub.20 alkoxy-substituted
C.sub.5-C.sub.24 aryl, C.sub.5-C.sub.24 aryloxy-substituted
C.sub.1-C.sub.20 alkyl, C.sub.5-C.sub.24 aryloxy-substituted
C.sub.5-C.sub.24 aryl, amino (--NH.sub.2), imino (--CR.dbd.NH where
R=hydrogen, C.sub.1-C.sub.20 alkyl, C.sub.5-C.sub.24 aryl,
C.sub.6-C.sub.24 alkaryl, C.sub.6-C.sub.24 aralkyl, etc.),
C.sub.2-C.sub.20 alkylamido (--NH--(CO)-alkyl), C.sub.6-C.sub.24
arylamido (--NH--(CO)-aryl), C.sub.1-C.sub.20 alkylsulfanyl
(--S-alkyl; also termed "alkylthio"), C.sub.5-C.sub.24 arylsulfanyl
(--S-aryl; also termed "arylthio"), C.sub.1-C.sub.20 alkyldithio
(--S--S-alkyl), C.sub.5-C.sub.24 aryldithio (--S--S-aryl),
carbamoyl (--(CO)--NH.sub.2); C.sub.2-C.sub.20 alkylcarbamoyl,
(--(CO)--NH-alkyl), C.sub.6-C.sub.20 arylcarbamoyl
(--(CO)--NH-aryl), silyl (--SiR.sub.3 wherein R is hydrogen or
hydrocarbyl), silyloxy (--O-silyl), phosphino (--PH.sub.2),
phosphonato (--P(O)(O.sup.-).sub.2), boryl (--BH.sub.2), borono
(--B(OH).sub.2), or boronato (--B(OR).sub.2 where R is alkyl or
other hydrocarbyl).
[0089] Q is typically selected from hydrocarbylene (e.g.,
C.sub.1-C.sub.20 alkylene, C.sub.2-C.sub.20 alkenylene,
C.sub.2-C.sub.20 alkynylene, C.sub.5-C.sub.24 arylene,
C.sub.6-C.sub.24 alkarylene, or C.sub.6-C.sub.24 aralkylene),
substituted hydrocarbylene (e.g., substituted C.sub.1-C.sub.20
alkylene, C.sub.2-C.sub.20 alkenylene, C.sub.2-C.sub.20 alkynylene,
C.sub.5-C.sub.24 arylene, C.sub.6-C.sub.24 alkarylene, or
C.sub.6-C.sub.24 aralkylene), heteroatom-containing hydrocarbylene
(e.g., C.sub.1-C.sub.20 heteroalkylene, C.sub.2-C.sub.20
heteroalkenylene, C.sub.2-C.sub.20 heteroalkynylene,
C.sub.5-C.sub.24 heteroarylene, heteroatom-containing
C.sub.6-C.sub.24 aralkylene, or heteroatom-containing
C.sub.6-C.sub.24 alkarylene), and substituted heteroatom-containing
hydrocarbylene (e.g., substituted C.sub.1-C.sub.20 heteroalkylene,
substituted C.sub.2-C.sub.20 heteroalkenylene, substituted
C.sub.2-C.sub.20 heteroalkynylene, substituted C.sub.5-C.sub.24
heteroarylene, substituted heteroatom-containing C.sub.6-C.sub.24
aralkylene, or substituted heteroatom-containing C.sub.6-C.sub.24
alkarylene), wherein, as noted elsewhere herein, two or more
substituents on adjacent atoms within Q may also be linked to form
an additional cyclic structure, which may be similarly substituted
to provide a fused polycyclic structure of two to about five cyclic
groups. Q is often, although again not necessarily, a two-atom
linkage or a three-atom linkage.
[0090] In a more preferred embodiment, Q is a two-atom linkage
having the structure --CR.sup.3R.sup.4--CR.sup.5R.sup.6-- or
--CR.dbd.CR.sup.5--, preferably
--R.sup.3R.sup.4--CR.sup.5R.sup.6--, wherein R.sup.3, R.sup.4,
R.sup.5, and R.sup.6 are independently selected from hydrogen,
hydrocarbyl, substituted hydrocarbyl, heteroatom-containing
hydrocarbyl, substituted heteroatom-containing hydrocarbyl, and
functional groups. Examples of functional groups here include
carboxyl, C.sub.1-C.sub.20 alkoxy, C.sub.5-C.sub.24 aryloxy,
C.sub.2-C.sub.20 alkoxycarbonyl, C.sub.5-C.sub.24 alkoxycarbonyl,
C.sub.2-C.sub.24 acyloxy, C.sub.1-C.sub.20 alkylthio,
C.sub.5-C.sub.24 arylthio, C.sub.1-C.sub.20 alkylsulfonyl, and
C.sub.1-C.sub.20 alkylsulfinyl, optionally substituted with one or
more moieties selected from C.sub.1-C.sub.12 alkyl,
C.sub.1-C.sub.12 alkoxy, C.sub.5-C.sub.14 aryl, hydroxyl,
sulfhydryl, formyl, and halide. R.sup.3, R.sup.4, R.sup.5, and
R.sup.6 are preferably independently selected from hydrogen,
C.sub.1-C.sub.12 alkyl, substituted C.sub.1-C.sub.12 alkyl,
C.sub.1-C.sub.12 heteroalkyl, substituted C.sub.1-C.sub.12
heteroalkyl, phenyl, and substituted phenyl. Alternatively, any two
of R.sup.3, R.sup.4, R.sup.5, and R.sup.6 may be linked together to
form a substituted or unsubstituted, saturated or unsaturated ring
structure, e.g., a C.sub.4-C.sub.12 alicyclic group or a C.sub.5 or
C.sub.6 aryl group, which may itself be substituted, e.g., with
linked or fused alicyclic or aromatic groups, or with other
substituents.
[0091] X.sup.1 and X.sup.2 are anionic ligands, and may be the same
or different, or are linked together to form a cyclic group,
typically although not necessarily a five- to eight-membered ring.
In preferred embodiments, X.sup.1 and X.sup.2 are each
independently hydrogen, halide, or one of the following groups:
C.sub.1-C.sub.20 alkyl, C.sub.5-C.sub.24 aryl, C.sub.1-C.sub.20
alkoxy, C.sub.5-C.sub.24 aryloxy, C.sub.2-C.sub.20 alkoxycarbonyl,
C.sub.6-C.sub.24 aryloxycarbonyl, C.sub.2-C.sub.24 acyl,
C.sub.2-C.sub.24 acyloxy, C.sub.1-C.sub.20 alkylsulfonato,
C.sub.5-C.sub.24 arylsulfonato, C.sub.1-C.sub.20 alkylsulfanyl,
C.sub.5-C.sub.24 arylsulfanyl, C.sub.1-C.sub.20 alkylsulfinyl,
C.sub.5-C.sub.24 arylsulfinyl, carboxyl, carboxylate, or triflate.
