Synthesis, structure, and characterization of picolyl‐ and benzyl‐linked biphenyl palladium N‐heterocyclic carbene complexes and their catalytic activity in acylative cross‐coupling reactions
Nalluchamy Muniyappan, Shahulhameed Sabiah
Abstract
Abstract N‐heterocyclic carbene ligands with picolyl (L 1 H 2 Br 2 , L 3 H 2 Br 2 ) and benzyl (L 2 H 2 Br 2 , L 4 H 2 Br 2 ) linked biphenyl backbone were synthesized and characterized. Their palladium(II) complexes [PdL 1 ]Br 2 ( 1 ), [PdL 2 Br 2 ] ( 2 ), [PdL 3 ]Br 2 ( 3 ), and [PdL 4 Br 2 ] ( 4 ) were synthesized by direct method using Pd(OAc) 2 . All complexes ( 1 – 4 ) were characterized by CHN analysis, electrospray ionization‐MS, nuclear magnetic resonance, and single‐crystal X‐ray diffraction. Molecular structures confirm the distorted square planar geometry around the Pd(II) center. All of them showed good catalytic activity in acylative Suzuki cross coupling of phenyl boronic acid with benzoyl chloride to afford benzophenone in good yields.