U.S. patent application number 14/857315 was filed with the patent office on 2016-04-14 for succinic anhydride from ethylene oxide.
The applicant listed for this patent is Novomer, Inc.. Invention is credited to Scott D. Allen, Nye A. Clinton, Bernard Duane Dombek, Olan Stanley Fruchey.
Application Number | 20160102068 14/857315 |
Document ID | / |
Family ID | 45773209 |
Filed Date | 2016-04-14 |
United States Patent
Application |
20160102068 |
Kind Code |
A1 |
Allen; Scott D. ; et
al. |
April 14, 2016 |
SUCCINIC ANHYDRIDE FROM ETHYLENE OXIDE
Abstract
Continuous flow systems and methods produce succinic anhydride
by a double carbonylation of ethylene oxide with carbon monoxide
and at least one catalyst. In some embodiments, the double
carbonylation occurs using a single catalyst. In other embodiments,
a first catalyst is used to promote the first carbonylation, and a
second catalyst different from the first catalyst is used to
promote the second carbonylation. The succinic anhydride is
isolated from the product stream by crystallization and the
catalyst is recycled to the reaction stream.
Inventors: |
Allen; Scott D.; (Ithaca,
NY) ; Dombek; Bernard Duane; (Charleston, WV)
; Fruchey; Olan Stanley; (Hurricane, WV) ;
Clinton; Nye A.; (Hurricane, WV) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Novomer, Inc. |
Ithaca |
NY |
US |
|
|
Family ID: |
45773209 |
Appl. No.: |
14/857315 |
Filed: |
September 17, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13819969 |
Feb 28, 2013 |
9156803 |
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PCT/US2011/049125 |
Aug 25, 2011 |
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14857315 |
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61377917 |
Aug 28, 2010 |
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Current U.S.
Class: |
422/162 ;
422/187 |
Current CPC
Class: |
Y02P 20/584 20151101;
B01J 19/245 20130101; C07D 307/60 20130101; B01J 19/2415 20130101;
B01J 2219/24 20130101 |
International
Class: |
C07D 307/60 20060101
C07D307/60; B01J 19/24 20060101 B01J019/24 |
Claims
1-51. (canceled)
52. A succinic anhydride synthesis system comprising: a carbon
monoxide source; an ethylene oxide source; a solvent source; a
catalyst source; at least one reaction vessel fed with a reaction
stream by the carbon monoxide source, the ethylene oxide source,
the solvent source, and the catalyst source, the reaction stream
comprising carbon monoxide, ethylene oxide, solvent, and catalyst;
wherein the catalyst comprises a transition metal carbonyl compound
and a Lewis acidic co-catalyst; a cooling crystallizer fed from the
at least one reaction vessel; a rotary drum filter fed by the
cooling crystallizer; and a solids dryer fed by the rotary drum
filter.
53. The synthesis system of claim 52, wherein the reaction vessel
comprises a tubular reactor.
54. The synthesis system of claim 52, wherein the reaction vessel
comprises a shell and tube adiabatic reactor.
55. The synthesis system of claim 52, wherein the cooling
crystallizer comprises a feed cooler and a crystallizer flash
drum.
56. The synthesis system of claim 52, wherein the carbon monoxide
source comprises: a methane source; a steam reforming unit fed by
the methane source; a hydrogen pressure swing adsorption unit fed
by the steam reforming unit; a carbon monoxide pressure swing
adsorption unit fed by the hydrogen pressure swing adsorption unit;
a carbon monoxide compressor fed by the carbon monoxide pressure
swing adsorption unit; and a carbon monoxide dryer fed by the
carbon monoxide compressor.
57. The synthesis system of claim 52, wherein the solvent source
comprises: a solvent offloading pump; a solvent dryer fed by the
solvent offloading pump; a solvent storage tank fed by the solvent
dryer; and a solvent charge pump fed by the solvent storage
tank.
58. The synthesis system of claim 52, wherein the catalyst source
comprises a catalyst mix tank and a catalyst charge pump fed by the
catalyst mix tank, wherein the solvent charge pump feeds solvent to
the catalyst mix tank.
59. The synthesis system of claim 52, wherein the cooling
crystallizer is an adiabatic evaporative cooling crystallizer.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims priority to U.S. Provisional
Patent Application Ser. No. 61/377,917, filed Aug. 28, 2010, the
contents of which are herein incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] Acid anhydrides, in particular succinic anhydride, are
valuable reactive intermediates commonly used in a variety of
applications. For example, acid anhydrides are used in copolymers
to produce biodegradable polyesters. Additionally, acid anhydrides
are useful intermediates in organic synthesis because they are
easily ring opened to form diacids or other derivatives. Succinic
anhydride is particularly useful as a precursor to 4 carbon
commodity chemicals such as tetrahydrofuran, gamma butyrolactone
and 1,4-butanediol.
[0003] Previous production methods for acid anhydrides, including
succinic anhydride, included dehydration of corresponding acids or
hydrogenation of maleic anhydride. Additional production methods
include catalyzed carbonylation of alkynes, alkenoic acids and
lactones. Many of the methods suffered from low yield, production
of many byproducts or lacked generality. Novel methods using more
cost effective starting materials are sought.
[0004] U.S. Pat. No. 6,852,865 discloses a class of well-defined
bimetallic catalysts of the general type [Lewis acid]+[M(CO).sub.x]
for the ring-expanding carbonylation of strained heterocycles.
Related catalysts can carbonylate the resulting .beta.-lactones to
succinic anhydrides in high yields while preserving stereochemical
purity. Given the many syntheses of enantiomerically pure epoxides
and the recent advances in epoxide carbonylation to J3-lactones,
subsequent carbonylation of these (3-lactones constitutes a
versatile two-step method for the stereoselective synthesis of
succinic anhydrides. (Scheme 1).
##STR00001##
SUMMARY OF THE INVENTION
[0005] In various aspects, the present invention includes a method
of synthesizing succinic anhydride including the steps of: feeding
a reaction stream including ethylene oxide, at least one catalyst,
at least one solvent, and carbon monoxide to a reaction vessel
under reaction conditions to promote a double carbonylation of
ethylene oxide to form succinic anhydride in the reaction stream in
a continuous flow process; b) treating the reaction stream
containing succinic anhydride to conditions that cause the succinic
anhydride to crystallize such that the reaction stream includes
crystallized succinic anhydride and a liquid phase including
catalyst and solvent; c) separating the crystallized succinic
anhydride from the liquid phase; and d) recycling the catalyst and
the solvent to the reaction stream including the ethylene
oxide.
[0006] In some embodiments, the solvent includes dioxane. In some
embodiments, step b) occurs in an adiabatic evaporative cooling
crystallizer. In some embodiments, step c) occurs in a rotary drum
filter. In some embodiments, step d) includes the substep of
feeding a solution including the catalyst and the solvent to a
recovery flash drum to separate volatiles prior to returning the
solution to the reaction stream. In some embodiments, the method
further includes treating the solution by performing at least one
step selected from the group consisting of: drying the solution;
heating or cooling the solution; removing spent catalyst; adding
solvent; and any combination of two or more of these.
[0007] In some embodiments, the first carbonylation reaction is
performed at a pressure from about 50 psi to about 5000 psi. In
some embodiments, the first carbonylation reaction is performed at
a pressure from about 50 psi to about 2000 psi. In some
embodiments, the first carbonylation reaction is performed at a
pressure from about 200 psi to about 1000 psi. In some embodiments,
the first carbonylation reaction is performed at a pressure from
about 200 psi to about 600 psi.
[0008] In some embodiments, the first carbonylation reaction is
performed at a temperature from about 0.degree. C. to about
125.degree. C. In some embodiments, the first carbonylation
reaction is performed at a temperature from about 30.degree. C. to
about 100.degree. C. In some embodiments, the first carbonylation
reaction is performed at a temperature from about 40.degree. C. to
about 80.degree. C.
[0009] In some embodiments, the at least one catalyst is a single
catalyst. In some embodiments, the single catalyst is
[(ClTPP)Al(THF).sub.2]+[Co(CO).sub.4].sup.-, where ClTPP is
meso-tetra(4-chlorophenyl)porphyrinato and THF is tetrahydrofuran.
In some embodiments, the at least one catalyst includes a first
catalyst selected to promote a first carbonylation of the double
carbonylation and a second catalyst different from the first
catalyst selected to promote a second carbonylation of the double
carbonylation.
[0010] In some embodiments, the catalyst includes a metal carbonyl
compound. In some embodiments, the metal carbonyl compound has the
formula [QM.sub.y(CO).sub.w].sup.x, where: Q is any ligand and need
not be present; M is a metal atom; y is an integer from 1 to 6
inclusive; w is a number such as to provide the stable metal
carbonyl; and x is an integer from -3 to +3 inclusive.
[0011] In some embodiments, M is selected from the group consisting
of Ti, Cr, Mn, Fe, Ru, Co, Rh, Ni, Pd, Cu, Zn, Al, Ga, and In. In
some embodiments, M is Co.
[0012] In some embodiments, the carbonylation catalyst further
includes a Lewis acidic co-catalyst. In some embodiments, the metal
carbonyl compound is anionic, and the Lewis acidic co-catalyst is
cationic. In some embodiments, the metal carbonyl complex includes
a carbonyl cobaltate and the Lewis acidic co-catalyst includes a
metal-centered Lewis acid.
[0013] In some embodiments, the metal-centered Lewis acid is a
metal complex of formula [M'(L).sub.b].sup.c+, where: M' is a
metal; each L is a ligand; b is an integer from 1 to 6 inclusive; c
is 1, 2, or 3; and where, if more than one L is present, each L may
be the same or different. In some embodiments, M' is selected from
the group consisting of: a transition metal, a group 13 or 14
metal, and a lanthanide. In some embodiments, M' is a transition
metal or a group 13 metal. In some embodiments, M' is selected from
the group consisting of aluminum, chromium, indium and gallium. In
some embodiments, M' is aluminum. In some embodiments, M' is
chromium.
[0014] In some embodiments, the Lewis acid includes a dianionic
tetradentate ligand. In some embodiments, the dianionic
tetradentate ligand is selected from the group consisting of:
porphyrin derivatives; salen derivatives;
dibenzotetramethyltetraaza[14]annulene (tmtaa) derivatives;
phthalocyaninate derivatives; and derivatives of the Trost ligand.
In some embodiments step c) includes the substep of filtering the
reaction stream.