Optionally, X.sup.1 and X.sup.2 may be substituted with one or more
moieties, if the X.sup.1 and/or X.sup.2 substituent permits,
wherein the substituents are typically although not necessarily
selected from C.sub.1-C.sub.12 alkyl, C.sub.1-C.sub.12 alkoxy,
C.sub.5-C.sub.24 aryl, and halide, which may, in turn, with the
exception of halide, be further substituted with one or more groups
selected from halide, C.sub.1-C.sub.6 alkyl, C.sub.1-C.sub.6
alkoxy, and phenyl. In more preferred embodiments, X.sup.1 and
X.sup.2 are halide, benzoate, C.sub.2-C.sub.6 acyl, C.sub.2-C.sub.6
alkoxycarbonyl, C.sub.1-C.sub.6 alkyl, phenoxy, C.sub.1-C.sub.6
alkoxy, C.sub.1-C.sub.6 alkylsulfanyl, aryl, or C.sub.1-C.sub.6
alkylsulfonyl. In even more preferred embodiments, X.sup.1 and
X.sup.2 are each halide, CF.sub.3CO.sub.2, CH.sub.3CO.sub.2,
CFH.sub.2CO.sub.2, (CH.sub.3).sub.3CO,
(CF.sub.3).sub.2(CH.sub.3)CO, (CF.sub.3)(CH.sub.3).sub.2CO, PhO,
MeO, EtO, tosylate, mesylate, or trifluoromethanesulfonate. In the
most preferred embodiments, X.sup.1 and X.sup.2 are each
chloride.
[0092] L.sup.1 is a neutral electron donor ligand which is
coordinated to the metal center. L.sup.1 may be heterocyclic, in
which case it is generally selected from:
[0093] nitrogen-containing heterocycles such as pyridine,
bipyridine, pyridazine, pyrimidine, bipyridamine, pyrazine,
1,3,5-triazine, 1,2,4-triazine, 1,2,3-triazine, pyrrole,
2H-pyrrole, 3H-pyrrole, pyrazole, 2H-imidazole, 1,2,3-triazole,
1,2,4-triazole, indole, 3H-indole, 1H-isoindole,
cyclopenta(b)pyridine, indazole, quinoline, bisquinoline,
isoquinoline, bisisoquinoline, cinnoline, quinazoline,
naphthyridine, piperidine, piperazine, pyrrolidine, pyrazolidine,
quinuclidine, imidazolidine, picolylimine, purine, benzimidazole,
bisimidazole, phenazine, acridine, and carbazole;
[0094] oxygen-containing heterocycles such as 2H-pyran, 4H-pyran,
2-pyrone, 4-pyrone, 1,2-dioxin, 1,3-dioxin, oxepin, furan,
2H-1-benzopyran, coumarin, coumarone, chromene, chroman-4-one,
isochromen-1-one, isochromen-3-one, xanthene, tetrahydrofuran,
1,4-dioxan, and dibenzofuran; and
[0095] mixed heterocycles such as isoxazole, oxazole, thiazole,
isothiazole, 1,2,3-oxadiazole, 1,2,4-oxadiazole, 1,3,4-oxadiazole,
1,2,3,4-oxatriazole, 1,2,3,5-oxatriazole, 3H-1,2,3-dioxazole,
3H-1,2-oxathiole, 1,3-oxathiole, 4H-1,2-oxazine, 2H-1,3-oxazine,
1,4-oxazine, 1,2,5-oxathiazine, o-isooxazine, phenoxazine,
phenothiazine, pyrano[3,4-b]pyrrole, indoxazine, benzoxazole,
anthranil, and morpholine.
[0096] L.sup.1 may also be an amine, an imine, a phosphine, an
ether, or a thioether.
[0097] Preferably, L.sup.1 is selected from pyridines, amines,
phosphines, imines, ethers, thioethers, furans, and pyrans.
[0098] When .alpha. is a single bond, L.sup.2 is selected from
NR.sup.7R.sup.8, PR.sup.7R.sup.8, N.dbd.CR.sup.7R.sup.8, and
R.sup.7C.dbd.NR.sup.8, where R.sup.7 and R.sup.8 are independently
selected from substituted and/or heteroatom-containing
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, C.sub.5-C.sub.24 aryl, or R.sup.7 and R.sup.8 taken
together can form a cyclic group, e.g., piperidyl (including
substituted piperidyl). Any functional groups present on L.sup.1,
L.sup.2, R.sup.7, or R.sup.8 will generally be selected from the Fn
groups set forth above. Examples of preferred such catalysts are
those wherein L.sup.2 is NR.sup.7R.sup.8, having the structure of
formula (II) 5
[0099] wherein Q, R.sup.1, R.sup.2, R.sup.7, R.sup.8, X.sup.1,
X.sup.2, L.sup.1, Y, Z, .beta., and p are as defined above.
Preferred R.sup.7 and R.sup.8 substituents in this embodiment are
C.sub.1-C.sub.12 alkyl or C.sub.5-C.sub.12 aryl, e.g., methyl,
isopropyl, t-butyl, cyclohexyl, and phenyl, and preferred Y groups
are --CH.sub.2--, --CH.sub.2CH.sub.2-- and substituted analogs
thereof. Other preferred catalysts, wherein L.sup.2 is
PR.sup.7R.sup.8, have the structure of formula (III) 6
[0100] wherein Q, R.sup.1, R.sup.2, R.sup.7, R.sup.8, X.sup.1,
X.sup.2, Y, Z, L.sup.1, .beta., and p are as defined above,
preferred R.sup.7 and R.sup.8 substituents are C.sub.1-C.sub.12
alkyl or C.sub.5-C.sub.12 aryl, e.g., phenyl, and preferred Y
groups are as set forth for complexes of formula (II). Particularly
preferred catalytic complexes encompassed by formulae (II) and
(III) include, but are not limited to, the following: 7
[0101] L.sup.2 and Z can be linked through an unsaturated bond,
i.e., the dashed line indicating a bond at a may also represent a
double bond or a bond linking adjacent atoms in an aromatic ring.
When L.sup.2 and Z are linked through an unsaturated bond, L.sup.2
is selected from NR.sup.7 and PR.sup.7, and preferably is NR.sup.7
where R.sup.7 is as defined previously. It will be appreciated that
when .alpha. represents an unsaturated bond, the complex may be
contain an imine ligand (i.e., containing the moiety
--Z.dbd.NR.sup.7), or may contain a pyridine ring in which N and Z
are adjacent atoms in a pyridyl group. Examples of preferred such
catalysts in which the complex contains a pyridine ring or an imine
moiety are encompassed by structural formulae (IV) and (V),
respectively: 8
[0102] In formulae (IV) and (V), Q, R.sup.1, R.sup.2, R.sup.7,
R.sup.8, X.sup.1, X.sup.2, Y, Z, L.sup.1, .beta., and p are as
defined above, preferred R.sup.7 substituents are C.sub.1-C.sub.12
alkyl or C.sub.5-C.sub.12 aryl, e.g., methyl, isopropyl, t-butyl,
cyclohexyl, and phenyl, and preferred Y groups are substituted or
unsubstituted methylene or ethylene linkages.
