SYNTHESIS AND CRYSTAL-STRUCTURE OF THE AMIDO PALLADATE (PPH4)2[PD2CL4(NH2)2].CH2CL2 AND OF THE BENZAMIDINE PALLADATE PPH4([PH-C(NH2)(NH)]PDCL3).CH3CN

Orange crystals of (PPh4)2[Pd2Cl4(NH2)2] have been prepared by the reaction of (PPh4)2[Pd2Cl6] with N,N,N'-tris(trimethylsilyl)benzamidine in boiling acetonitrile in the presence of water, and orange brown crystals of PPh4{[Ph-C(NH2)(NH)]PdCl3} by the reaction of the amidinato complex PPh4[Ph-C(NSiMe3)2PdCl2] with HCl gas in acetonitrile solution. The complexes were characterized by IR spectroscopy as well as by X-ray structure determinations. (PPh4)2[Pd2Cl4(NH2)2].CH2Cl2: Space group P 1BAR, Z = 1, 2784 observed unique reflections, R = 0.043. Lattice dimensions at -60-degrees-C: a = 1053.3(4), b = 1081.1(4), c = 1249.2(4) pm, alpha = 102.90(2)-degrees, beta = 110.44(2)-degrees, gamma = 102.23(2)-degrees. The compound consists of PPh4+ ions and centrosymmetric anions [Pd2Cl4(NH2)2]2- with bridging chlorine atoms and terminal amido groups. PPh4{[Ph-C(NH2)(NH)]PdCl3}.CH3CN: Space group C2/c, Z = 8, 1183 observed unique reflections, R = 0.033. Lattice dimensions at -60-degrees-C: a = 3106.7(6), b = 1059.0(1), c = 1818.0(4) pm, beta = 90.98(2)-degrees. The compound consists of PPh4+ ions, [Ph-C(NH2)(NH)PdCl3]- ions, and included CH3CN molecules. In the anion the benzamidine ligand is bound via the nitrogen atom of the imido group.