[0015] In various aspects, the present invention provides a
succinic anhydride synthesis system including: a carbon monoxide
source; an ethylene oxide source; a solvent source; a catalyst
source; at least one reaction vessel fed with a reaction stream by
the carbon monoxide source, the ethylene oxide source, the solvent
source, and the catalyst source, the reaction stream including
carbon monoxide, ethylene oxide, solvent, and catalyst; an
adiabatic evaporative cooling crystallizer fed from the at least
one reaction vessel; a rotary drum filter fed by the adiabatic
evaporative cooling crystallizer; a solids dryer fed by the rotary
drum filter; and a recovery flash drum fed by the adiabatic
evaporative cooling crystallizer, the rotary drum filter, and the
solids dryer, the recovery flash drum feeding recycled catalyst and
solvent to the reaction stream.
[0016] In some embodiments, the reaction vessel includes a tubular
reactor. In some embodiments, the reaction vessel includes a shell
and tube adiabatic reactor. In some embodiments, the adiabatic
evaporative cooling crystallizer includes a feed cooler and a
crystallizer flash drum.
[0017] In some embodiments, the carbon monoxide source includes: a
methane source; a steam reforming unit fed by the methane source; a
hydrogen pressure swing adsorption unit fed by the steam reforming
unit; a carbon monoxide pressure swing adsorption unit fed by the
hydrogen pressure swing adsorption unit; a carbon monoxide
compressor fed by the carbon monoxide pressure swing adsorption
unit; and a carbon monoxide dryer fed by the carbon monoxide
compressor.
[0018] In some embodiments, the solvent source includes: a solvent
offloading pump; a solvent dryer fed by the solvent offloading
pump; and a solvent storage tank fed by the solvent dryer; and a
solvent charge pump fed by the solvent storage tank.
[0019] In some embodiments, the catalyst source includes a catalyst
mix tank and a catalyst charge pump fed by the catalyst mix tank,
wherein the solvent charge pump feeds solvent to the catalyst mix
tank.
BRIEF DESCRIPTION OF THE DRAWING
[0020] FIG. 1 shows a process flow system for the production of
succinic anhydride from ethylene oxide in one embodiment of the
present invention.
DETAILED DESCRIPTION OF VARIOUS EMBODIMENTS OF THE INVENTION
Definitions
[0021] Definitions of specific functional groups and chemical terms
are described in more detail below. For purposes of this invention,
the chemical elements are identified in accordance with the
Periodic Table of the Elements, CAS version, Handbook of Chemistry
and Physics, 75.sup.th Ed., inside cover, and specific functional
groups are generally defined as described therein. Additionally,
general principles of organic chemistry, as well as specific
functional moieties and reactivity, are described in Organic
Chemistry, Thomas Sorrell, University Science Books, Sausalito,
1999; Smith and March March's Advanced Organic Chemistry, 5.sup.th
Edition, John Wiley & Sons, Inc., New York, 2001; Larock,
Comprehensive Organic Transformations, VCH Publishers, Inc., New
York, 1989; Carruthers, Some Modern Methods of Organic Synthesis,
3.sup.rd Edition, Cambridge University Press, Cambridge, 1987; the
entire contents of each of which are incorporated herein by
reference.
[0022] Certain compounds, as described herein may have one or more
double bonds that can exist as either a Z or E isomer, unless
otherwise indicated. The invention additionally encompasses the
compounds as individual isomers substantially free of other isomers
and alternatively, as mixtures of various isomers, e.g., racemic
mixtures of enantiomers. In addition to the above-mentioned
compounds per se, this invention also encompasses compositions
comprising one or more compounds.
[0023] As used herein, the term "isomers" includes any and all
geometric isomers and stereoisomers. For example, "isomers" include
cis- and trans-isomers, E- and Z-isomers, R- and S-enantiomers,
diastereomers, (D)-isomers, (L)-isomers, racemic mixtures thereof,
and other mixtures thereof, as falling within the scope of the
invention. For instance, a compound may, in some embodiments, be
provided substantially free of one or more corresponding
stereoisomers, and may also be referred to as "stereochemically
enriched."
[0024] The terms "halo" and "halogen" as used herein refer to an
atom selected from fluorine (fluoro, --F), chlorine (chloro, --Cl),
bromine (bromo, --Br), and iodine (iodo, -I). The term "halogenic"
as used herein refers to a compound substituted with one or more
halogen atoms.
[0025] The term "aliphatic" or "aliphatic group", as used herein,
denotes a hydrocarbon moiety that may be straight-chain (i.e.,
unbranched), branched, or cyclic (including fused, bridging, and
spiro-fused polycyclic) and may be completely saturated or may
contain one or more units of unsaturation, but which is not
aromatic. Unless otherwise specified, aliphatic groups contain 1-30
carbon atoms. In certain embodiments, aliphatic groups contain 1-12
carbon atoms. In certain embodiments, aliphatic groups contain 1-8
carbon atoms. In certain embodiments, aliphatic groups contain 1-6
carbon atoms. In some embodiments, aliphatic groups contain 1-5
carbon atoms, in some embodiments, aliphatic groups contain 1-4
carbon atoms, in yet other embodiments aliphatic groups contain 1-3
carbon atoms, and in yet other embodiments aliphatic groups contain
1-2 carbon atoms. Suitable aliphatic groups include, but are not
limited to, linear or branched, alkyl, alkenyl, and alkynyl groups,
and hybrids thereof such as (cycloalkyl)alkyl, (cycloalkenyl)alkyl
or (cycloalkyl)alkenyl.
[0026] The term "heteroaliphatic," as used herein, refers to
aliphatic groups wherein one or more carbon atoms are independently
replaced by one or more atoms selected from the group consisting of
oxygen, sulfur, nitrogen, phosphorus, or boron. In certain
embodiments, one or two carbon atoms are independently replaced by
one or more of oxygen, sulfur, nitrogen, or phosphorus.
Heteroaliphatic groups may be substituted or unsubstituted,
branched or unbranched, cyclic or acyclic, and include
"heterocycle," "heterocyclyl," "heterocycloaliphatic," or
"heterocyclic" groups.
[0027] The term "epoxide", as used herein, refers to a substituted
or unsubstituted oxirane. Substituted oxiranes include
monosubstituted oxiranes, disubstituted oxiranes, trisubstituted
oxiranes, and tetrasubstituted oxiranes. Such epoxides may be
further optionally substituted as defined herein. In certain
embodiments, epoxides comprise a single oxirane moiety. In certain
embodiments, epoxides comprise two or more oxirane moieties.
[0028] The term "acrylate" or "acrylates" as used herein refer to
any acyl group having a vinyl group adjacent to the acyl carbonyl.
The terms encompass mono-, di- and tri-substituted vinyl groups.
Examples of acrylates include, but are not limited to: acrylate,
methacrylate, ethacrylate, cinnamate (3-phenylacrylate), crotonate,
tiglate, and senecioate. Because it is known that cylcopropane
groups can in certain instances behave very much like double bonds,
cyclopropane esters are specifically included within the definition
of acrylate herein.
[0029] The term "polymer", as used herein, refers to a molecule of
high relative molecular mass, the structure of which comprises the
multiple repetition of units derived, actually or conceptually,
from molecules of low relative molecular mass. In certain
embodiments, a polymer is comprised of only one monomer species
(e.g., polyethylene oxide). In certain embodiments, a polymer of
the present invention is a copolymer, terpolymer, heteropolymer,
block copolymer, or tapered heteropolymer of one or more
epoxides.
[0030] The term "unsaturated", as used herein, means that a moiety
has one or more double or triple bonds.
[0031] The term "alkyl," as used herein, refers to saturated,
straight- or branched-chain hydrocarbon radicals derived from an
aliphatic moiety containing between one and six carbon atoms by
removal of a single hydrogen atom. Unless otherwise specified,
alkyl groups contain 1-12 carbon atoms. In certain embodiments,
alkyl groups contain 1-8 carbon atoms. In certain embodiments,
alkyl groups contain 1-6 carbon atoms. In some embodiments, alkyl
groups contain 1-5 carbon atoms, in some embodiments, alkyl groups
contain 1-4 carbon atoms, in yet other embodiments alkyl groups
contain 1-3 carbon atoms, and in yet other embodiments alkyl groups
contain 1-2 carbon atoms. Examples of alkyl radicals include, but
are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl,
iso-butyl, sec-butyl, sec-pentyl, iso-pentyl, tert-butyl, n-pentyl,
neopentyl, n-hexyl, sec-hexyl, n-heptyl, n-octyl, n-decyl,
n-undecyl, dodecyl, and the like.
[0032] The term "carbocycle" and "carbocyclic ring" as used herein,
refers to monocyclic and polycyclic moieties wherein the rings
contain only carbon atoms. Unless otherwise specified, carbocycles
may be saturated, partially unsaturated or aromatic, and contain 3
to 20 carbon atoms. The terms "carbocycle" or "carbocyclic" also
include aliphatic rings that are fused to one or more aromatic or
nonaromatic rings, such as decahydronaphthyl or tetrahydronaphthyl,
where the radical or point of attachment is on the aliphatic ring.
In some embodiments, a carbocyclic groups is bicyclic. In some
embodiments, a carbocyclic group is tricyclic. In some embodiments,
a carbocyclic group is polycyclic. In certain embodiments, the
terms "3- to 14-membered carbocycle" and "C.sub.3-14 carbocycle"
refer to a 3- to 8-membered saturated or partially unsaturated
monocyclic carbocyclic ring, or a 7- to 14-membered saturated or
partially unsaturated polycyclic carbocyclic ring.
[0033] Representative carbocyles include cyclopropane, cyclobutane,
cyclopentane, cyclohexane, bicyclo[2,2,1]heptane, norbornene,
phenyl, cyclohexene, naphthalene, spiro[4.5]decane,
[0034] The term "aryl" used alone or as part of a larger moiety as
in "aralkyl", "aralkoxy", or "aryloxyalkyl", refers to monocyclic
and polycyclic ring systems having a total of five to 20 ring
members, wherein at least one ring in the system is aromatic and
wherein each ring in the system contains three to twelve ring
members. The term "aryl" may be used interchangeably with the term
"aryl ring". In certain embodiments of the present invention,
"aryl" refers to an aromatic ring system which includes, but is not
limited to, phenyl, biphenyl, naphthyl, anthracyl and the like,
which may bear one or more substituents. Also included within the
scope of the term "aryl", as it is used herein, is a group in which
an aromatic ring is fused to one or more additional rings, such as
benzofuranyl, indanyl, phthalimidyl, naphthimidyl, phenantriidinyl,
or tetrahydronaphthyl, and the like. In certain embodiments, the
terms "6- to 10-membered aryl" and "C.sub.6-10 aryl" refer to a
phenyl or an 8- to 10-membered polycyclic aryl ring.
