Engineering Polymer-Enhanced Bimetallic Cooperative Interactions in the Hydrolytic Kinetic Resolution of Epoxides

Authors

  • Xiaolai Zheng,

    1. School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
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  • Christopher W. Jones,

    1. School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
    2. School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA 30332, USA
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  • Marcus Weck

    1. School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
    2. Molecular Design Institute and Department of Chemistry, New York University, New York, NY 10003, USA, Fax: (+1)-212-995-4895
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Abstract

Through systematic variations of the length of oligo(ethylene glycol)-based linkers and the catalyst density of poly(styrene)-supported cobalt-salen catalysts, we have elucidated an optimal catalyst flexibility and density of polymeric Co-salen catalysts for the hydrolytic kinetic resolution (HKR) of racemic terminal epoxides that follows a bimetallic cooperative pathway. The optimized polymeric catalyst brings the two cooperative Co-salen units to a favorable proximity efficiently and hence displays significantly improved catalytic performance in the HKR compared with its monomeric small molecule analogue. Complex Co(5b), representing the most active poly(styrene)-supported HKR catalyst known so far, can effect the resolution of a variety of epoxides to reach ≥98 % ee in 6–24 h with a low cobalt loading of 0.01–0.1 mol %.

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