LAUSR

Abstract Stereoselective synthesis of natural and unnatural compounds containing the pyrrolizidine skeleton is of immense interest to synthetic organic chemists due to their enormous biological importance. In addition to the numerous total synthetic approaches, the development of direct synthetic strategies for the enantioselective preparation of pyrrolizidines has shown rapid progress in the last decade. The 1,3-dipolar cycloaddition reaction of a dipole and a dipolarophile has been found to be the most useful tool for the direct asymmetric synthesis of pyrrolizidines, and Michael addition followed by cyclisation is implicated for the preparation of pyrrolizidinones. In this digest review, we discuss the direct approaches for the preparation of optically active pyrrolizidines and pyrrolizidinones.