N-Arylation of Sterically Hindered NH-Nucleophiles: Copper-Mediated Syntheses of Diverse N-Arylindole-2-carboxylates

Abstract

Indole-carboxylates are N-arylated with 2-bromopyridines using stoichiometric copper(II) oxide/potassium carbonate to give various N-(2-pyridyl)-substituted indole-2-carboxylates and with bromobenzenes using stoichiometric copper(I) iodide/N,N'-dimethylethylenediamine to give various N-#substituted phenyl#-substituted indole-2-carboxylates. These results expand the scope of metal-catalyzed N-arylation using heterocyclic amines with steric bulk and weak nucleophilicity.