[0103] Particularly preferred catalytic complexes encompassed by
formulae (IV) and (V) include, but are not limited to, the
following: 910
[0104] Y and Z are linkages independently selected from
hydrocarbylene (e.g., C.sub.1-C.sub.20 alkylene, C.sub.2-C.sub.20
alkenylene, C.sub.2-C.sub.20 alkynylene, C.sub.5-C.sub.24 arylene,
C.sub.6-C.sub.24 alkarylene, or C.sub.6-C.sub.24 aralkylene),
substituted hydrocarbylene (e.g., substituted C.sub.1-C.sub.20
alkylene, C.sub.2-C.sub.20 alkenylene, C.sub.2-C.sub.20 alkynylene,
C.sub.5-C.sub.24 arylene, C.sub.6-C.sub.24 alkarylene, or
C.sub.6-C.sub.24 aralkylene), heteroatom-containing hydrocarbylene
(e.g., C.sub.1-C.sub.20 heteroalkylene, C.sub.2-C.sub.20
heteroalkenylene, C.sub.2-C.sub.20 heteroalkynylene,
C.sub.5-C.sub.24 heteroarylene, heteroatom-containing
C.sub.6-C.sub.24 aralkylene, or heteroatom-containing
C.sub.6-C.sub.24 alkarylene), substituted heteroatom-containing
hydrocarbylene (e.g., substituted C.sub.1-C.sub.20 heteroalkylene,
substituted C.sub.2-C.sub.20 heteroalkenylene, substituted
C.sub.2-C.sub.20 heteroalkynylene, substituted C.sub.5-C.sub.24
heteroarylene, substituted heteroatom-containing C.sub.6-C.sub.24
aralkylene, or substituted heteroatom-containing C.sub.6-C.sub.24
alkarylene), --O--, --S--, --NR.sup.9--, and --PR.sup.9--, wherein
R.sup.3 is selected from hydrogen, hydrocarbyl (e.g.,
C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20
alkynyl, C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl,
C.sub.6-C.sub.24 aralkyl, etc.), substituted hydrocarbyl (e.g.,
substituted C.sub.1-C.sub.20 alkyl, C.sub.2-C.sub.20 alkenyl,
C.sub.2-C.sub.20 alkynyl, C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24
alkaryl, C.sub.6-C.sub.24 aralkyl, etc.), heteroatom-containing
hydrocarbyl (e.g., heteroatom-containing C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl,
C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl, C.sub.6-C.sub.24
aralkyl, etc.), and substituted heteroatom-containing hydrocarbyl
(e.g., substituted heteroatom-containing C.sub.1-C.sub.20 alkyl,
C.sub.2-C.sub.20 alkenyl, C.sub.2-C.sub.20 alkynyl,
C.sub.5-C.sub.24 aryl, C.sub.6-C.sub.24 alkaryl, C.sub.6-C.sub.24
aralkyl, etc.). Any functional groups present on Z, Y, and/or
R.sup.9 will generally be selected from the Fn moieties above.
[0105] Organic diradicals that can serve as Y and/or Z include, by
way of example, the following groups: methylene (VI), ethylene
(VII), vinylene (VIII), phenylene (IX), cyclohexylene (X), and
naphthylenes (XI) and (XII). 11
[0106] These organic diradicals may also serve as the linkage
Q.
[0107] In one particularly preferred embodiment of the invention, M
is ruthenium, Q is ethylene (II), X.sup.1 and X.sup.2 are chloride,
and p is zero. In a more preferred embodiment, R.sup.1 and R.sup.2
are mesityl (2,4,6-trimethylphenyl). In an even more preferred
embodiment of the invention, n is zero.
[0108] Exemplary catalysts of the invention are 2a and 2b, the
molecular structures of which are provided above and in FIG. 2,
wherein M is ruthenium, L.sup.2 is substituted or unsubstituted
pyridyl, R.sup.1 and R.sup.2 are mesityl (2,4,6-trimethylphenyl), Q
is ethylene (II), X.sup.1 and X.sup.2 are chloride, Y is ethylene
(II), m is 1, and n and p are zero. These new catalysts can be
prepared by reacting RuCl.sub.2(sIMes)(PCy.sub.3)(CHPh) (Catalyst
1) and 2-(3-butenyl)pyridine in dichloromethane at 40.degree. C.
(see Example 1). It has surprisingly found that depending on the
reaction time, catalyst 2a can be obtained either in pure form or
as a mixture of isomers 2a and 2b. This finding was quite
surprising, because the known ruthenium carbene olefin metathesis
catalysts typically have a configuration like that of 2a, namely a
C.sub.S symmetric square pyramidal geometry where the apical
position is occupied by the carbene ligand, and the equatorial
positions by two trans anionic ligands and two trans neutral
electron donating ligands. In the case of 2b, the complex is of
C.sub.1 symmetry and contains two equatorial cis anionic ligands
and two equatorial cis neutral electron donating ligands. X-ray
structures were obtained for 2a and 2b (see ORTEP diagrams in FIGS.
3 and 4). Catalyst 2a can also be prepared by reaction of
(sIMes)(py).sub.2(Cl).sub.2Ru.dbd.CHPh (complex 3) with 1.5
equivalent of 2-(3-butenyl)-pyridine in dichloromethane at room
temperature for 30 minutes (Example 2). In addition, this method is
amenable to the synthesis of complexes
(sIMes)(Cl).sub.2Ru(CH(CH.sub.2).s-
ub.2--C,N-2-(4-Me)-C.sub.5H.sub.3N) and
Ru(CH(CH.sub.2).sub.2--C,N-2-(6-Me- )-C.sub.5H.sub.3N), also shown
in FIG. 7.
[0109] The catalysts of the invention may be synthesized and used
in catalyzing olefin metathesis reactions using the procedures
described in the examples herein or variations thereof which will
be apparent to one of skill in the art.
[0110] Another embodiment of the present invention is a method for
the use of the present catalysts, including 2a and 2b, for the
metathesis of olefins. Surprisingly, both isomers exhibit large
differences in olefin metathesis activity (e.g., in RCM and ROMP).
These activity differences enable tuning of the catalyst by simple
isomerization of the complex in lieu of the strategies of the prior
art, such as utilization of additives or complicated and
time-consuming catalyst design involving ligand exchanges. The
catalysts may be attached to a solid support; as understood in the
field of catalysis, suitable solid supports may be of synthetic,
semi-synthetic, or naturally occurring materials, which may be
organic or inorganic, e.g., polymeric, ceramic, or metallic.
Attachment to the support will generally, although not necessarily,
be covalent, and the covalent linkage may be direct or indirect, if
indirect, typically between a functional group on a support surface
and a ligand or substituent on the catalytic complex. The reactions
are carried out under conditions normally used in olefin metathesis
reactions catalyzed by the Grubbs family of metathesis catalysts.
See, e.g., U.S. Pat. Nos. 5,312,940, 5,342,909, 5,831,108,
5,969,170, 6,111,121, and 6,211,391 to Grubbs et al.
[0111] As indicated by the results in the examples, various
modifications to the basic catalyst structures herein can increase
or decrease latency period as desired.
[0112] It is to be understood that while the invention has been
described in conjunction with the preferred specific embodiments
thereof, that the foregoing description as well as the examples
that follow are intended to illustrate and not limit the scope of
the invention. Other aspects, advantages and modifications within
the scope of the invention will be apparent to those skilled in the
art to which the invention pertains.
[0113] All patents, patent applications, and publications mentioned
herein are hereby incorporated by reference in their
entireties.
EXAMPLE 1
Synthesis of Catalyst 2a: Method A
[0114] A 250 mL round bottom Schlenk flask equipped with a stir bar
was charged with complex 1,
(sIMes)(PCy.sub.3)(Cl).sub.2Ru.dbd.CHPh, (10.0 g; 11.8 mmol). The
flask was capped, sparged with argon for 15 minutes, and charged
with anhydrous CH.sub.2Cl.sub.2 (118 mL) via cannula.