[0035] The terms "heteroaryl" and "heteroar-", used alone or as
part of a larger moiety, e.g., "heteroaralkyl", or
"heteroaralkoxy", refer to groups having 5 to 14 ring atoms,
preferably 5, 6, or 9 ring atoms; having 6, 10, or 14 electrons
shared in a cyclic array; and having, in addition to carbon atoms,
from one to five heteroatoms. The term "heteroatom" refers to
nitrogen, oxygen, or sulfur, and includes any oxidized form of
nitrogen or sulfur, and any quaternized form of a basic nitrogen.
Heteroaryl groups include, without limitation, thienyl, furanyl,
pyrrolyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, oxazolyl,
isoxazolyl, oxadiazolyl, thiazolyl, isothiazolyl, thiadiazolyl,
pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, indolizinyl, purinyl,
naphthyridinyl, benzofuranyl and pteridinyl. The terms "heteroaryl"
and "heteroar-", as used herein, also include groups in which a
heteroaromatic ring is fused to one or more aryl, cycloaliphatic,
or heterocyclyl rings, where the radical or point of attachment is
on the heteroaromatic ring. Nonlimiting examples include indolyl,
isoindolyl, benzothienyl, benzofuranyl, dibenzofuranyl, indazolyl,
benzimidazolyl, benzthiazolyl, quinolyl, isoquinolyl, cinnolinyl,
phthalazinyl, quinazolinyl, quinoxalinyl, 4H-quinolizinyl,
carbazolyl, acridinyl, phenazinyl, phenothiazinyl, phenoxazinyl,
tetrahydroquinolinyl, tetrahydroisoquinolinyl, and
pyrido[2,3-b]-1,4-oxazin-3(4H)-one. A heteroaryl group may be mono-
or bicyclic. The term "heteroaryl" may be used interchangeably with
the terms "heteroaryl ring", "heteroaryl group", or
"heteroaromatic", any of which terms include rings that are
optionally substituted. The term "heteroaralkyl" refers to an alkyl
group substituted by a heteroaryl, wherein the alkyl and heteroaryl
portions independently are optionally substituted. In certain
embodiments, the term "5- to 14-membered heteroaryl" refers to a 5-
to 6-membered heteroaryl ring having 1 to 3 heteroatoms
independently selected from nitrogen, oxygen, or sulfur, or an 8-
to 14-membered polycyclic heteroaryl ring having 1 to 4 heteroatoms
independently selected from nitrogen, oxygen, or sulfur.
[0036] As used herein, the terms "heterocycle", "heterocyclyl",
"heterocyclic radical", and "heterocyclic ring" are used
interchangeably and refer to a stable 5- to 7-membered monocyclic
or 7-14-membered bicyclic heterocyclic moiety that is either
saturated, partially unsaturated, or aromatic and having, in
addition to carbon atoms, one or more, preferably one to four,
heteroatoms, as defined above. When used in reference to a ring
atom of a heterocycle, the term "nitrogen" includes a substituted
nitrogen. As an example, in a saturated or partially unsaturated
ring having 0-3 heteroatoms selected from oxygen, sulfur or
nitrogen, the nitrogen may be N (as in 3,4-dihydro-2H-pyrrolyl), NH
(as in pyrrolidinyl), or +NR (as in N-substituted pyrrolidinyl). In
some embodiments, the term "3- to 14-membered heterocycle" refers
to a 3- to 8-membered saturated or partially unsaturated monocyclic
heterocyclic ring having 1 to 2 heteroatoms independently selected
from nitrogen, oxygen, or sulfur, or a 7- to 14-membered saturated
or partially unsaturated polycyclic heterocyclic ring having 1-3
heteroatoms independently selected from nitrogen, oxygen, or
sulfur.
[0037] A heterocyclic ring can be attached to its pendant group at
any heteroatom or carbon atom that results in a stable structure
and any of the ring atoms can be optionally substituted. Examples
of such saturated or partially unsaturated heterocyclic radicals
include, without limitation, tetrahydrofuranyl, tetrahydrothienyl,
pyrrolidinyl, pyrrolidonyl, piperidinyl, pyrrolinyl,
tetrahydroquinolinyl, tetrahydroisoquinolinyl, decahydroquinolinyl,
oxazolidinyl, piperazinyl, dioxanyl, dioxolanyl, diazepinyl,
oxazepinyl, thiazepinyl, morpholinyl, and quinuclidinyl. The terms
"heterocycle", "heterocyclyl", "heterocyclyl ring", "heterocyclic
group", "heterocyclic moiety", and "heterocyclic radical", are used
interchangeably herein, and also include groups in which a
heterocyclyl ring is fused to one or more aryl, heteroaryl, or
cycloaliphatic rings, such as indolinyl, 3H-indolyl, chromanyl,
phenanthridinyl, or tetrahydroquinolinyl, where the radical or
point of attachment is on the heterocyclyl ring. A heterocyclyl
group may be mono- or bicyclic. The term "heterocyclylalkyl" refers
to an alkyl group substituted by a heterocyclyl, wherein the alkyl
and heterocyclyl portions independently are optionally
substituted.
[0038] As used herein, the term "partially unsaturated" refers to a
ring moiety that includes at least one double or triple bond. The
term "partially unsaturated" is intended to encompass rings having
multiple sites of unsaturation, but is not intended to include aryl
or heteroaryl moieties, as herein defined.
[0039] As described herein, compounds of the invention may contain
"optionally substituted" moieties. In general, the term
"substituted", whether preceded by the term "optionally" or not,
means that one or more hydrogens of the designated moiety are
replaced with a suitable substituent. Unless otherwise indicated,
an "optionally substituted" group may have a suitable substituent
at each substitutable position of the group, and when more than one
position in any given structure may be substituted with more than
one substituent selected from a specified group, the substituent
may be either the same or different at every position. Combinations
of substituents envisioned by this invention are preferably those
that result in the formation of stable or chemically feasible
compounds. The term "stable", as used herein, refers to compounds
that are not substantially altered when subjected to conditions to
allow for their production, detection, and, in certain embodiments,
their recovery, purification, and use for one or more of the
purposes disclosed herein.
[0040] Suitable monovalent substituents on a substitutable carbon
atom of an "optionally substituted" group are independently
halogen; --(CH.sub.2).sub.0-4R.sup..smallcircle.;
--(CH.sub.2).sub.0-4OR.sup..smallcircle.;
--O--(CH.sub.2).sub.0-4C(O)OR.sup..smallcircle.;
--(CH.sub.2).sub.0-4CH(OR.sup..smallcircle.).sub.2;
--(CH.sub.2).sub.0-4SR.sup..smallcircle.; --(CH.sub.2).sub.0-4Ph,
which may be substituted with R.sup..smallcircle.;
--(CH.sub.2).sub.0-4O(CH.sub.2).sub.0-1Ph which may be substituted
with R.sup..smallcircle.; --CH.dbd.CHPh, which may be substituted
with R.sup..smallcircle.; --NO.sub.2; --CN; --N.sub.3;
--(CH.sub.2).sub.0-4N(R.sup..smallcircle.).sub.2;
--(CH.sub.2).sub.0-4N(R.sup..smallcircle.)C(O)R.sup..smallcircle.;
--N(R.sup..smallcircle.)C(S)R.sup..smallcircle.;
--(CH.sub.2).sub.0-4N(R.sup..smallcircle.)C(O)NR.sup..smallcircle..sub.2;
--N(R.sup..smallcircle.)C(S)NR.sup..smallcircle..sub.2;
--(CH.sub.2).sub.0-4N(R.sup..smallcircle.)C(O)OR.sup..smallcircle.;
--N(R.sup..smallcircle.)N(R.sup..smallcircle.)C(O)R.sup..smallcircle.;
--N(R.sup..smallcircle.)N(R.sup..smallcircle.)C(O)NR.sup. .sub.2;
--N(R.sup..smallcircle.)N(R.sup..smallcircle.)C(O)OR.sup..smallcircle.;
--(CH.sub.2).sub.0-4C(O)R.sup..smallcircle.;
--C(S)R.sup..smallcircle.; --(CH.sub.2).sub.0-4C(O)OR;
--(CH.sub.2).sub.0-4C(O)N(R.sup..smallcircle.).sub.2;
--(CH.sub.2).sub.0-4C(O)SR;
--(CH.sub.2).sub.0-4C(O)OSiR.sup..smallcircle..sub.3;
--(CH.sub.2).sub.0-4OC(O)R.sup..smallcircle.;
--OC(O)(CH.sub.2).sub.0-4SR.sup..smallcircle.,
SC(S)SR.sup..smallcircle.;
--(CH.sub.2).sub.0-4SC(O)R.sup..smallcircle.;
--(CH.sub.2).sub.0-4C(O)NR.sup..smallcircle..sub.2;
--C(S)NR.sup..smallcircle..sub.2; --C(S)SR.sup..smallcircle.;
--SC(S)SR.sup..smallcircle.,
--(CH.sub.2).sub.0-4OC(O)NR.sup..smallcircle..sub.2;
--C(O)N(OR.sup. )R.sup..smallcircle.;
--C(O)C(O)R.sup..smallcircle.;
--C(O)CH.sub.2C(O)R.sup..smallcircle.;
--C(NOR.sup..smallcircle.)R.sup..smallcircle.;
--(CH.sub.2).sub.0-4SSR.sup..smallcircle.;
--(CH.sub.2).sub.0-4S(O).sub.2R.sup..smallcircle.;
--(CH.sub.2).sub.0-4S(O).sub.2OR.sup..smallcircle.;
--(CH.sub.2).sub.0-4OS(O).sub.2R.sup..smallcircle.;
--S(O).sub.2NR.sup..smallcircle..sub.2;
--(CH.sub.2).sub.0-4S(O)R.sup..smallcircle.; --N(R.sup.
)S(O).sub.2NR.sup..smallcircle..sub.2;
--N(R.sup..smallcircle.)S(O).sub.2R.sup..smallcircle.;
--N(OR.sup..smallcircle.)R.sup..smallcircle.;
--C(NH)NR.sup..smallcircle..sub.2; --P(O).sub.2R.sup..smallcircle.;
--P(O)R.sup..smallcircle..sub.2; --OP(O)R.sup. .sub.2;
--OP(O)(OR.sup..smallcircle.).sub.2; --SiR.sup..smallcircle..sub.3;
--(C.sub.1-4 straight or branched
alkylene)O--N(R.sup..smallcircle.).sub.2; or --(C.sub.1-4 straight
or branched alkylene)C(O)O--N(R.sup..smallcircle.).sub.2, wherein
each R.sup. may be substituted as defined below and is
independently hydrogen, C.sub.1-8 aliphatic, --CH.sub.2Ph,
--O(CH.sub.2).sub.0-1Ph, or a 5-6-membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, or sulfur, or, notwithstanding the
definition above, two independent occurrences of R.sup. , taken
together with their intervening atom(s), form a 3-12-membered
saturated, partially unsaturated, or aryl mono- or polycyclic ring
having 0-4 heteroatoms independently selected from nitrogen,
oxygen, or sulfur, which may be substituted as defined below.
