A formal catalytic asymmetric synthesis of (+)-biotin with modified cinchona alkaloids

A formal catalytic asymmetric synthesis of (+)-biotin was realized. The key steps involve a catalytic, highly enantioselective and quantitative desymm etrization of a meso cyclic anhydride followed by a one-pot chemoselective reduction to form the optically active lactone intermediate in the Goldberg -Sternbach (+)-biotin synthesis.