Process for producing polycarbonates and a coordination complex used therefor

1. A process for producing a polycarbonate comprising subjecting an epoxide and carbon dioxide to a copolymerization reaction in the presence of a complex,

wherein the complex is represented by formula (4a)

wherein:

M is Co or Cr;

X′ is each independently halogen; C 6 -C 20 aryloxy unsubstituted or substituted by nitro; or C 1 -C 20 carboxy unsubstituted or substituted by halogen;

A is oxygen;

Q is trans-1,2-cyclohexylene, ethylene or substituted ethylene;

R 1 , R 2 , R 4 , R 6 , R 7 and R 9 are hydrogen;

R 5 and R 10 are each independently hydrogen, tert-butyl, methyl or isopropyl;

one or both of R 3 and R 8 are —[YR 41 3-m {(CR 42 R 43 ) n NR 44 R 45 R 46 } m ]X′ m or —[PR 51 R 52 ═N═PR 53 R 54 R 55 ]X′, the other being hydrogen, methyl, isopropyl or tert-butyl;

Y is C or Si;

R 41 , R 42 , R 43 , R 44 , R 45 , R 46 , R 51 , R 52 , R 53 , R 54 and R 55 are each independently hydrogen; C 1 -C 20 alkyl; C 1 -C 20 alkyl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 2 -C 20 alkenyl; C 2 -C 20 alkenyl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 7 -C 20 alkylaryl; C 7 -C 20 alkylaryl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 7 -C 20 arylalkyl; C 7 -C 20 arylalkyl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; or a metalloid radical of group XIV metal substituted by hydrocarbyl, two of R 44 , R 45 and R 46 , or two of R 51 , R 52 , R 53 , R 54 and R 55 being optionally fused together to form a bridged structure;

m is an integer in the range of 1 to 3; and

n is an integer in the range of 1 to 20.

2. The process of claim 1 , wherein the epoxides are selected from the group consisting of C 2 -C 20 alkylene oxide unsubstituted or substituted by halogen or alkoxy, C 4 -C 20 cycloalkene oxide unsubstituted or substituted by halogen or alkoxy, and C 8 -C 20 styrene oxide unsubstituted or substituted by halogen, alkoxy or alkyl.

3. The process of claim 1 , wherein the complex is represented by any one of formulae (5a) to (5e):

wherein

M is Co or Cr;

R 61 , R 62 and R 63 are each independently hydrogen, methyl, isopropyl or tert-butyl;

X is halogen; C 6 -C 20 aryloxy; C 6 -C 20 aryloxy having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 1 -C 20 carboxy; C 1 -C 20 carboxy having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 1 -C 20 alkoxy; C 1 -C 20 alkoxy having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 1 -C 20 alkylsulfonato; C 1 -C 20 alkylsulfonato having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 1 -C 20 amido ; or C 1 -C 20 amido having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; and

n is an integer in the range of 1 to 20.

4. The process of claim 3 , wherein the complex is a compound of any one of formulae (6a) to (6f):

wherein X is 2,4-dinitrophenoxy;

wherein X is 2,4-dinitrophenoxy;

wherein X is Cl;

wherein X is 2,4-dinitrophenoxy, and R is methyl, isopropyl or tent-butyl;

wherein X is 2,4-dinitrophenoxy, and R is methyl, isopropyl or tert-butyl;

wherein X is Cl.

5. A process for producing a polycarbonate comprising the steps of:

subjecting an epoxide and carbon dioxide to a copolymerization reaction in the presence of a complex;

treating the reaction mixture containing the polycarbonate and the complex with a composite-forming material to form a composite of the complex and the composite-forming material; wherein the composite-forming material is an inorganic solid, a polymer, or a mixture thereof;

removing the composite from the reaction mixture; and

recovering the complex from the composite by treating the composite in a medium which does not dissolve the composite-forming material with an acid and/or a non-reactive metal salt, and isolating the complex released into the medium:

wherein the epoxide is selected from the group consisting of C 2 -C 20 alkylene oxide unsubstituted or substituted by halogen or alkoxy, C 4 -C 20 cycloalkene oxide unsubstituted or substituted by halogen or alkoxy, and C 8 -C 20 styrene oxide unsubstituted or substituted by halogen, alkoxy or alkyl; and the complex is represented by formula (4a); the inorganic solid is silica, and the polymer has carboxylic acid group; and the non-reactive metal salt is M′BF 4 , wherein M′ is Li, Na or K:

M is Co or Cr;

X′ is each independently halogen; C 6 -C 20 aryloxy unsubstituted or substituted by nitro; or C 1 -C 20 carboxy unsubstituted or substituted by halogen;

A is oxygen;

Q is trans-1,2-cyclohexylene, ethylene or substituted ethylene;

R 1 , R 2 , R 4 , R 6 , R 7 and R 9 are hydrogen;

R 5 and R 10 are each independently hydrogen, tert-butyl, methyl or isopropyl;

one or both of R 3 and R 8 are —[YR 41 3-m {(CR 42 R 43 ) n NR 44 R 45 R 46 } m ]X′ m or —[PR 51 R 52 ═N═PR 53 R 54 R 55 ]X′, the other being hydrogen, methyl, isopropyl or tert-butyl;

Y is C or Si;

R 41 , R 42 , R 43 , R 44 , R 45 , R 46 , R 51 , R 52 , R 53 , R 54 and R 55 are each independently hydrogen; C 1 -C 20 alkyl; C 1 -C 20 alkyl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 2 -C 20 alkenyl; C 2 -C 20 alkenyl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 7 -C 20 alkylaryl; C 7 -C 20 alkylaryl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; C 7 -C 20 arylalkyl; C 7 -C 20 arylalkyl having one or more functional moieties selected from the group consisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorous; or a metalloid radical of group XIV metal substituted by hydrocarbyl, two of R 44 , R 45 and R 46 , or two of R 51 , R 52 , R 53 , R 54 and R 55 being optionally fused together to form a bridged structure;

m is an integer in the range of 1 to 3; and

n is an integer in the range of 1 to 20.

6. The process of claim 5 , wherein the step of treating the reaction mixture with the composite-forming material is conducted by adding the composite-forming material to the reaction mixture and the composite is separated from the reaction mixture by filtration; or by passing the reaction mixture through a column filled with the composite-forming material.

7. The process of claim 5 , wherein the complex is represented by formula (5e); the composite forming material is silica or cross-linked poly(acrylic acid); the acid is 2,4-dinitrophenol; and the non-reactive metal salt is NaBF 4 ;

wherein

M is Co;

R 61 and R 62 are methyl;

X is 2,4-dinitrophenoxy; and

n is 3.