Exploration of Cocatalyst Effects on a Bimetallic Cobalt Catalyst System: Enhanced Activity and Enantioselectivity in Epoxide Polymerization

Widger, Peter C. B.; Ahmed, Syud M.; Coates, Geoffrey W.

Exploration of Cocatalyst Effects on a Bimetallic Cobalt Catalyst System: Enhanced Activity and Enantioselectivity in Epoxide Polymerization

Type

Article

Authors

Widger, Peter C. B.
Ahmed, Syud M.
Coates, Geoffrey W.

KAUST Grant Number

KUSC1-018-02

Date

2011-07-26

Abstract

Organic ionic compounds were synthesized and investigated as cocatalysts with a bimetallic cobalt complex for enantioselective epoxide polymerization. The identities of both the cation and the anion were systematically varied, and the subsequent reactivity was studied. The nature of the ionic cocatalyst dramatically impacted the rate and enantioselectivity of the catalyst system. The ionic cocatalyst [P(N=P(N(CH2)4)3) 4 +][tBuCO2 -] in combination with a bimetallic cobalt complex produced a catalyst system that exhibited the greatest activity and selectivity for a variety of monosubstituted epoxides. © 2011 American Chemical Society.

Citation

Widger PCB, Ahmed SM, Coates GW (2011) Exploration of Cocatalyst Effects on a Bimetallic Cobalt Catalyst System: Enhanced Activity and Enantioselectivity in Epoxide Polymerization. Macromolecules 44: 5666–5670. Available: http://dx.doi.org/10.1021/ma201078m.

Acknowledgements

We thank the NSF (CHE-0809778) and the King Abdullah University of Science and Technology (KAUST; Award KUSC1-018-02) for support of this research. The authors are grateful to Dr. Kevin J. T. Noonan for helpful suggestions and Dr. Heloise Therien-Aubin for GPC analysis of isotactic poly(1,1,1-trifluoro-2,3-epoxypropane).