[0041] Suitable monovalent substituents on R.sup. (or the ring
formed by taking two independent occurrences of R.sup. together
with their intervening atoms), are independently halogen,
--(CH.sub.2).sub.0-2R.sup. , -(haloR.sup. ),
--(CH.sub.2).sub.0-2OH, --(CH.sub.2)O.sub.2OR.sup. ,
--(CH.sub.2).sub.0-2CH(OR.sup. ).sub.2; --O(haloR.sup. ), --CN,
--N.sub.3, --(CH.sub.2).sub.0-2C(O)R.sup. ,
--(CH.sub.2)O.sub.2C(O)OH, --(CH.sub.2)O.sub.2C(O)OR.sup. ,
--(CH.sub.2).sub.0-4C(O)N(R.sup. ).sub.2;
--(CH.sub.2).sub.0-2SR.sup. , --(CH.sub.2)O.sub.2SH,
--(CH.sub.2).sub.0-2NH.sub.2, --(CH.sub.2).sub.0-2NHR.sup. ,
--(CH.sub.2).sub.0-2NR.sup. .sub.2, --NO.sub.2, --SiR.sup. .sub.3,
--OSiR.sup. .sub.3, --C(O)SR.sup. , --(C.sub.1-4 straight or
branched alkylene)C(O)OR.sup. , or --SSR.sup. wherein each R.sup.
is unsubstituted or where preceded by "halo" is substituted only
with one or more halogens, and is independently selected from
C.sub.1-4 aliphatic, --CH.sub.2Ph, --O(CH.sub.2)O.sub.1Ph, or a
5-6-membered saturated, partially unsaturated, or aryl ring having
0-4 heteroatoms independently selected from nitrogen, oxygen, or
sulfur. Suitable divalent substituents on a saturated carbon atom
of R.sup. include .dbd.O and .dbd.S.
[0042] Suitable divalent substituents on a saturated carbon atom of
an "optionally substituted" group include the following: .dbd.O,
.dbd.S, .dbd.NNR*.sub.2, .dbd.NNHC(O)R*, .dbd.NNHC(O)OR*,
.dbd.NNHS(O).sub.2R*, .dbd.NR*, .dbd.NOR*,
--O(C(R*.sub.2)).sub.2-3O--, or --S(C(R*.sub.2)).sub.2-3S--,
wherein each independent occurrence of R* is selected from
hydrogen, C.sub.1-6 aliphatic which may be substituted as defined
below, or an unsubstituted 5-6-membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, or sulfur. Suitable divalent
substituents that are bound to vicinal substitutable carbons of an
"optionally substituted" group include: --O(CR*.sub.2).sub.2-3O--,
wherein each independent occurrence of R* is selected from
hydrogen, C.sub.1 6 aliphatic which may be substituted as defined
below, or an unsubstituted 5-6-membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, or sulfur.
[0043] Suitable substituents on the aliphatic group of R* include
halogen, --R.sup. , -(haloR.sup. ), --OH, --OR.sup. ,
--O(haloR.sup. ), --CN, --C(O)OH, --C(O)OR.sup. , --NH.sub.2,
--NHR.sup. , --NR.sup. .sub.2, or --NO.sub.2, wherein each R.sup.
is unsubstituted or where preceded by "halo" is substituted only
with one or more halogens, and is independently C.sub.1-4
aliphatic, --CH.sub.2Ph, --O(CH.sub.2).sub.0-1Ph, or a 5-6-membered
saturated, partially unsaturated, or aryl ring having 0-4
heteroatoms independently selected from nitrogen, oxygen, or
sulfur.
[0044] Suitable substituents on a substitutable nitrogen of an
"optionally substituted" group include --R.sup..dagger.,
--NR.sub.2.sup..dagger., --C(O)R.sup..dagger.,
--C(O)OR.sup..dagger., --C(O)C(O)R.sup..dagger.,
--C(O)CH.sub.2C(O)R, --S(O).sub.2R.sup..dagger.,
--S(O).sub.2NR.sup..dagger..sub.2, --C(S)NR.sup..dagger..sub.2,
--C(NH)NR.sup..dagger..sub.2, or
--N(R.sup..dagger.)S(O).sub.2R.sup..dagger.; wherein each
R.sup..dagger. is independently hydrogen, C.sub.1-6 aliphatic which
may be substituted as defined below, unsubstituted --OPh, or an
unsubstituted 5-6-membered saturated, partially unsaturated, or
aryl ring having 0-4 heteroatoms independently selected from
nitrogen, oxygen, or sulfur, or, notwithstanding the definition
above, two independent occurrences of R.sup..dagger., taken
together with their intervening atom(s) form an unsubstituted
3-12-membered saturated, partially unsaturated, or aryl mono- or
bicyclic ring having 0-4 heteroatoms independently selected from
nitrogen, oxygen, or sulfur.
[0045] Suitable substituents on the aliphatic group of
R.sup..dagger. are independently halogen, --R.sup. , -(haloR.sup.
), --OH, --OR.sup. , --O(haloR.sup. ), --CN, --C(O)OH,
--C(O)OR.sup. , --NH.sub.2, --NHR.sup. , --NR.sup. .sub.2, or
--NO.sub.2, wherein each R.sup. is unsubstituted or where preceded
by "halo" is substituted only with one or more halogens, and is
independently C.sub.1-4 aliphatic, CH.sub.2Ph,
O(CH.sub.2).sub.0-1Ph, or a 5-6-membered saturated, partially
unsaturated, or aryl ring having 0-4 heteroatoms independently
selected from nitrogen, oxygen, or sulfur.
[0046] As used herein, the term "catalyst" refers to a substance
the presence of which increases the rate of a chemical reaction,
while not being consumed or undergoing a permanent chemical change
itself.
Double Carbonylation
[0047] Methods of the present invention achieve the double
carbonylation of epoxides, whereby each epoxide molecule reacts
with two molecules of carbon monoxide to produce an acid anhydride
(e.g., a cyclic anhydride). The double carbonylation is facilitated
by the catalysts and conditions of the present invention. The
double carbonylation is preferably achieved in a single process
using reaction conditions under which both carbonylation reactions
occur without the necessity of isolating or purifying the product
of the first carbonylation.
##STR00002##
[0048] With known catalysts and conditions, a useful process
according to Scheme 2 has previously been unachievable, since the
two steps (lactone formation from an epoxide and anhydride
formation from a lactone) were found to have different and often
mutually-exclusive reaction requirements. One embodiment of the
present invention encompasses catalyst/solvent combinations that
enable this process to succeed in a single pot reaction format. The
present invention provides catalysts and methods that enable the
double carbonylation of epoxides to provide acid anhydride
products. In some embodiments, the process is a continuous process.
In some embodiments, the acid anhydride product is crystallizable
in order to separate it from the catalyst or catalysts. In one
embodiment, the epoxide is ethylene oxide and the product is
succinic anhydride, although the epoxide may be any epoxide that
forms an acid anhydride derivative that is crystallizable. For
example, the epoxide may be propylene oxide, where the product is
methylsuccinic anhydride.
[0049] The catalysts described herein may be used to successfully
transform epoxides into acid anhydrides in a continuous flow
process. In some embodiments, the transformation occurs in a single
reaction (i.e. in a single reaction vessel under one set of
reaction conditions). The reaction vessel is can be a continuous
flow reaction vessel. In other embodiments, the transformation
occurs under continuous flow using more than one reaction vessel
but without isolation of the intermediate lactone product. In some
embodiments, the double carbonylation occurs using a single
catalyst.
[0050] In some embodiments, the double carbonylation uses a single
catalyst for both carbonylation steps. In some embodiments, two
catalysts are used in which one catalyst is selected for improved
performance in the first carbonylation step and the other is
selected for improved performance in the second carbonylation step.
In other embodiments, a first catalyst is used to promote the first
carbonylation, and a second catalyst different from the first
catalyst is used to promote the second carbonylation. In these
embodiments, the catalysts and solvents are preferably chosen to
optimize the reaction rate of the particular carbonylation
step.
[0051] In some embodiments of the present invention, the
transformation occurs in a single continuous flow reaction vessel
with controlled reaction conditions in the reaction vessel or along
the length of the reaction vessel. In some embodiments, the
reaction conditions as the reaction stream enters the reaction
vessel are different from the reaction conditions as the product
stream leaves the reaction vessel such that the reaction conditions
as the reaction stream enters the reaction vessel promote the first
carbonylation, and the reaction conditions as the product stream
leaves the reaction vessel promote the second carbonylation.
Several aspects of the reaction conditions have been found to
affect the outcome of these processes including, but not limited
to, the presence of a reaction solvent, the concentration of the
substrate, the amount of catalyst present, and the pressure and
temperature at which the reaction is performed.
[0052] FIG. 1 shows a process flow system for the production of
succinic anhydride from ethylene oxide in a preferred embodiment of
the present invention. In this embodiment, the epoxide is
transferred from an epoxide source, (e.g., railcars), by an
offloading pump to a storage tank, where it is stored until needed.
The epoxide is preferably ethylene oxide (EO) in this embodiment.
The solvent, (e.g., dioxane), is transferred from a solvent source
(e.g., trucks), by an offloading pump to a dryer before being
stored in a storage tank. The catalyst is stored in a mix tank.
Carbon monoxide (CO) from a carbon monoxide source is compressed in
a compressor and dried in a dryer. In certain embodiments, the
carbon monoxide, along with hydrogen, is produced by steam
reforming methane from a methane source (e.g., a pipeline). The
hydrogen is separated, for example by pressure swing adsorption
(PSA) and may be used for other purposes, for example butanediol
production. The CO is purified by a further PSA prior to
compression, with carbon dioxide and methane being recycled for
further steam reforming. The solvent is supplied by a charge pump,
which sends a portion of the solvent to the catalyst mix tank to
form a slurry or solution. Where a slurry is produced, it may be
supplied by a charge pump to combine with additional solvent to
form a catalyst-solvent solution. The EO is supplied by a charge
pump, and the CO is applied to the EO prior to mixing with the
catalyst-solvent solution to form the reaction stream. The reaction
stream is fed to a tubular or shell and tube adiabatic reactor with
temperature control.