2-(3-butenyl)pyridine (2.4 g, 17.7 mmol) was then added via syringe
and the reaction mixture was heated to 40.degree. C. for 5-6 hours.
The reaction mixture was concentrated to dryness and the residue
triturated with degassed, chilled methanol. The solid was collected
on a frit and washed with chilled methanol (2.times.25 mL) to give
catalyst 2a,
(sIMes)(Cl).sub.2Ru(CH(CH.sub.2).sub.2--C,N-2-C.sub.5H.sub.4N)--C.sub.s,
(5.6 g; 9.4 mmol) as a pale green solid upon drying. Yield:
80%.
EXAMPLE 2
Synthesis of Catalyst 2a: Method B
[0115] In the glove box a vial was charged with
2-(3-butenyl)pyridine (24 mg, 0.18 mmol) and CH.sub.2Cl.sub.2 (2
mL). Complex 3, (sIMes)(py).sub.2(Cl).sub.2Ru.dbd.CHPh, (86 mg;
0.12 mmol) was then added as a solid and the reaction allowed to
stir at room temperature for 30 minutes. The volatiles were removed
under vacuum and the residue triturated with hexanes. The solid was
collected, washed with hexanes (2.times.1 mL) and dried under
vacuum to give catalyst 2a,
(sIMes)(Cl).sub.2Ru(CH(CH.sub.2).sub.2--C,N-2-C.sub.5H.sub.4N)--C,
(60 mg; 0.10 mmol) as a pale green solid upon drying. Yield: 85%.
.sup.1H NMR (CD.sub.2Cl.sub.2): .delta. 18.46 (t,
.sup.3J.sub.HH=2.7 Hz, 1 H, Ru.dbd.CH), 7.64 (d, .sup.3J.sub.HH=4.8
Hz, 1 H, Py), 7.52 (t, .sup.3J.sub.HH=7.2 Hz, 1 H, Py), 7.14
(d,.sup.3J.sub.HH=7.8 Hz, 1H, Py), 7.07 (s, 4 Mes), 6.99 (t,
.sup.3J.sub.HH=6.9 Hz, 1 H, Py), 4.09 (s, 4 H, sIMes), 3.55 (t,
.sup.3J.sub.HH=5.7 Hz, 2H, CH.sub.2-Py), 2.50 (s, 12 H,
Mes-CH.sub.3), 2.41 (s, 6 H, Mes-CH.sub.3), 1.70 (m, 2 H,
Ru.dbd.CH--CH.sub.2). .sup.13C{.sup.1H} NMR (CD.sub.2Cl.sub.2):
.delta. 339.18 (Ru.dbd.CHCH2), 216.52 (Ru--C(N).sub.2), 162.64,
158.34, 149.54, 138.96, 138.83, 136.96, 129.60, 124.51, 121.82,
54.45, 51.92, 34.30, 21.32, 19.58.
EXAMPLE 3
Conversion of Catalyst 2a to Catalyst 2b
[0116] In the glove box, a 0.1 M solution of catalyst 2a in
CD.sub.2Cl.sub.2 was prepared and transferred to an NMR tube, which
was capped and taken out of the glove box. The NMR tube was left in
an oil bath at 40.degree. C. and the reaction was monitored by
.sup.1H NMR spectroscopy. The ratio of 2b to 2a in the mixture was
30/70 after 24 hours; 60/40 after 48 hours; 70/30 after 72 hours;
and 78/22 after 96 hours.
EXAMPLE 4
Conversion of Catalyst 2b to 2a
[0117] In the glove box, a 0.1 M solution of catalyst 2b in
CD.sub.2Cl.sub.2 was prepared and transferred to an NMR tube, which
was capped and taken out of the glove box. The NMR tube was left in
an oil bath at 40.degree. C. and the reaction was monitored by
.sup.1H NMR spectroscopy. The ratio of 2b to 2a in the mixture was
83/17 after 24 hours. .sup.1H NMR spectroscopy also showed that the
isomerization of 2b was accompanied with some catalyst
decomposition, making it complicated to analyze the reaction
mixture beyond 24 hours.
EXAMPLE 5
Synthesis of Catalyst 4
[0118] In the glove box, a flask was charged with
2-(3-butenyl)-4-methylpy- ridine (40 mg, 0.27 mmol) and
CH.sub.2Cl.sub.2 (5 mL). Complex 3,
(sIMes)(py).sub.2(Cl).sub.2Ru.dbd.CHPh, (114 mg; 0.16 mmol) was
then added as a solid and the reaction allowed to stir at room
temperature for 30 minutes. The volatiles were removed under vacuum
and the residue was redissolved in C.sub.6H.sub.6 (1 mL) and
precipitated with pentane (10 mL). The solid was collected, washed
with pentane (3.times.5 mL) and dried under vacuum to give catalyst
4, (sIMes)(Cl).sub.2Ru(CH(CH.sub.2).s-
ub.2--C,N-2-(4-Me)-C.sub.5H.sub.3N)--C.sub.s, (80 mg; 0.13 mmol) as
a light brown solid upon drying. Yield: 84%. .sup.1H NMR
(CD.sub.2Cl.sub.2): .delta. 18.44 (t, .sup.3J.sub.HH=3.3 Hz, 1 H,
Ru.dbd.CH), 7.42 (d, .sup.3J.sub.HH=5.7 Hz, 1 H, Py), 7.02 (s, 4 H,
Mes), 6.95 (s, 1 H, Py), 6.80 (d, .sup.3J.sub.HH=4.2 Hz, 1 H, Py),
4.06 (s, 4 H, sIMes), 3.46 (t, .sup.3J.sub.HH=6.0 Hz, 2 H,
CH.sub.2-Py), 2.45 (s, 12 H, Mes-CH.sub.3), 2.37 (s, 6 H,
Mes-CH.sub.3), 2.27 (s, 3 H, Py-CH.sub.3), 1.66 (m, 2 H,
Ru.dbd.CH--CH.sub.2). .sup.13C{.sup.1H} NMR (CD.sub.2Cl.sub.2):
.delta. 339.16 (Ru.dbd.CHCH2), 216.91 (Ru--C(N).sub.2), 161.97,
148.96, 148.87, 138.99, 138.83, 129.63, 125.43, 122.98, 54.62,
51.95, 34.13, 21.35, 21.01, 19.64.
