Synthesis and structural characterization of Pd(II) and Cu(I) complexes containing dithiophosphorus ligand and their catalytic activities for Heck reaction

2,4-Bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (Lawesson's reagent) was made to react with benzylamine to produce [(PhCH2NH)(p-C6H4OMe)PS2](-) [PhCH2NH3](+) in a very facile manner. From the abovementioned product, two new complexes {Pd[(PhCH2NH)(p-C6H4OMe)PS2](2)} (C1) and (Cu-2(PPh3)(2)[(PhCH2NH)(p-C6H4OMe)PS2](2)} (C2) were obtained in high yields whose molecular structures were ascertained by X-ray diffraction analysis, IR and NMR spectroscopy, and elemental analysis. The catalytic properties of both complexes were evaluated in the Heck reaction. High turnover numbers (TONs) and yields were observed for palladium catalyst and it was revealed that dicopper(I) complex by a distance of 2.84 angstrom between metal ions, bearing triphenylphosphine and dithiophosphorus ligands, can catalyze the Heck reaction. This is the first report of Cu(I) complex as catalyst in the Heck reaction. Natural bonding orbital (NBO) analysis for Cl indicated that natural charge on Pd atom is -0.07e and Pd atom has formed four sigma bonds with S atoms. Similarly, NBO analysis revealed no significant Cu center dot center dot center dot Cu interaction in dicopper complex C2. (C) 2016 Elsevier Ltd. All rights reserved.