[0053] The product stream exiting the reactor can then be sent to a
separation process to isolate the acid anhydride product from the
solvent, catalyst, by-products and un-reacted reactants. The
separation can be one step or a combination of steps. Further, the
separation can be a solid-liquid, liquid-liquid or liquid-gas
separation. In one embodiment, the product stream exiting the
reactor is fed to an adiabatic evaporative cooling anhydride
crystallizer including a crystallizer feed cooler followed by a
crystallizer flash drum. This produces a volatiles stream and a
slurry of solid succinic anhydride along with the catalyst in
solvent. The catalyst is preferably highly soluble in the solvent
such that it remains dissolved in the slurry. In one embodiment,
the slurry is fed to a solvent/catalyst recovery rotary drum
filter, where the liquid solution is separated from the solid
succinic anhydride. The solid succinic anhydride stream is sent to
a succinic anhydride solids dryer, which is preferably a rotary
kiln, from which it exits as the product. The volatiles stream from
the crystallizer flash drum is cooled and the remaining gaseous
phase is sent to a solids dryer gas heater, where it is dried and
heated prior to being sent to the succinic anhydride solids dryer
for drying the succinic anhydride. The gas stream exiting the
succinic anhydride solids dryer is sent to a gas cooler prior to
being fed to a solvent/catalyst recovery flash drum along with the
liquid component of the cooled volatiles stream and the liquid
solution exiting the dioxane/catalyst recovery rotary drum filter.
The solvent/catalyst liquid exiting the recovery flash drum is sent
by a recovery pump to the reaction stream before entering the
reactor. The gas stream exiting the recovery flash drum is vented
in part and compressed in part in a compressor and recycled back
into the CO feed stream.
Epoxides & Reactants
[0054] The methods are generally applicable and a wide range of
epoxide starting materials can be used. The epoxide substrates (and
by extension the lactone intermediates and anhydride products) may
be unsubstituted (i.e., ethylene oxide) or may be monosubstituted,
vicinally disubstituted (either cis or trans). The methods can also
be applied to geminally disubstituted, trisubstituted or
tetrasubstituted epoxides though these substrates react more slowly
and tend to give lower yields of anhydride. The substituent(s) on
the epoxide can be any that is compatible with the reaction
conditions described herein.
[0055] In certain embodiments, the epoxide has the formula I:
##STR00003##
[0056] The R group and any other chemical variable appearing in the
Schemes and structures described herein encompass those chemical
moieties and functional groups that would be recognized by one
having skill in the art of organic chemistry as being compatible
with the structure and function of the molecules bearing those
chemical variables. Exemplary functional groups include substituted
and unsubstituted cyclic and acyclic hydrocarbon moieties,
substituted and unsubstituted cyclic and acyclic
heteroatom-containing moieties, as well as common functional groups
comprising heteroatoms, halogens, and metalloid elements. To
further define the range of suitable groups certain definitions are
provided below. Nonetheless, it is to be understood that these
definitions are meant to be representative and the absence of a
specific group or moiety in the definitions below is not
necessarily meant to exclude such groups or to imply that such a
group is not encompassed by the present invention.
[0057] In any case where a chemical variable is shown attached to a
bond that crosses a bond of ring (for example as shown for R above,
R.sup.d in certain ligands below, etc.), this means that one or
more such variables are optionally attached to the ring having the
crossed bond. Each R group on such a ring can be attached at any
suitable position, this is generally understood to mean that the
group is attached in place of a hydrogen atom on the parent ring.
This includes the possibility that two R groups can be attached to
the same ring atom. Furthermore, when more than one R group is
present on a ring, each may be the same or different than other R
groups attached thereto, and each group is defined independently of
other groups that may be attached elsewhere on the same molecule,
even though they may be represented by the same identifier.
[0058] In one embodiment of the epoxides of formula I, each R group
can be independently selected from the group consisting of: (a)
C.sub.1 to C.sub.20 alkyl; (b) C.sub.2 to C.sub.20 alkenyl; (c)
C.sub.2 to C.sub.20 alkynyl; (d) up to a C.sub.12 carbocyclc; (c)
up to a C.sub.12 heterocycle; (f) C(R.sup.13).sub.zH.sub.(3-z); and
(g) a polymer chain. Two or more R groups may be taken together
with the carbon atoms to which they are attached to form one or
more rings, and any of (a) through (c) may optionally be further
substituted with one or more F groups.
[0059] F at each occurrence can be independently selected from the
group consisting of: halogen; --OR.sup.10; --OC(O)R.sup.13;
--OC(O)OR.sup.13; --OC(O)NR.sup.11R.sup.12; --CN; --CNO;
--C(O)R.sup.13; --C(O)OR.sup.13; --C(O)NR.sup.11R.sup.12;
--C(R.sup.13).sub.zH.sub.(3-z); --NR.sup.11C(O)R.sup.1;
--NR.sup.11C(O)OR.sup.10; --NCO; --NR.sup.12SO.sub.2R.sup.13;
--S(O).sub.xR.sup.13; --S(O).sub.2NR.sup.11R.sup.12; --NO.sub.2;
--N.sub.3; --(CH.sub.2).sub.kR.sup.14;
--(CH.sub.2).sub.k--Z--R.sup.16; and
--(CH.sub.2).sub.k--Z--(CH.sub.2).sub.m--R.sup.14.
[0060] R.sup.10 at each occurrence can be independently selected
from the group consisting of: --C(R.sup.13).sub.zH.sub.(3-z);
C.sub.1 to C.sub.12 alkyl; C.sub.2 to C.sub.12 alkenyl; C.sub.2 to
C.sub.12 alkynyl; up to a C.sub.12 carbocycle; up to a C.sub.12
heterocycle; --S(O).sub.2R.sup.13; --Si(R.sup.15).sub.3; --H; and a
hydroxyl protecting group.
[0061] R.sup.11 and R.sup.12 at each occurrence can be
independently selected from the group consisting of: --H; C.sub.1
to C.sub.12 alkyl; C.sub.2 to C.sub.12 alkenyl; C.sub.2 to C.sub.12
alkynyl; and --C(R.sup.13).sub.zH.sub.(3-z). R.sup.11 and R.sup.12;
when both present, can optionally be taken together with the atom
to which they are attached to form a 3- to 10-membered ring.
[0062] R.sup.13 at each occurrence can be independently selected
from the group consisting of: --H; C.sub.1 to C.sub.12 alkyl;
C.sub.2 to C.sub.12 alkenyl; C.sub.2 to C.sub.12 alkynyl; up to a
C.sub.12 carbocycle; and up to a C.sub.12 heterocycle.
[0063] R.sup.14 at each occurrence can be independently selected
from the group consisting of: halogen; --OR.sup.10;
--OC(O)R.sup.13; --OC(O)OR.sup.13; --OC(O)NR.sup.11R.sup.12; --CN;
--CNO; --C(R.sup.13).sub.zH.sub.(3-z); --C(O)R.sup.13;
--C(O)OR.sup.13; --C(O)NR.sup.11R.sup.12; --NR.sup.11C(O)R.sup.13;
--NR.sup.11C(O)OR.sup.10; --NR.sup.11SO.sub.2R.sup.13; --NCO;
--N.sub.3; --NO.sub.2; --S(O).sub.xR.sup.13;
--SO.sub.2NR.sup.11R.sup.12; up to a C.sub.12 heterocycle; and up
to a C.sub.12 carbocycle.
[0064] R.sup.15 at each occurrence can be independently selected
from the group consisting of: C.sub.1 to C.sub.6 alkyl; C.sub.2 to
C.sub.6 alkenyl; C.sub.2 to C.sub.6 alkynyl; and up to C.sub.12
substituted or unsubstituted carbocycle.
[0065] R.sup.16 at each occurrence can be independently selected
from the group consisting of: C.sub.1 to C.sub.12 alkyl; C.sub.2 to
C.sub.12 alkenyl; C.sub.2 to C.sub.12 alkynyl; up to a C.sub.12
heterocycle; up to a C.sub.12 carbocycle; and
--C(R.sup.13).sub.zH.sub.(3-z).
[0066] Z is a divalent linker and can be selected from the group
consisting of: --(CH.dbd.CH).sub.a--; --(CH.ident.CH).sub.a--;
--C(O)--; --C(.dbd.NOR.sup.11)--; --C(.dbd.NNR.sup.11R.sup.12)--;
--O--; --N(R.sup.11)--; --N(C(O)R.sup.13)--; --S(O)--; a polyether;
and a polyamine.
[0067] a can be 1, 2, 3, or 4.
[0068] k can be an integer from 1 to 8 inclusive.
[0069] m can be an integer from 1 to 8 inclusive.
[0070] x can be 0, 1, or 2.
[0071] z can be 1, 2, or 3.
[0072] It is to be understood that the present invention
encompasses the use of epoxides which comprise any combination of
these variable definitions. For example, as discussed in below, we
have applied the methods to the following representative
unsubstituted and monosubstituted epoxides: ethylene oxide (4),
propylene oxide (6), 1,2-epoxybutane (8); 1,2-epoxyhexane (10);
1,2-epoxydodecane (12); cyclohexyl oxirane (14); n-butyl glycidyl
ether (16); tert-butyldimethylsilyl glycidyl ether (18); benzyl
glycidyl ether (20); 10,11-epoxyundecan-1-ol (22); 4,5-epoxypentyl
butyrate (24); 5,6-epoxyhexanenitrile (26);
N,N-dimethyl-10,11-undecylamide (28); 1,2-epoxy-5-hexene (30);
1,2-epoxy-7-octene (32); (2,3-epoxypropyl)benzene (34); styrene
oxide (36); and 1,2,7,8-diepoxyoctane (38). Ethylene oxide (4) and
propylene oxide (6) are of particular commercial interest.
[0073] As discussed below, we have also applied the methods to the
following representative disubstituted epoxides:
cis-2,3-epoxybutane (40); trans-2,3-epoxybutane (42);
trans-3,4-epoxyhexane (44); and trans-2,3-epoxyoctane (46).
[0074] As discussed below, we have also applied the methods to the
following representative enantiomerically enriched epoxides:
(R)-propylene oxide ((R)-6); (S)-1,2-epoxyhexane ((S)-10); and
(R)-benzyl glycidyl ether ((R)-20).
[0075] These representative epoxides demonstrate that the methods
are applicable to a range of substituted epoxide substrates
including those containing ethers, alcohols, esters, amides,
nitriles, silyl ethers, alkenes and aromatics. It is to be
understood that these lists are not exhaustive, other functional
groups can also be present, for example ketone and acetal
substituted epoxides have been successfully employed.