EXAMPLE 6
Synthesis of Catalyst 5
[0119] In the glove box, a flask was charged with
2-(3-butenyl)-6-methylpy- ridine (50 mg, 0.34 mmol) and
CH.sub.2Cl.sub.2 (5 mL). Complex 3,
(sIMes)(Py).sub.2(Cl).sub.2Ru.dbd.CHPh, (98 mg; 0.14 mmol) was then
added as a solid and the reaction allowed to stir at room
temperature for 30 minutes. The volatiles were removed under vacuum
and the residue was redissolved in C.sub.6H.sub.6 (1 mL) and
precipitated with pentane (10 mL). The solid was collected, washed
with pentane (3.times.5 mL) and dried under vacuum to give catalyst
5, (sIMes)(Cl).sub.2Ru(CH(CH.sub.2).s-
ub.2--C,N-2-(6-Me)-C.sub.5H.sub.3N)--C.sub.s, (57 mg; 0.094 mmol)
as a light brown solid upon drying. Yield: 69%. .sup.1H NMR
(CD.sub.2Cl.sub.2): .delta. 18.33 (t, .sup.3J.sub.HH=3.6 Hz, 1 H,
Ru.dbd.CH), 7.34 (t, .sup.3J.sub.HH=7.5 Hz, 1 H, Py), 7.03 (s, 4H,
Mes), 6.97 (d, .sup.3J.sub.HH=7.8 Hz, 1 H, Py), 6.75 (d,
.sup.3J.sub.HH=7.8 Hz, 1 H, Py), 4.05 (m, 4 H, SIMes), 2.91 (m, 4
H, Ru.dbd.CH--CH.sub.2--CH.sub- .2-Py), 2.61 (br s, 6 H,
Mes-CH.sub.3), 2.37 (s, 6 H, Mes-CH.sub.3), 2.31 (br s, 6 H,
Mes-CH.sub.3), 2.01 (s, 3 H, Py-CH.sub.3). .sup.13C{.sup.1H} NMR
(CD.sub.2Cl.sub.2): .delta. 343.54 (Ru.dbd.CHCH2), 218.21
(Ru--C(N).sub.2), 160.62, 160.55, 140.45, 139.29, 138.73, 137.88,
136.65, 129.79, 128.82, 123.03, 122.13, 52.04, 51.24, 34.66, 32.20,
22.86, 21.76, 21.34, 20.37, 18.51.
[0120] It should be noted that the .sup.1H NMR spectra for
catalysts 2a, 4 and 5 are consistent with complexes of C.sub.s
symmetry, where the resonances for each of the para methyl groups
of the mesityl rings, the ortho methyl groups of the same rings and
the ethylene bridge of the sIMes ligand appear as singlets [the
.sup.1H NMR singlets described are consistent with a C.sub.s
symmetry and free rotation of the sIMes ligand around the Ru--C
bond (on the NMR time-scale)]. The alkylidene proton resonances
near 18 ppm appear as triplets due to coupling to the methylene
protons (.sup.3J.sub.HH=2.7-3.6 Hz).
EXAMPLE 7
Synthesis of Catalyst 2b
[0121] A 220 mL round bottom Schlenk flask equipped with a stir bar
was charged with complex 1,
(sIMes)(PCy.sub.3)(Cl).sub.2Ru.dbd.CHPh, (5.0 g; 5.9 mmol). The
flask was capped, sparged with argon for 15 minutes, and charged
with anhydrous CH.sub.2Cl.sub.2 (60 mL) via cannula.
2-(3-butenyl)pyridine (1.2 g, 8.9 mmol) was then added via syringe
and the reaction mixture was heated to 40.degree. C. for 3-4 days.
The reaction mixture was concentrated to dryness and the residue
triturated with degassed, chilled methanol (15 mL). The solid was
collected on a frit and washed with methanol (2.times.10 mL) to
give catalyst 2b,
(sIMes)(Cl).sub.2Ru(CH(CH.sub.2).sub.2--C,N-2-C.sub.5H4N)--C.sub.1,
(1.3 g; 2.2 mmol) as an orange-brown solid upon drying. Yield: 37%.
.sup.1H NMR (CD.sub.2Cl.sub.2): .delta. 19.14 (t,
.sup.3J.sub.HH=3.3 Hz, 1 H, Ru.dbd.CH), 7.54 (d, .sup.3J.sub.HH=7.8
Hz, 1 H, Py), 7.49 (t, .sup.3J.sub.HH=5.1 Hz, 1 H, Py), 7.25 (s, 1
H, Mes), 7.06 (s, 1 H, Mes), 7.03 (d, .sup.3J.sub.HH=7.8 Hz, 1 H,
Py), 6.90 (s, 1 H, Mes), 6.88 (s, 1 H, Mes), 6.81 (t,
.sup.3J.sub.HH=6.6 Hz, 1 H, Py), 4.15 (m, (m, 2 H, SIMes), 3.90 (m,
2 H, sIMes), 3.00 (m, 2 H, CH.sub.2-Py), 2.88 (s, 3 H,
Mes-CH.sub.3), 2.69 (s, 3 H, Mes-CH.sub.3), 2.40 (s, 3 H,
Mes-CH.sub.3), 2.34 (s, 3 H, Mes-CH.sub.3), 1.96 (s, 3 H,
Mes-CH.sub.3), 1.78 (m, 1 H, Ru.dbd.CH--CH.sub.2), 1.45 (s, 3 H,
Mes-CH.sub.3), 1.21 (m, 1 H, Ru.dbd.CH--CH.sub.2).
.sup.13C{.sup.1H} NMR (CD.sub.2Cl.sub.2): .delta. 319.04
(Ru.dbd.CHCH2), 218.94 (Ru--C(N).sub.2), 161.71, 154.02, 139.51,
138.94, 138.32, 137.90, 135.57, 134.97, 132.96, 130.26, 129.53,
129.34, 129.16, 128.65, 122.94, 120.00, 50.54, 49.23, 34.87, 20.52,
20.27, 19.25, 18.92, 18.39, 17.56.
[0122] Catalyst 2b appears as a ruthenium carbene of C.sub.1
symmetry, displaying six nonequivalent methyl groups on the mesityl
rings, four nonequivalent protons on the ethylene bridge of the
sIMes ligand and 4 nonequivalent protons on the ethylene bridge of
the pyridyl ligand in the .sup.1H NMR spectrum. The carbene
resonance of 2b also appears as a triplet (.delta.19.14 ppm;
.sup.3J.sub.HH=3.3 Hz). Pure isolated 2a, dissolved in
CD.sub.2Cl.sub.2 (0.1 M), is slowly converted to a 22:78 mixture of
2a:2b at 40.degree. C. over the course of 96 hours and pure
isolated 2b forms a similar mixture under the same conditions. It
may therefore be concluded that 2a and 2b are isomers in
equilibrium where 2b is the thermodynamically favored species and
K.sub.eq=0.28. Attempts to measure the kinetics of the approach to
equilibrium were hampered by a decomposition process concurrent
with the 2a2b isomerization process.
[0123] Crystals suitable for X-ray analysis were obtained for
catalysts 2a and 2b (ORTEP views of 2a and 2b are shown in FIGS. 9
and 10, respectively). Both complexes display square pyramidal
geometries, where the chloride, pyridine and NHC ligands occupy the
equatorial positions and the alkylidene occupies the axial
position. In 2a, the chloride ligands are trans one to another
[Cl(1)-Ru(1)-Cl(2)=164.41(1)] as are the neutral ligands
[C(1)-Ru(1)-N(3)=170.21(4)]. This geometry is typical for ruthenium
olefin metathesis catalysts and is consistent with the .sup.1H NMR
spectrum of 2a. On the other hand, 2b possesses cis chloride
ligands (Cl(1)-Ru(1)-Cl(2)=85.93(2)) and cis neutral ligands
(C(1)-Ru(1)-N(3)=98.04(8)), which explain the C.sub.1 symmetry
deduced from the spectroscopic data. This type of ligand
arrangement is relatively rare for ruthenium carbene complexes,
although it has been observed in a few cases [ruthenium complexes
containing chelating bisphosphine ligands and cis chlorides have
been described: see, e.g., Hansen et al. (1999) Angew. Chem., Int.
