Abstract

A novel approach to the asymmetric reduction of dihydro-ß-carboline derivatives to the corresponding tetrahydro-ß-carbolines is described based on the supramolecular lyophilized complex formed from ß-cyclodextrin/ imines as an enzyme mimetic and palladium hydride as the reducing agent. The methodology allowed us to develop a short and efficient preparation of (R)-harmicine and (R)-deplancheine alkaloids in high overall yields and ee of 89 and 90%, respectively. © 2009 American Chemical Society.