Structural characterization and a new one-pot synthesis of trans-chloro(phenyl)bis(triphenylphosphane)nickel(II)

trans-[NiCl(Ph)(PPh3)(2)], the organometallic precursor for a new class of neutral polymerization catalysts, has been synthesized via a new synthetic route. The previously used alkylaluminum compounds are replaced by zinc dust for the reduction of the nickel(II) salt in the presence of triphenylphosphane forming the intermediate Ni(PPh3)(4). In a one-pot reaction, chlorobenzene then adds oxidatively to the intermediate to form the title compound, which was structurally characterized, in high yields. Its geometry is compared to known structures of the higher homologues; of group 10. All complexes adopt a distorted square-planar geometry, but the parent structure shows significantly shorter metal-ligand bond lengths than its Pd and Pt congeners, as expected, Density functional theory calculations (B3LYP/6-31G*) on the full structure are in very good agreement with the solid-state structure. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003).