Ed. 38, 1273-1276; Hansen et al. (1999) Chem. Eur. J. 5, 557-566;
Volland et al. (2001) Organomet. Chem. 617, 288-291; Nieczypor et
al. (2001). J. Organomet. Chem. 625, 58-66; Pruhs et al. (2004)
Organometallics 23, 280-287; Slugovc et al. (2004) Organometallics,
23, 3622-3626. A related complex with cis neutral ligands and cis
anionic pentafluorophenoxide ligands has been reported: see Conrad
et al. (2003) Organometallics 22, 3634-3636; a related vinylcarbene
ruthenium complex containing cis chlorides has also been reported:
see Trnka et al. (2001) Organometallics 20, 3845-3847]. The
Ru(1)-N(3) distance of 2.1355(9) .ANG. in 2a is significantly
longer than that of 2.098(2) .ANG. in 2b, due to the trans
influence of the NHC ligand. Similarly, the Ru(1)-Cl(2) distance in
2b (2.3883(6) .ANG.) is longer than that in 2a (2.3662(3)
.ANG.).
EXAMPLE 8
Synthesis of Catalyst Ru(C4-PPh.sub.2) (6)
[0124] In the glove box, a flask was charged with
(4-pentenyl)diphenyl phosphine (49 mg, 0.19 mmol) and
CH.sub.2Cl.sub.2 (5 mL). Catalyst 3,
RuCl.sub.2(sIMes)(py).sub.2(CHPh), (127 mg; 0.17 mmol) was then
added as a solid and the reaction allowed to stir at room
temperature for 30 minutes. The volatiles were removed under vacuum
and the residue was washed with pentane (2.times.2 mL). The solid
was redissolved in CH.sub.2Cl.sub.2 (5 mL) and heated to 40.degree.
C. for 12 h, after which volatiles were removed under vacuum. The
solid was purified by column chromatography (5% Et.sub.2O/pentane,
then 25% Et.sub.2O/pentane) and dried under vacuum to give catalyst
6. (59 mg; 0.082 mmol) as a light brown solid upon drying. Yield:
47%. .sup.1H NMR (CD.sub.2Cl.sub.2): .delta. 18.60 (td,
.sup.3J.sub.HH=6.3 Hz, .sup.3J.sub.PH=1.8 Hz, 1 H, Ru.dbd.CH), 7.30
(m, 2 H, PPh.sub.2), 7.18 (m, 4 H, PPh.sub.2), 6.97 (s, 4 H, Mes),
6.89 (m, 4 H, PPh.sub.2), 4.07 (m, 4 H, sIMes), 2.79 (q,
.sup.3J.sub.HH=6.3 Hz, 2 H, Ru.dbd.CH--CH.sub.2--CH.sub.2), 2.53
(s, 6 H, Mes-CH.sub.3), 2.39 (s, 6 H, Mes-CH.sub.3), 2.35 (s, 6 H,
Mes-CH.sub.3), 2.30 (m, 2 H, CH.sub.2--CH.sub.2--PPh.sub.2), 1.53
(m, 2 H, CH.sub.2--CH.sub.2--CH.sub.2--PPh.sub.2).
.sup.31P{.sup.1H} NMR (CD.sub.2Cl.sub.2): .delta. 45.49.
EXAMPLE 9
Synthesis of Catalyst Ru(Ph-Im) (7)
[0125] In the glove box, a flask was charged with catalyst 3,
RuCl.sub.2(sIMes)(py).sub.2(CHPh), (154.7 mg; 0.21 mmol) and
CH.sub.2Cl.sub.2 (5 mL).
(2,2-dimethyl-pent-4-enylidene)-phenyl-amine (60 mg, 0.32 mmol) was
then added via syringe and the reaction allowed to stir at room
temperature for 15 minutes. The volatiles were removed under vacuum
and the residue was washed with pentane (2.times.2 mL). The solid
was redissolved in C.sub.6H.sub.6 (2 mL) and precipitated with
pentane (20 mL). The solid was collected, washed with pentane
(3.times.5 mL) and dried under vacuum to give catalyst 7 (115.6 mg;
0.18 mmol) as an olive green solid upon drying. Yield: 83%. .sup.1H
NMR (CD.sub.2Cl.sub.2): .delta. 18.80 (t, .sup.3J.sub.HH=5.4 Hz, 1
H, Ru.dbd.CH), 7.64 (s, 1 H, C(.dbd.N)H), 7.2-6.9 (m, 9 H, Ar--H),
4.01 (s, 4 H, sIMes), 3.02 (d,.sup.3J.sub.HH=5.4 Hz, 2 H,
RU.dbd.CH--CH.sub.2--CMe.sub.2), 2.5-2.3 (m, 18 H, Mes-CH.sub.3),
1.07 (s, 6 H, CMe.sub.2). .sup.13C{.sup.1H} NMR (CD.sub.2Cl.sub.2):
.delta. 345.10 (Ru.dbd.CHCH2), 218.03 (Ru--C(N).sub.2), 176.96
(Ru--N.dbd.C), 149.63, 138.81, 129.82, 129.40, 127.12, 122.48,
64.30, 51.82, 42.69, 26.89, 21.46, 19.28.
EXAMPLE 10
Synthesis of Catalyst Ru(Cy-Im) (8)
[0126] In the glove box, a flask was charged with catalyst 3,
RuCl.sub.2(sIMes)(py).sub.2(CHPh), (191.5 mg; 0.26 mmol) and
CH.sub.2Cl.sub.2 (5 mL).
(2,2-dimethyl-pent-4-enylidene)-cyclohexylamine (74 mg, 0.38 mmol)
was then added via syringe and the reaction allowed to stir at room
temperature for 15 minutes. The volatiles were removed under vacuum
and the residue was washed with pentane (2.times.2 mL). The solid
was redissolved in C.sub.6H.sub.6 (2 mL) and precipitated with
pentane (20 mL). The solid was collected, washed with pentane
(3.times.5 mL) and dried under vacuum to give catalyst 8 (146.1 mg;
0.22 mmol) as an olive green solid upon drying. Yield: 84%. .sup.1H
NMR (CD.sub.2Cl.sub.2): .delta. 18.56 (t, .sup.3J.sub.HH=5.4 Hz, 1
H, Ru.dbd.CH), 7.41 (s, .sup.3J.sub.HH=5.4 Hz, 1 H, C(.dbd.N)H),
7.00 (br s, 4 H, Mes), 4.00 (br s, 4 H, sIMes), 2.96 (d,
.sup.3J.sub.HH=5.7 Hz, 2 H, Ru.dbd.CH--CH.sub.2--CMe.sub.2),
2.7-2.2 (br m, 12 H, Mes-CH.sub.3), 2.34 (s, 6 H, Mes-CH.sub.3),
1.7-0.8 (m, 11 H, Cy), 0.91 (s, 6 H, CMe.sub.2).
EXAMPLE 11
Synthesis of Catalyst Ru(iPr-Im) (9)
[0127] In the glove box, a flask was charged with Catalyst 3,
RuCl.sub.2(sIMes)(py).sub.2(CHPh) (239 mg; 0.33 mmol) and
CH.sub.2Cl.sub.2 (5 mL).
