Syntheses and characterization of the palladium(II) and copper(II) complexes of the new 1,1-dithiolate ligand, 1,3-dithiepin-2-carbodithiolate
摘要:
The synthesis of a new 1,1-dithiolate ligand, 1,3-dithiepin-2-carbodithiolate (L2-), has been accomplished from the reaction of carbon disulfide with the lithium salt of 1,3-dithiepin. Copper(II) and palladium(II) complexes of the formula ML2(2-) were isolated as the tetraethylammonium salts. Proton nuclear magnetic resonance spectra of the free ligand and the palladium salt suggest a good deal of 'Huckel' aromatic character in the seven membered dithiepin ring. Electron spin resonance spin Hamiltonian parameters obtained from frozen glass samples of the copper(II) complex suggest a highly delocalized four membered chelate ring. Taken together, these data suggest the dithiepin ring is a strong pi-acceptor in these complexes.