Stereoselective 5-exo-trig radical cyclization in the enantioselective synthesis of Pregabalin

摘要

A practical stereoselective 5-exo-trig radical cyclization procedure was developed in order to prepare enantiomerically pure GABA derivative precursors (4-alkyl-pyrrolidin-2-ones).This procedure allows much more rapid access to optically pure GABA derivatives,such as the powerful antiepileptic agent (S)-(+)-3-aminomethyl-5-methylhexanoic acid (Pregabaline).