(2,2-dimethyl-pent-4-enylidene)-isopropyl-amine (76 mg, 0.38 mmol)
was then added via syringe and the reaction allowed to stir at room
temperature for 15 minutes. The volatiles were removed under
vacuum, the residue was redissolved in C.sub.6H.sub.6 (2 mL) and
precipitated with pentane (20 mL). The solid was collected, washed
with pentane (3.times.5 mL) and dried under vacuum to give catalyst
3 (162 mg; 0.26 mmol) as a pale green solid upon drying. Yield:
80%. .sup.1H NMR (CD.sub.2Cl.sub.2): .delta. 18.58 (t,
.sup.3J.sub.HH=5.4 Hz, 1 H, Ru.dbd.CH), 7.41 (d, .sup.3J.sub.HH=1.5
Hz, 1H, C(.dbd.N)H), 6.99 (s, 4 H, Mes), 4.02 (br s, 4 H, sIMes),
3.32 (sept. d, J.sub.HH=6.6, 1.5 Hz, 1H, NCH(CH.sub.3).sub.2), 2.96
(d, .sup.3J.sub.HH=5.4 Hz, 2 H, Ru.dbd.CH--CH.sub.2--CMe.sub.2),
2.42 (br s, 12 H, Mes-CH.sub.3), 2.34 (s, 6 H, Mes-CH.sub.3), 0.92
(s, 6 H, CMe.sub.2). 0.90 (d, .sup.3J.sub.HH=6.9 Hz, 6 H,
NCH(CH.sub.3).sub.2). .sup.13C{.sup.1H} NMR (CD.sub.2Cl.sub.2):
.delta. 345.17 (Ru.dbd.CHCH2), 219.54 (Ru--C(N).sub.2) 173.68,
138.91, 129.74, 64.21, 60.78, 51.60, 42.51, 26.96, 22.47, 21.36,
19.36 (br).
EXAMPLE 12
Synthesis of Catalyst Ru(tBu-Im) (10)
[0128] In the glove box, a flask was charged with Catalyst 3,
RuCl.sub.2(sIMes)(py).sub.2(CHPh) (188 mg; 0.26 mmol) and
CH.sub.2Cl.sub.2 (5 mL).
(2,2-dimethyl-pent-4-enylidene)-tert-butyl-amine (56 mg, 0.34 mmol)
was then added via syringe and the reaction allowed to stir at room
temperature for 15 minutes. The volatiles were removed under
vacuum, the residue was redissolved in C.sub.6H.sub.6 (2 mL) and
precipitated with pentane (20 mL). The solid was collected, washed
with pentane (3.times.5 mL) and dried under vacuum to give catalyst
10 (91 mg; 0.14 mmol) as pale green solid upon drying. Yield: 56%.
.sup.1H NMR (CD.sub.2Cl.sub.2): .delta. 18.37 (t,
.sup.3J.sub.HH=5.7 Hz, 1 H, Ru.dbd.CH), 7.43 (s, 1 H, C(.dbd.N)H),
7.04-6.94 (m, 4 H, Mes), 4.10-3.86 (m, 4 H, sIMes), 3.08 (d,
.sup.3J.sub.HH=5.4 Hz, 2 H, Ru.dbd.CH--CH.sub.2--CMe.sub.2), 2.59
(br s, 6 H, Mes-CH.sub.3), 2.34 (s, 6 H, Mes-CH.sub.3), 2.26 (br s,
6 H, Mes-CH.sub.3), 1.0 (s, 9 H, NCMe.sub.3), 0.91 (s, 6 H,
CMe.sub.2). .sup.13C{.sup.1H} NMR (CD.sub.2Cl.sub.2): .delta.
345.22 (Ru.dbd.CHCH2), 219.82 (Ru--C(N).sub.2), 172.97, 139.83,
139.13, 138.55, 137.92, 136.09, 129.83, 129.74, 64.05, 63.66,
51.75, 51.27, 43.02, 25.89, 26.77, 21.37, 20.21, 18.58.
EXAMPLE 13
Synthesis of Catalyst Ru(Me-Im) (11)
[0129] In the glove box, a flask was charged with Catalyst 3,
RuCl.sub.2(sIMes)(py).sub.2(CHPh) (143 mg; 0.20 mmol) and
CH.sub.2Cl.sub.2 (5 mL).
(2,2-dimethyl-pent-4-enylidene)-methyl-amine (30 mg, 0.24 mmol) was
then added via syringe and the reaction allowed to stir at room
temperature for 30 minutes. The volatiles were removed under
vacuum, the residue was redissolved in C.sub.6H.sub.6 (2 mL) and
precipitated with pentane (20 mL). The solid was collected, washed
with pentane (3.times.5 mL) and dried under vacuum to give catalyst
11 (93 mg; 0.16 mmol) as a green-brown solid upon drying. Yield:
84%. .sup.1H NMR (CD.sub.2Cl.sub.2): .delta. 18.80 (t,
.sup.3J.sub.HH=5.1 Hz, 1 H, Ru.dbd.CH), 7.42 (m, 1 H, C(.dbd.N)H),
7.00 (br s, 4 H, Mes), 4.05 (s, 4 H, sIMes), 2.73 (d,
.sup.4J.sub.HH=1.2 Hz, 3 H, C.dbd.NMe), 2.69 (d, .sup.3J.sub.HH=5.1
Hz, 2 H, Ru.dbd.CH--CH.sub.2--CMe.sub.2), 2.41 (s, 12 H,
Mes-CH.sub.3), 2.34 (s, 6 H, Mes-CH.sub.3), 0.93 (s, 6 H,
CMe.sub.2). .sup.13C{.sup.1H} NMR (CD.sub.2Cl.sub.2): .delta.
342.54 (Ru.dbd.CHCH2), 218.93 (Ru--C(N).sub.2), 175.29, 139.04,
138.87, 136.52, 129.61, 64.46, 51.85, 46.76, 41.83, 26.88, 21.37,
19.56.
EXAMPLE 14
Synthesis of Catalyst 12
[0130] In the glove box, a flask was charged with Catalyst 3,
RuCl.sub.2(SIMes)(PCy.sub.3)(CHPh) (5.0 g; 5.9 mmol) and
CH.sub.2Cl.sub.2 (60 mL). Ortho-(N,N)-dimethylaminostyrene (1.7 g;
11.8 mmol; 2 equiv), prepared according to a literature procedure
(see J. Chem. Soc. 1958, 2302), was added and the reaction mixture
was stirred at 40.degree. C. for 24 hours under inert atmosphere.
The volatiles were removed under vacuum, the residue was triturated
with methanol (10 mL) and the solid collected on a fritted glass
filtration funnel. The solid was then washed with additional
methanol (2.times.10 mL) and hexanes (2.times.10 mL) before it was
dried under vacuum to give catalyst 12 (2.8 g; 4.6 mmol) as a green
solid. Yield: 78%. .sup.1H NMR (CD.sub.2Cl.sub.2): .delta. 16.85
(s, 1 H, Ru.dbd.CH), 7.58 (t, 1 H, Ar), 7.22 (d, 1 H, Ar), 7.10 (t,
1 H, Ar), 7.08 (s, 4 H, Mes), 6.82 (d, 1 H, Ar), 4.10 (br s, 4 H,
CH.sub.2CH.sub.2), 2.50 (s, 6 H, Mes-CH.sub.3), 2.48 (s, 12 H,
Mes-CH.sub.3), 2.40 (s, 6 H, NMe.sub.2).
