Iridium and Ruthenium Complexes with Chelating N-Heterocyclic Carbenes: Efficient Catalysts for Transfer Hydrogenation, β-Alkylation of Alcohols, and N-Alkylation of Amines

Abstract

Air-stable Ir and Ru complexes of a chelating pyrimidine-functionalized N-heterocyclic carbene were synthesized. The complexes were characterized by NMR spectroscopy and single-crystal X-ray diffraction and were found to be catalytically active for transfer hydrogenation, β-alkylation of secondary alcohols with primary alcohols, and N-alkylation of amines with primary alcohols. Notably, the Ir complexes were found to catalyze the N-alkylation of amines using the mild base NaHCO3.