[0076] Additional reactants can include carbon monoxide, or a
mixture of carbon monoxide and another gas. In some embodiments,
carbon monoxide is provided in a mixture with hydrogen (e.g.,
Syngas). The ratio of carbon monoxide and hydrogen can be any
ratio, including by not limited to 1:1, 1:2, 1:4, 1:10, 10:1, 4:1,
or 2:1. In some embodiments, the carbon monoxide is provided in a
mixture containing other gases. The carbon monoxide sources include
but are not limited to: wood gas, producer gas, coal gas, town gas,
manufactured gas, hygas, Dowson gas or water gas, among others. In
some embodiments, the carbon monoxide is provided by steam
reforming from another hydrocarbon (e.g., methane) as described
above. The carbon monoxide can be purified by pressure swing
absorption to reduce the quantity of other gases in the steam
reforming effluent. In some embodiments, the carbon monoxide is
provided at super-atmospheric pressure. The quantity of carbon
monoxide should be supplied to effect efficient conversion of the
epoxide starting material to an acid anhydride.
Catalysts
[0077] The present invention encompasses the use of carbonylation
catalysts comprising a Lewis acid in combination with a transition
metal carbonyl complex. The term Lewis acid as used herein refers
to any electrophilic species that is capable of accepting an
electron pair and that is not a Bronsted-Lowry acid.
[0078] In certain embodiments, the catalyst comprises a complex of
formula [Lewis acid].sup.u+{[QT(CO).sub.v].sup.s-}.sup.t where Q is
any ligand and need not be present; T is a transition metal; u is
an integer from 1 to 6 inclusive; s is an integer from 1 to 4
inclusive; t is a number such that t multiplied by s equals u; and
v is an integer from 1 to 9 inclusive. For example, in one
embodiment u and s are both 1. In another embodiment u and s are
both 2. In certain embodiments, v is an integer from 1 to 4
inclusive. In one embodiment, v is 4.
Lewis Acids
[0079] In certain embodiments, the Lewis acid portion of the
catalyst includes an element from groups 3 through 14 of the
periodic table or contains a lanthanide metal. Useful Lewis acids
may either be neutral (e.g., compounds such as AlCl.sub.3,
CrCl.sub.2, CrCl.sub.3, ZnCl.sub.2, BF.sub.3, BCl.sub.3,
Yb(OTf).sub.3, FeCl.sub.2, FeCl.sub.3, CoCl.sub.2, etc.) or
cationic (for instance, metal complexes of the formula
[M(L).sub.b].sup.c+ where M is a metal, each L is a ligand, b is an
integer from 1 to 6 inclusive, and c is 1, 2, or 3, and where, if
more than one L is present, each L may be the same or different). A
broad array of metallo Lewis acids have been found applicable to
the present invention. In certain embodiments, M is a transition
metal, a group 13 or 14 metal, or a lanthanide. Transition metals
and group 13 metals are of particular interest. For example, in
certain embodiments, M is aluminum, chromium, indium or gallium. In
some embodiments, M is aluminum or chromium.
[0080] Similarly, a range of ligands (L) can be present in the
metallo Lewis acid component of the catalyst. In certain
embodiments the ligand can be a dianionic tetradentate ligand.
[0081] Suitable ligands include, but are not limited to: porphyrin
derivatives 1, salen derivatives 2,
dibenzotetramethyltetraaza[14]annulene (tmtaa) derivatives 3,
phthalocyaninate derivatives 4, and derivatives of the Trost ligand
5. In certain embodiments, porphyrin, salen and tmtaa derivatives
are of particular utility. In some cases, a mixture of more than
one Lewis acid component can be present in the catalyst. Exemplary
definitions for the R groups appearing in structures 1 through 5
are more fully described below.
[0082] In certain embodiments, the metal complex includes a metal M
and a ligand L of formula 1:
##STR00004##
[0083] where R.sup.d at each occurrence is independently selected
from the group consisting of: --H; C.sub.1-C.sub.12 alkyl;
C.sub.2-C.sub.12 alkenyl; C.sub.2-C.sub.12 alkynyl; halogen;
--OR.sup.10; --OC(O)R.sup.13; --OC(O)OR.sup.13;
--OC(O)NR.sup.11R.sup.12; --CN; --CNO; --C(O)R.sup.13;
--C(R.sup.13).sub.zH.sub.(3-z); --C(O)OR.sup.13;
C(O)NR.sup.11R.sup.12; --NR.sup.11R.sup.12;
--NR.sup.11C(O)R.sup.10; --NR.sup.11C(O)OR.sup.13;
--NR.sup.11SO.sub.2R.sup.13; --NCO; --N.sub.3; --NO.sub.2;
--S(O).sub.xR.sup.13; --SO.sub.2NR.sup.11R.sup.12;
--C(R.sup.13).sub.zH.sub.(3-z); --(CH.sub.2).sub.kR.sup.14;
--(CH.sub.2).sub.k--Z--R.sup.16; and
--(CH.sub.2).sub.k--Z--(CH.sub.2).sub.m--R.sup.14, and
[0084] where R.sup.10, R.sup.11, R.sup.12, R.sup.13, R.sup.14,
R.sup.16, Z, k, m, x, and z are as defined above.
[0085] In certain embodiments, the metal complex includes a metal M
and a ligand L of formula 2:
##STR00005##
[0086] where R.sup.1 and R.sup.1' are independently selected from
the group consisting of: --H; C.sub.1 to C.sub.12 alkyl; C.sub.2 to
C.sub.12 alkenyl; C.sub.2 to C.sub.12 alkynyl;
--C(R.sup.13).sub.zH.sub.(3-z); --(CH.sub.2).sub.kR.sup.14; and
--(CH.sub.2).sub.k--Z--R.sup.14,
[0087] where R.sup.2, R.sup.2', R.sup.3, and R.sup.3' are
independently selected from the group consisting of: (i)
C.sub.1-C.sub.12 alkyl; (ii) C.sub.2-C.sub.12 alkenyl; (iii)
C.sub.2-C.sub.12 alkynyl; (iv) up to a C.sub.12 carbocyclc; (v) up
to a C.sub.12 heterocycle; (vi) --(CH.sub.2).sub.kR.sup.14; (vii)
R.sup.20; and (viii) --C(R.sup.13).sub.zH.sub.(3-z),
[0088] where each of (i) through (v) may optionally be further
substituted with one or more R.sup.20 groups; and where R.sup.2 and
R.sup.3, and R.sup.2' and R.sup.3' may optionally be taken together
with the carbon atoms to which they are attached to form one or
more rings which may in turn be substituted with one or more
R.sup.20 groups; and
[0089] where R.sup.4 is selected from the group consisting of:
##STR00006## [0090] where X is a divalent linker selected from the
group consisting of: --N(R.sup.11)--; --O--; --S(O).sub.x--;
--(CH.sub.2).sub.k--; --C(O)--; --C(.dbd.NOR.sup.10)--;
--C(R.sup.c).sub.2--; a polyether; a C.sub.3 to C.sub.8 substituted
or unsubstituted carbocycle; and a C.sub.1 to C.sub.8 substituted
or unsubstituted heterocycle, [0091] where R.sup.d is as defined
above, [0092] where R.sup. at each occurrence is independently
selected from the group consisting of: (a) C.sub.1-C.sub.12 alkyl;
(b) C.sub.2-C.sub.12 alkenyl, (c) C.sub.2-C.sub.12 alkynyl; (e) up
to a C.sub.12 carbocycle, (f) up to a C.sub.12 heterocycle; (g)
R.sup.20; (h) --C(R.sup.13).sub.zH.sub.(3-z); and (i) --H, [0093]
where two or more R.sup.c groups may be taken together with the
carbon atoms to which they are attached to form one or more rings,
[0094] where when two R.sup.c groups are attached to the same
carbon atom, they may be taken together to form a moiety selected
from the group consisting of: a 3- to 8-membered spirocyclic ring;
a carbonyl (C.dbd.O), an oxime (C.dbd.NOR.sup.10); a hydrazone
(C.dbd.NNR.sup.11R.sup.12); an imine (C.dbd.NR.sup.11); and an
alkenyl group (C.dbd.CR.sup.11R.sup.12), and [0095] where any of
(a) through (f) may optionally be further substituted with one or
more R.sup.20 groups,
[0096] where R.sup.20 at each occurrence is independently selected
from the group consisting of: --H; halogen; --OR.sup.10;
--OC(O)R.sup.13; --OC(O)OR.sup.13; --OC(O)NR.sup.11R.sup.12; --CN;
--CNO; --C(O)R.sup.13; --C(O)OR.sup.13; --C(O)NR.sup.11R.sup.12;
--C(R.sup.13).sub.zH.sub.(3-z); --NR.sup.11R.sup.12;
--NR.sup.11C(O)R.sup.10; --NR.sup.11C(O)OR.sup.10; --NCO;
--NR.sup.12SO.sub.2R.sup.13; --S(O).sub.xR.sup.13;
--S(O).sub.2NR.sup.11R.sup.12; --NO.sub.2; --N.sub.3;
--(CH.sub.2).sub.kR.sup.14; --(CH.sub.2).sub.k--Z--R.sup.16; and
(CH.sub.2).sub.k--Z--(CH.sub.2).sub.m--R.sup.14, and
[0097] where R.sup.10, R.sup.11, R.sup.12, R.sup.13, R.sup.14,
R.sup.16, Z, k, m, x, and z are as defined above.
[0098] In certain embodiments, the metal complex includes a metal M
and a ligand L of formula 3:
##STR00007##
[0099] where R.sup.d is as defined above,
[0100] where R.sup.1 at each occurrence is independently selected
from the group consisting of: --H; C.sub.1 to C.sub.12 alkyl;
C.sub.2 to C.sub.12 alkenyl; C.sub.2 to C.sub.12 alkynyl;
--C(R.sup.13).sub.zH.sub.(3-z); --(CH.sub.2).sub.kR.sup.14; and
--(CH.sub.2).sub.k--Z--R.sup.14, and
[0101] where R.sup.13, R.sup.14, Z, k, and z are as defined
above.
[0102] In certain embodiments, the metal complex includes a metal M
and a ligand L of formula 4:
##STR00008##
[0103] where R.sup.d is as defined above.
[0104] In certain embodiments, the metal complex includes a metal M
and a ligand L of formula 5:
##STR00009##
[0105] where R.sup.c and R.sup.d are as defined above.
Transition Metal Carbonyl Complexes
[0106] The transition metal carbonyl complex included in the
catalyst may be neutral or anionic. In certain embodiments, the
metal carbonyl complex is anionic, e.g., monoanionic carbonyl
complexes of metals from groups 5, 7 or 9 of the periodic table or
dianionic carbonyl complexes of metals from groups 4 or 8 of the
periodic table. In certain embodiments, the metal carbonyl complex
contains a metal from groups 7 or 9 of the periodic table, e.g.,
cobalt, manganese or rhodium. Examples of suitable anionic metal
carbonyl complexes include, but are not limited to:
[Co(CO).sub.4].sup.- and [Mn(CO).sub.5].sup.-. In certain
embodiments [Co(CO).sub.4].sup.- may be used. In some cases, a
mixture of two or more transition metal carbonyl complexes can be
present in the catalyst.
