Abstract
This paper describes the asymmetric tandem conjugate addition-protonation reaction of various α-cyano ketones, α-cyano esters and β-keto esters with 2-chloroacrylnitril using 6′-hydroxy cinchona alkaloids as dual function catalysts. The desired products, which contain 1,3-tertiary-quaternary stereocenters, were obtained in moderate to good diastereoselectivities and excellent enantioselectivities (12 cyclic and acyclic examples, up to 25:1 dr, up to 99% ee).