Radical Cyclization of Trichloroacetamides: Synthesis of Lactams

Abstract

Trichloroacetamides can act as radical precursors to synthesize nitrogen-containing heterocycles in a variety of processes, mainly involving atom transfer radical cyclizations (ATRC), mediated by Cu(I) or Ru(II) catalysts, and the hydride reductive method, employing either Bu3SnH or (Me3Si)3SiH, or recently NaBH3CN. Additionally, amine-mediated single-electron transfer cyclizations, as well as radical processes promoted by Ni, Fe, Mn, Ti, and Ag, have been developed.