[0107] While the metal carbonyl complexes disclosed herein are
generally binary metal carbonyl complexes (i.e., they have the
formula M(CO) and consist only of a metal and carbonyl ligands)
this is not a limiting requirement of the present invention, and
the use of mixed ligand metal carbonyl complexes is also
contemplated. For example, a bidentate phosphine ligand may be
present along with the carbonyl ligands. It is also anticipated
that under some reaction conditions, mixed ligand carbonyl
complexes may be formed in situ from the binary complexes during
the reaction. Whether added or formed in situ, catalysts containing
mixed ligand carbonyl complexes are encompassed by the present
invention.
[0108] The stoichiometry of the Lewis acid and the metal carbonyl
complex components of the catalyst encompassed by the present
invention can be varied. Typically, the two components are present
in a ratio that balances the charges of the two species. For
example, if the Lewis acid is a monocation and the metal carbonyl
complex is a dianion, then they can be present in a
charge-balancing ratio of 2:1 (i.e., 2 [Lewis
acid].sup.++[M(CO).sub.x].sup.2-). In some cases, if the charge of
the carbonyl complex exceeds that of the Lewis acid
component-either because there is a stoichiometric excess of the
former, or because the Lewis acid is a neutral species-then the
excess negative charge of the carbonyl complex can be balanced by
the presence of a group 1 or 2 metal cation, or by a non-metallic
cation such as an ammonium, phosphonium, or arsonium cation.
[0109] In some cases, the metal atom of the metallo Lewis acid can
be coordinated to one or more additional neutral coordinating
ligands (for instance to satisfy the metal atom's coordination
valence) one such ligand that is particularly preferred is
tetrahydrofuran (THF), it will be understood however that many
other solvents and other ligands such as are well known in the art
may also fulfill this role without departing from the present
invention. It will also be realized that under reaction conditions,
the coordinating ligands can be replaced by reagents, products,
intermediates or solvents that may be present. Such in
situ-generated species are also encompassed by the present
invention. As with many catalytic processes, the structure of the
specific catalyst added to the reaction will not always be the
active species.
[0110] In a related vein, catalysts suitable for the processes of
the present invention can be formed in situ from individual
components. For example, the Lewis acid and the metal carbonyl
complex can be added separately to the reaction vessel in which the
reaction is performed. In one specific example of this, instead of
adding aluminum tetrakis-(4-chlorophenyl)-porphine
bis-tetrahydrofuran tetracarbonylcobaltate (Ic) as the catalyst,
one can separately add aluminum tetrakis-(4-chlorophenyl)-porphine
chloride and sodium tetracarbonyl cobaltate. In a similar
procedure, an aluminum porphyrin tetrafluoroborate compound
(TPP(Al).sup.+BF.sub.4.sup.-) was combined in situ with
bis(triphenylphosphine)iminium tetracarbonyl cobaltate
(PPN.sup.+Co(CO).sub.4.sup.-) to provide the active catalyst. It is
thus to be understood that such combinations of reagents that will
produce a Lewis acid/metal carbonyl pair in situ are within the
scope of the present invention.
[0111] Without wishing to be bound by any theory or to thereby
limit the scope of the invention, it is believed that catalysts
combining a Lewis acid component that is cationic and a metal
carbonyl complex that is anionic are particularly suitable for
carbonylation processes of the present invention. It is further
believed that Lewis acid/metal carbonyl combinations that have a
propensity to form non-ionic associations may be less effective
(for instance if a covalent or coordinate covalent bond is prone to
form between the metals of the two components). In such cases it
can be advantageous to add additional components that prevent this
association. As one example, when the Lewis acid component is based
on an indium porphyrin complex, and the metal carbonyl component is
tetracarbonyl cobaltate, the carbonylation reaction is improved by
addition of triphenylphosphine. Again without being bound by theory
or thereby limiting the scope of the present invention, the
phosphine is believed to coordinate with the indium and thereby
disrupt its propensity to bind to the cobaltate component of the
catalyst.
[0112] In some cases, it has been found advantageous to have an
excess of the transition metal carbonyl component of the catalyst
present in the reaction mixture. For instance, the metal carbonyl
complex can be present in an excess ranging from about 2-fold to
about 10-fold. If there is an excess of an anionic metal carbonyl
complex relative to the Lewis acid, then the negative charge can be
balanced as described above, the excess negative charge is balanced
by the presence of an alkali or alkaline earth metal.
[0113] Solvents
[0114] With respect to solvents (i.e., reaction solvents), methods
of the invention have been found to be improved by the presence of
a solvent. In some embodiments, solvents are of a low to moderate
polarity. In some embodiments, the solvent fully dissolves the
epoxide substrate to provide a reaction mixture in which the
catalyst employed is at least partially soluble. Additionally, in
some aspect, the solvents lack reactive functional groups.
[0115] In some embodiments, the solvent includes a Lewis base. The
term Lewis base as used herein refers to any nucleophilic species
that is capable of donating an electron pair. In some embodiments,
the presence of suitable solvents can suppress the formation of
polymeric side products and, in some cases, increase the rate
and/or yield of the reaction.
[0116] In certain embodiments, the Lewis base is distinct from the
epoxide. In other embodiments, the Lewis base is the epoxide (i.e.,
the reaction is performed in neat epoxide). Indeed, while the use
of non-epoxide solvents may lead to higher yields, we have found
that certain catalysts allow double carbonylation to be achieved in
neat epoxide.
[0117] In certain embodiments, the solvent used will fully dissolve
the epoxide and provide a reaction mixture in which the catalyst
employed is at least partially soluble. Suitable solvents may
include ethers, ketones, aromatic hydrocarbons, halocarbons,
esters, nitriles, and some alcohols. For example, without
limitation, a suitable solvent may include: 1,4-dioxane;
1,3-dioxane; tetrahydrofuran; tetrahydropyran; dimethoxyethane;
glyme; diethyl ether; t-butyl methyl ether; 2,5-dimethyl
tetrahydrofuran; ethyl acetate; propyl acetate; butyl acetate;
acetone; 2-butanone; cyclohexanone; toluene; acetonitrile; and
difluorobenzene. In some embodiments, the solvent includes
1,4-dioxane, toluene, and/or dimethoxyethane. In one embodiment,
solvent includes 1,4-dioxane. Mixtures of two or more of the above
solvents are also useful, and in some cases may be preferred to a
single solvent. For example, mixtures of toluene and 1,4-dioxane
are useful.
[0118] In certain embodiments, we have found that Lewis bases of
low to moderate polarity improve the performance of the reaction
over polar solvents. Thus, in certain embodiments, the solvent may
include a Lewis base which is less polar than 1,3-dioxane
(.di-elect cons.=dielectric constant at 20 C=13.6). In certain
embodiments, the solvent includes a Lewis base which is less polar
than ortho-difluorobenzene (.di-elect cons.=13). In certain
embodiments, the solvent includes a Lewis base which is less polar
than meta-difluorobenzene (.di-elect cons.=5). In certain
embodiments, the solvent includes a Lewis base with substantially
the same polarity as 1,4-dioxane (.di-elect cons.=2.2).
[0119] In certain embodiments, we have found that Lewis bases of
low to moderate electron donicity improve the performance of the
reaction over strongly donating Lewis bases. Thus, in certain
embodiments, the solvent may include a Lewis base with lower
electron donicity than tetrahydrofuran. In certain embodiments, the
solvent may include a Lewis base with lower electron donicity than
2-methyltetrahydrofuran. In certain embodiments, the solvent may
include a Lewis base with lower electron donicity than
2,5-dimethyltetrahydrofuran. In certain embodiments, the solvent
may include a Lewis base with higher electron donicity than
difluorobenzene. In certain embodiments, the solvent may include a
Lewis base with higher electron donicity than toluene. In certain
embodiments, the solvent may include a Lewis base with
substantially the same electron donicity as 1,4-dioxane.
[0120] It will be appreciated that while 1,4-dioxane appears to
produce particularly high yields of anhydride when used in
combination with various catalysts that are described in the
Examples, other solvents and mixtures of solvents (including
solvents and mixtures that are not explicitly disclosed) may be
used with these catalysts. While some of these combinations may
produce lower yields they remain within the scope of the present
invention. It will also be appreciated that present invention is in
no way limited to the representative catalysts that are exemplified
in this application. In particular, now that we have demonstrated
that high yield double carbonylation is possible through
appropriate selection of catalyst and solvent, those skilled in the
art will recognize that our teachings can be generalized to other
catalyst/solvent combinations.
[0121] In general, highly polar, reactive or protic solvents are
generally inferior or unsuitable for processes of the present
invention. Inferior solvents include ionic liquids, chlorinated
hydrocarbons, sulfolane, dimethylsulfoxide, formamide, pyridine,
and the like.
[0122] The solvent is preferably added in an amount sufficient to
achieve an epoxide concentration of from about 0.1M to about 20M,
for example from about 0.1M to about 5M or about from 0.5M to about
2M.
[0123] Reaction Conditions
[0124] The conditions for the carbonylation reaction are selected
based on a number of factors to effect conversion of the epoxide to
an acid anhydride. Temperature, pressure, and reaction time
influence reaction speed and efficiency. Additionally, the ratio of
reactants to each other and to the catalyst effect reaction speed
and efficiency.
[0125] In some embodiments, the reaction temperature can range from
between about -20.degree. C., to about 600.degree. C. In some
embodiments, the reaction temperature is about -20.degree. C.,
about 0.degree. C., about 20.degree. C., about 40.degree. C., about
60.degree. C., about 80.degree. C., about 100.degree. C., about
200.degree. C., about 300.degree. C., about 400.degree. C., about
500.degree. C. or about 600.degree. C. In some embodiments, the
reactants, catalyst and solvent are supplied to the reactor at
standard temperature, and then heated in the reactor. In some
embodiments, the reactants are pre-heated before entering the
reactor. In some embodiments, the reactants are cooled before
entering the reactor.
[0126] Turning next to the effect of temperature, in certain
embodiments the reaction temperature was found to affect the rate
and outcome of processes of the invention. At higher temperatures
the reaction proceeds more quickly than at lower temperatures, but
the propensity to form reaction by-products may increase.
