Asymmetric Hydroxylation of 1-Chloro-2-butene with Ascorbic Acid and Optically Active Polymer-Supported Copper (I) Ion Catalytic System

Heterogeneous asymmetric hydroxylation of 1-chloro-2-butene to give optically active 1-buten-3-ol was carried out with ascorbic acid and optically active polymers such as poly (l-menthyl methacrylate) (PMnMA) and poly ((-) -bornyl methacrylate) (PBoMA) which supported copper (I) in aqueous acetone at pH4.0 under an argon atmosphere at 30°C. The results were discussed as compared with homogeneous systems using ascorbic acid and optically active compounds such as l-menthyl acetate, (-) -bornyl acetate, (+) -dimethyl tartrate, and saccharose under similar reaction conditions. The polymeric catlyst systems showed high asymmetric induction compared with that in the absence of the polymeric supports. The observations suggest that the reaction proceeds through the π-allyl copper chloride intermediate in which interaction between the reaction substrate and optically active ligand is stabilized by the hydrophobic micro-atmosphere on the surface of the polymeric support.