Silicone??Supported Cinchona Alkaloid Derivatives as Insoluble Organocatalysts in the Enantioselective Dimerization of Ketenes

D Cancogni, A Mandoli, RP Jumde…

Index: Cancogni, Damiano; Mandoli, Alessandro; Jumde, Ravindra P.; Pini, Dario European Journal of Organic Chemistry, 2012 , # 7 p. 1336 - 1345

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Citation Number: 5

Abstract

Abstract A straightforward procedure is presented for the covalentimmobilization of ester and silyl ether derivatives of theCinchona alkaloid 10, 11-dihydroquinidine within insoluble cross- linked silicone elastomeric films. These materials were effective heterogeneous organocatalysts in the asymmetric dimerization of ketenes, which provided chiral Weinreb β- ketoamides in 28–83% yield and 79–99% ee in the course of several recycles. A ...