Palladium(II)-NHC complexes containing benzimidazole ligand as a catalyst for C-N bond formation

The reaction of 2-(2-bromoethyl)-1,3-dioxane with 1-alkylbenzimidazole derivatives results in the formation of the new benzimidazoliumsalts (1). The reaction of Pd(OAc)(2) with1,3-dialkylbenzimidazoliumsalts(1a-c) yields palladium N-heterocyclic carbene (NHC) complexes (2a-c). All synthesized compounds were characterized by (HNMR)-H-1, (CNMR)-C-13, IR and elemental analysis techniques which support the proposed structures. As catalysts, these new palladium complexes offer a simple and efficient methodology for the synthesis of triarylamines and secondary amines from anilines and amines and in a single step with potassium tertiary butoxide as a base. Copyright (C) 2010 John Wiley & Sons, Ltd.