Pd(II) complexes with mixed benzothiazolin-2-ylidene and phosphine ligands and their catalyic activities toward C-C coupling reactions

Novel Pd(II) mixed N,S-heterocyclic carbene (NSHC)-phosphine complexes of the general formula [PdBr2(NSHC)(PR3)] were obtained from bridge cleavage of dinuclear NSHC complexes of type [PdBr2(NSHC)](2) [NSHC = 3-benzylbenzothiazolin-2-ylidene and 3-propylbenzothiazolin-2-ylidene] with triphenylphosphine, tricyclohexylphosphine and 2-diphenylphosphanyl-pyridine. All complexes have been fully characterized by H-1 and C-13 NMR spectroscopy, ESI mass spectrometry and elemental analysis. The X-ray crystal structures of complexes 3-8 are reported. The complexes exhibit moderate to good catalytic activity in the Suzuki-Miyaura coupling reaction of aryl bromides and chlorides.