Efficient and practical polymeric catalysts for heterogeneous asymmetric dihydroxylation of olefins

Abstract

High enantioselectivity (>99% ee) and reactivity in heterogeneous catalytic asymmetric dihydroxylation (AD) of olefins have been achieved using new polymeric cinchona alkaloids containing 1,4-bis(9-O-quininyl)phthalazine ((QN)(2)-PHAL), which can be synthesized more economically than their homogeneous analogue, 1,4-bis(9-O-dihydroquininyl)phthalazine ((DHQ)(2)-PHAL). (C) 1996 Elsevier Science Ltd