A recyclable non-immobilized siloxy serine organocatalyst for the asymmetric direct aldol reaction

摘要

A recyclable siloxy-L-serine organocatalyst has been developed to catalyze asymmetric direct aldol reactions in[bmim][BF4],furnishing the p-hydroxy carbonyl scaffold in high enantio-and diastereoselectiv-ities using a selection of aromatic aldehydes and cycloalkanes.The siloxy serine organocatalyst in the ionic liquid can be reused for up to four successive cycles with comparable enantioselectivities.