New palladium(II)-N-heterocyclic carbene complexes containing benzimidazole-2-ylidene ligand derived from menthol: synthesis, characterization and catalytic activities

A new series of sterically hindered ligands containing (1R,2S,4R)-(+)-menthoxymethyl group attached to benzimidazole-based N-heterocyclic carbene (NHC), palladium-bis-NHC complexes and (kappa(2)-C,N)-palladacyclic NHC complexes have been synthesized and characterized using appropriate spectroscopic techniques. Catalytic performance of the palladium complexes has been investigated for allylic alkylation, Suzuki and Heck carbon-carbon coupling reactions. These complexes smoothly catalyse the carbon-carbon bond formation reactions. Copyright (C) 2016 John Wiley & Sons, Ltd.