Methanolysis with a Polymer-Supported Organocatalyst
S. H. Youk, S. H. Oh, H. S. Rho, J. E. Lee, J. W. Lee, C. E. Song*
Sungkyunkwan University, Suwon and AmorePacific Corporation, Yongin, Korea
22. Juni 2009 (online)
A polymer-supported cinchona-based sulfonamide 1 was prepared by treatment of 9-amino-(9-deoxy)-epiquinine with 4-vinylbenzylsulfonyl chloride followed by the copolymerization with styrene and 1,4-divinylbenzene (eq. 1). The sulfonamide 1 catalyzed the ring-opening methanolysis of cyclic anhydrides in MTBE to afford the corresponding hemiesters in up to >99% yield with up to 97% ee (7 examples, eq. 2).