Bimetallic catalytic complexes for the copolymerization of carbon dioxide and an epoxide
The present invention provides a novel catalyst of formula (I): wherein M is selected from Zn(H), Co(II), Mn(II), Mg(II), Fe(II), Cr(III)-X or Fe(III)-X, and the use thereof in polymerizing carbon dioxide and an epoxide.
1. A catalyst of formula (1)
wherein R 1 and R 2 are independently hydrogen, alkyl, haloalkyl, aryl, halide, amine, a nitro group, an ether group, a silyl ether group, a nitrile group or an acetylide group;
R 3 is substituted C 3 alkylene;
R 4 is H, alkyl, aryl or alkylaryl;
E 1 is C, E 2 is O, S or NH or E 1 is N and E 2 is O;
X is OCOCH 3 , OCOCF 3 , OSO 2 C 7 H 7 , OSO(CH 3 ) 2 , alkyl, alkoxy, halide or amido; and
M is Zn(II), Co(II), Mg (II), Co (III)-X, or Fe(III)—X.
2. A catalyst as claimed in claim 1 wherein R 1 and R 2 are independently selected from hydrogen, tBu, Me, CF 3 , phenyl, F, Cl, Br, I, NMe 2 , NEt 2 , NO 2 , OMe, OSiEt 3 , CNMe, CN and c≡C-Ph.
3. A catalyst as claimed in claim 1 wherein R 3 is 2,2-dimethylpropylene, sec-butylene, 1,1-dimethylpropylene, 1,2-dimethylpropvlene, 1-ethylpropylene, 1-ethyl-2-methylpropylene, or 1,1,2-trimethylpropylene.
4. A catalyst as claimed in claim 1 wherein R 4 is H, Me, Et, Bn, tBu or Ph.
5. A catalyst as claimed in claim 1 wherein X is OCOCH 3 , OCOCF 3 , OSO 2 C 7 H 7 , OSO(CH 3 ) 2 , Et, Me, PhOEt, OMe, OiPr, OtBu, Cl, Br, 1, F, N(iPr) 7 or N(SiMe 3 ) 2 .
6. A catalyst having a structure selected from: