Phosphine-based redox catalysis in the direct traceless staudinger ligation of carboxylic acids and azides

Abstract

Redox catalysis: Aryl amides, imides, lactams, and dipeptides are obtained through a direct Staudinger ligation mediated by phosphine-based redox catalysis (see scheme). Mechanistic studies indicate the involvement of a phosphonium carboxylate intermediate that leads to a 1,3-acyl migration and thus results in C-N bond formation. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.