EXAMPLE 15
Activity of Catalysts 1, 2a, 2b and 12: RCM of Diethylallyl
Malonate
[0131] The ring-closing metathesis of diethyldiallyl malonate was
used as a test reaction to compare the activity of the different
catalysts. For the comparison of catalysts 1, 2a, 2b and 12: 1 mol
% of catalyst was added to a 0.1 M solution of diethyldiallyl
malonate in dichloromethane and the reaction was allowed to proceed
at 25.degree. C. and was monitored by gas-chromatography (FIG. 10).
As shown in FIG. 10, 2a is much slower than 1 (<20% conversion
after 100 min versus.about.100% conversion, respectively, under the
conditions used), 2b is much slower than 2a (<2% conversion
after 100 min under the conditions used), and 12 is much slower
than 2b.
EXAMPLE 16
Activity of Catalysts 2a, 4 and 5: RCM of Diethylallyl Malonate
[0132] The ring-closing metathesis of diethyldiallyl malonate was
used as a test reaction to compare the activity of catalysts 2a, 4
and 5. In the dry box, 2.5 mol % of catalyst (0.0052 mmol) was
dissolved in C.sub.6D.sub.6 (0.65 mL) in an NMR tube fitted with a
teflon septum screw-cap. The resulting solution was allowed to
equilibrate in the NMR probe at 40.degree. C. Diethyldiallyl
malonate (50 .mu.L, 0.207 mmol, 0.30 M) was injected into the NMR
tube neat and the reaction was monitored by .sup.1H NMR
spectroscopy (FIG. 11). The olefinic resonances integrals of the
product relative to that of the starting material were measured
with the residual protio solvent peak used as an internal standard.
As shown in FIG. 11, 2a and 4 show similar reactivity in RCM, but 5
proved to initiate faster than 2a and 4, presumably due to steric
crowding of the ortho methyl group on the pyridine ligand.
EXAMPLE 17
Activity of Catalysts 2a, 7 and 8: RCM of Diethylallyl Malonate
[0133] As in Example 16, the ring-closing metathesis of
diethyldiallyl malonate was used as a test reaction to compare the
activity of catalysts 2a, 7 and 8. In the dry box, 2.5 mol % of
catalyst (0.0052 mmol) was dissolved in C.sub.6D.sub.6 (0.65 mL) in
an NMR tube fitted with a teflon septum screw-cap. The resulting
solution was allowed to equilibrate in the NMR probe at 40.degree.
C. Diethyldiallyl malonate (50 .mu.L, 0.207 mmol, 0.30 M) was
injected into the NMR tube neat and the reaction was monitored by
.sup.1H NMR spectroscopy (FIG. 12). The olefinic resonances
integrals of the product relative to that of the starting material
were measured with the residual protio solvent peak used as an
internal standard. As shown in FIG. 12, catalyst 7 is faster than
2a in RCM, while 8 is slower than 2a.
[0134] The foregoing test reaction was then re-run to compare
catalysts 7, 8, 9, 10, and 11, with the results given in FIG.
13.
EXAMPLE 18
Activity of Catalysts 6 and 8: RCM of Diethylallyl Malonate
[0135] As in Example 16, the ring-closing metathesis of
diethyldiallyl malonate was used as a test reaction to compare the
activity of catalysts 6 and 8. In the dry box, 2.5 mol % of
catalyst (0.0052 mmol) was dissolved in C.sub.6D.sub.6 (0.65 mL) in
an NMR tube fitted with a teflon septum screw-cap. The resulting
solution was allowed to equilibrate in the NMR probe at 60.degree.
C. Diethyldiallyl malonate (50 .mu.L, 0.207 mmol, 0.30 M) was
injected into the NMR tube neat and the reaction was monitored by
.sup.1H NMR spectroscopy (FIG. 14). The olefinic resonances
integrals of the product relative to that of the starting material
were measured with the residual protio solvent peak used as an
internal standard.
EXAMPLE 19
ROMP of Dicyclopentadiene (DCPD) using Catalysts 2a and 2b
[0136] Dicyclopentadiene containing 3.5% of tricyclopentadiene (100
g) was polymerized by addition of catalyst
(monomer/catalyst=30,000:1 mole:mole) at 30.degree. C. The
polymerization exotherms for the polymerization catalyzed by
catalysts 2a and 2b were measured and are shown in FIG. 15. In the
same way that catalyst 2b is much slower that 2a in RCM, 2b also
initiates the ROMP of DCPD more slowly than 2a. A ROMP of DCPD
using 2a reaches its exotherm within 3 minutes, while the same
polymerization catalyzed by 2b requires more than 25 minutes.
[0137] While not intending to be bound by theoretical
considerations, the difference in reactivity between 2a and 2b may
be due to the fact that the pyridine ligand in 2a is trans to the
strongly .sigma.-donating NHC ligand and therefore dissociates to
give the active 14-electron species much faster than in 2b. The
difference in activity between 2a and 2b may be purely due to a
disparity in initiation rates and does not give any clues regarding
the conformation of the metallocyclobutane metathesis
intermediates. In other words, the fact that 2a is a faster
catalyst than 2b does not imply that the olefin approaching the
14-electron species must necessarily bind trans to the NHC ligand
[see, e.g., Trnka, T. M.; Day, M. W.; Grubbs, R. H. Organometallics
2001, 20, 3845-3847 for a discussion on the conformation of olefin
metathesis intermediates]. Substitution on the pyridine ring has a
much less dramatic effect on catalytic activity.
[0138] In the ROMP of DCPD, a reaction less sensitive to small
reactivity differences, the three complexes 2a, 4 and 5 were found
to have similar catalytic properties. A further ROMP was run to
compare catalysts 2a, 2b, and 12, with the results given in FIG.
16.
EXAMPLE 20
ROMP of Dicyclopentadiene (DCPD) using Mixtures of Catalysts 2a and
2b
[0139] Dicyclopentadiene containing 3.5% of tricyclopentadiene (100
g) was polymerized by addition of catalyst
(monomer/catalyst=40,000:1 mole:mole) at 30.degree. C. The
polymerization exotherms for the polymerization catalyzed by
mixtures of catalysts 2a and 2b at various ratios of the catalysts
were measured and are shown in FIG. 17.
[0140] As shown in FIG. 17, the slow isomerization process and
large activity difference between catalysts 2a and 2b allows for
this catalytic system to be tuned by partially isomerizing 2a to a
2a:2b mixture with the desired initiation rate. Indeed, the use of
varying 2a:2b mixtures for the ROMP of DCPD allowed for the control
of the times to exotherm as shown in FIG. 17.
EXAMPLE 21
ROMP of Dicyclopentadiene (DCPD) using Catalysts 2a, 7 and 8
[0141] Dicyclopentadiene containing 3.5% of tricyclopentadiene (100
g) was polymerized by addition of catalyst
(monomer/catalyst=40,000:1 mole:mole) at 30.degree. C. The
polymerization exotherms for the polymerization catalyzed by
catalysts 2a, Ru(Ph-IM) and Ru(Cy-Im) were measured and are shown
in FIG. 18.
[0142] As noted in RCM, catalyst 7 is faster than 2a, while 8 is
slower than 2a. The same trend was observed in the ROMP of DCPD.
These results show that the catalysts that contain an imine ligand
Ru(R-Im) (where R is for instance an alkyl or aryl group) can
easily be tuned by varying the steric and electronic properties of
the R group on the imine.
* * * * *