Synthesis of 2,3-Disubstituted Indoles by Radical Cyclization with Hypophosphorous Acid and Its Application to Total Synthesis of (±)-Catharanthine

Abstract

Radical cyclization of o-alkenylthioanilides using hypophosphorous acid and AIBN in the presence of Et 3 N proceeded smoothly to furnish the corresponding 2,3-disubstituted indoles in high yields.Utilizing the newly developed cyclization condition, a stereocontrolled total synthesis of (±)catharanthine has been completed.