[0127] In some embodiments, the reaction pressure can range from
between about 50 psig to about 5000 psig. In some embodiments, the
reaction pressure is about 100 psig, about 200 psig, about 300
psig, about 400 psig, about 500 psig, about 600 psig, about 700
psig, about 800 psig, about 900 psig, or about 1000 psig. In some
embodiments, the pressure ranges from about 50 psig to about 2000
psig. In some embodiments, the pressure ranges from about 100 psig
to 1000 psig. In some embodiments, the pressure ranges from about
200 psig to about 800 psig. In some embodiments, the reaction
pressure is supplied entirely by the carbon monoxide. For example,
the reactants, catalyst and solvent are charged to the reactor at
atmospheric pressure, or under a vacuum, and carbon monoxide is
added to the reactor to increase pressure to the reaction pressure.
In some embodiments, all reactants, solvent and catalyst are
supplied to the reactor at reaction pressure.
[0128] Optionally, the atmosphere under which the reaction is
conducted can include other gasses. Such other gasses can include,
for example, hydrogen, methane, nitrogen, carbon dioxide, air, and
trace amounts of steam. The present invention also specifically
encompasses processes in which other carbon monoxide-containing gas
streams provide the atmosphere under which the reaction is
conducted, as described above. Undesirable side-product can be
minimized at higher reaction temperatures by performing the
reaction at relatively high carbon monoxide pressures. In some
cases therefore, the optimal temperature will be dependent upon the
pressure at which the reaction is conducted. At high carbon
monoxide pressures, e.g., greater than about 400 psi, elevated
temperatures were found to be advantageous for the reaction (e.g.,
up to about 120.degree. C.). In some cases, the reaction may be
conducted at a temperature ranging from about 40.degree. C. to
about 80.degree. C. To avoid by-product formation, the reaction
mixture may be pressurized with CO while at a low temperature
(e.g., <0.degree. C.) and heating is introduced only after CO
has been allowed to contact the reaction mixture. If minimization
of by-product is desired, the CO pressure may be applied for a
period of time prior to heating the mixture (e.g., at least 5
minutes prior to heating).
[0129] In some embodiments, the ratio of catalyst to epoxide is
selected, based on other reaction conditions, so that the reaction
proceeds in an economical and time-feasible manner. In some
embodiments, the ratio of catalyst to epoxide is about 1:10000 on a
molar basis. In some embodiments, the molar ratio of catalyst to
epoxide is about 1:5000, is about 1:2500, is about 1:2000, is about
1:1500, is about 1:1000, is about 1:750, is about 1:500, is about
1:250, is about 1:200, is about 1:150, or is about 1:100. In some
embodiments, the concentration of the epoxide is in the range
between about 0.1 M and about 5.0 M. In some embodiments, the
concentration of the epoxide is in the range between about 0.5 M
and about 3.0 M.
[0130] In embodiments using a first catalyst to promote the first
carbonylation and a second catalyst different from the first
catalyst to promote the second carbonylation, the catalysts may be
present at a constant ratio and a constant concentration in the
reaction vessel or vessels or the concentrations or ratio of the
catalysts may be varied during the double carbonylation. The
reaction stream may include predominantly only the first catalyst
when it enters the reaction vessel, with the second catalyst being
introduced at a later point in the process. The first catalyst may
be predominantly separated from the intermediate lactone prior to
introduction of the second catalyst to the lactone, or,
alternatively, the second catalyst may be introduced to the
reaction stream without separation of the first catalyst from the
lactone. Alternatively, both the first catalyst and the second
catalyst may be present in the reaction stream throughout the
process.
[0131] In some embodiments, the catalyst is preferably present in
an amount sufficient to allow the reaction process to be completed
in a convenient time interval (e.g. less than about 24 hours, for
example less than about 3 hours). In real terms this can require
catalyst loadings ranging from about 0.0001 mole percent to about
20 mole percent based on the epoxide substrate. In certain
embodiments, the catalyst loading can range from about 0.0001 mole
percent to about 1 mole percent, e.g., from about 0.0001 mole
percent to about 0.1 mole percent or from about 0.0001 mole percent
to about 0.01 mole percent. In certain embodiments, the catalyst
loading can range from about 0.001 mole percent to about 20 mole
percent, e.g., from about 0.1 mole percent to about 1 mole percent
or from about 0.067 mole percent to about 5 mole percent. In some
embodiments, the catalyst loading is less than about 0.154 mole
percent based on the epoxide substrate. In one such embodiment, the
epoxide is ethylene oxide.
[0132] In some embodiments, the carbonylation reaction is
maintained for a period of time sufficient to allow complete, near
complete reaction of the epoxide to acid anhydride or as complete
as possible based on the reaction kinetics and or reaction
conditions. In some embodiments, the reaction time is maintained
for about 24 hours, about 12 hours, about 8 hours, about 6 hours,
about 3 hours, about 2 hours or about 1 hour. In some embodiments,
the reaction time is established as a residence time within the
reactor. The reaction can be halted by reducing the reactor
temperature or pressure, withdrawing a particular reactant or
introducing a quenching compound. The reaction may be halted at any
point or any percentage conversion of epoxide to acid
anhydride.
[0133] The catalyst or catalysts are preferably recycled from the
product stream and returned to the reaction stream after being
substantially separated from the acid anhydride product. In some
embodiments, the catalyst remains substantially dissolved in the
solvent throughout the separation and recycling. In some
embodiments, the reaction product is separated by crystallization
and filtration. In some embodiments, the catalyst recycling stream
is further processed after separation of the product. When two or
more catalysts are present, in some embodiments the catalyst
recycling stream is further processed to separate the different
catalysts into two or more catalyst recycling streams. The
separation of the different catalysts may only produce catalyst
recycling streams with different ratios of catalyst, or the
separation may substantially completely separate the different
catalysts. Further processing steps include, but are not limited
to, feeding the recycling stream to a flash drum to separate
volatiles, drying the recycling stream, heating or cooling the
recycling stream, removing spent catalyst, and adding solvent.
[0134] Separation
[0135] The separation may be accomplished by a variety of
separation means, including but not limited to solid-liquid,
gas-liquid, and liquid-liquid separation techniques. In some
embodiments, the portion of acid anhydride product stream separated
is between about 0% and about 100% of the reaction products. The
separation can result in a recycle stream comprising solvent and
catalyst and an acid anhydride stream. In some embodiments, the
separation results in all or nearly all of the reaction catalyst
being retained in the recycle stream.
[0136] In some embodiments, the temperature reduction of the second
reaction product stream 300 is decrease in temperature of between
1% and about 99% from the reaction temperature (on an absolute
scale). In some embodiments, the temperature of the second reaction
product stream 300 is decreased by between about 1.degree. C. and
about 600.degree. C. in the separation step 3. In some embodiments,
the pressure or the partial pressure of carbon monoxide of the
second reaction product stream 300 is lowered by between about 1
psig and about 5000 psig in the separation step 3.
[0137] In some embodiments the separation includes adding a
component to the reaction product stream. This component causes a
reduction in the solubility of the acid anhydride in the stream,
and results in precipitation of the acid anhydride. In some
embodiments, the reaction product stream is near or above the
saturation point of acid anhydride at particular reaction and
reactor exit conditions. In some embodiments, the separation method
is crystallization, filtration or sedimentation. Separation may be
accomplished with a variety of techniques including but not limited
to evaporative cooling crystallization, cooling crystallization,
flash drums, drying, filtering and combinations of these
techniques.
[0138] In some embodiments, the separation includes separating acid
anhydride in the vapor phase (e.g., distillation, flashing, etc.,).
In some embodiments, separation of the acid anhydride is
accomplished through liquid-liquid extraction. The extraction
process involves partitioning the reaction product stream into two
immiscible solvents. In the extraction, a portion of the acid
anhydride will be partitioned into one solvent and the other
solvent will contain at least the reaction catalyst. In some
embodiments, after the extraction, the solvent containing acid
anhydride product will be the acid anhydride product, and the
stream containing the catalyst will be recycled.
[0139] Carbonylation Reaction Products
[0140] In some embodiments, in the carbonylation reaction,
un-reacted epoxide may prevent the formation of an acid anhydride.
Without being bound by a particular theory, it is speculated that
the second carbonylation reaction, converting the beta-lactone to
acid anhydride does not proceed, unless all of the epoxide is
consumed.
[0141] As described above, the reaction product of the double
carbonylation reaction is an acid anhydride. In some embodiments,
the product is a cyclic anhydride. In some embodiments, the product
is succinic anhydride, methylsuccinic anhydride,
chloromethylsuccinic anhydride, ethylsuccinic anhydride, or
C.sub.5-30 acid anhydrides. Additionally, the reaction may produce
by-products, and the outlet of the reactor may contain un-reacted
reactants, as well as catalyst and solvent. In some embodiments,
the un-reacted reactants include beta-lactone, epoxide or carbon
monoxide. As such, the reaction may not proceed to completion and
may be considered a partial reaction.
EXAMPLES
[0142] The process parameters of the processes described in FIG. 1
may be modified to optimize the efficiency of the anhydride
production. The embodiment of FIG. 1 describes illustrative and
non-limiting process parameters suitable for one embodiment of the
present invention. In this figure, the solvent used is dioxane and
the selected parameters are based on the efficient conversion of
epoxide, separation of anhydride, and recycling of catalyst using
this solvent. The product stream is about 99.9 wt % succinic
anhydride. The gas stream exiting the second PSA unit is about 98.5
wt % CO, about 0.7 wt % methane, and about 0.5 wt % carbon dioxide.
The EO, dioxane, and dioxane-catalyst slurry are fed and combined
at a pressure of about 225 psia and a temperature of about 30 OC.
The CO is applied at a pressure of about 210 psia and a temperature
of about 100.degree. C. The reaction stream enters the reactor at a
pressure of about 215 psia and a temperature of about 50.degree.
C., and the product stream exits the reactor at a pressure of about
200 psia and a temperature of about 90.degree. C. The slurry exits
the evaporative cooling recrystallizer containing about 25 wt %
succinic anhydride at a pressure of about 160 psia and a
temperature of about 35.degree. C. The lights vented from the gas
stream of the recovery flash drum contain about 3 wt % dioxane,
about 21 wt % CO, about 34 wt % methane, and about 42 wt % carbon
dioxide.
[0143] Carbonylation catalysts and other related experimental
details are described in J. Am. Chem. Soc. 2007 (129) pp. 4948-4960
and the supporting information published therewith as well as U.S.
Pat. No. 6,852,865 and U.S. Patent Application Publication Nos.
2005/0014977 and 2007/0213524, the entirety of all of which are
hereby incorporated herein by reference.
[0144] It is to be understood that the embodiments of the invention
herein described are merely illustrative of the application of the
principles of the invention. Reference herein to details of the
illustrated embodiments is not intended to limit the scope of the
claims, which themselves recite those features regarded as
essential to the invention.
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