Synthesis and characterization of three group 10 complexes containing nido-carborane diphosphine: [MCl(PPh 3){7,8-(PPh 2) 2-7,8-C 2B 9H 10}] (M = Ni, Pd, Pt)

Abstract

Three group 10 complexes containing nido-carborane diphosphine, [NiCl(PPh 3){7,8-(PPh 2) 2-7,8-C 2B 9H 10}] ( 1), [PdCl(PPh 3){7,8-(PPh 2) 2-7,8-C 2B 9H 10}] · 1.25CH 2Cl 2 ( 2) and [PtCl(PPh 3){7,8-(PPh 2) 2-7,8-C 2B 9H 10}] · 2.5CH 2Cl 2 ( 3) have been synthesized by the reactions of [M(PPh 3) 2Cl 2] (M = Ni, Pd, Pt) with closo carborane diphosphine 1,2-(PPh 2) 2-1,2-C 2B 10H 10 in ethanol. For complex 3, it could also be obtained under solvothermal condition. All three complexes were characterized by elemental analysis, FT-IR, 1H and 13C NMR spectroscopy and X-ray structure determination. Single crystal structures show that their structures are similar to each other. In each complex, the nido [7,8-(PPh 2) 2-7,8-C 2B 9H 10] −, which resulted from the degradation of the initial closo ligand 1,2-(PPh 2) 2-1,2-C 2B 10H 10 during the reaction process, was coordinated bidentately through the P atoms to M(II) ion, and this resulted in a stable five-membered chelating ring between the bis-diphosphine ligand and the metal. The coordination mode of the metal can be described as a slightly distorted square-planar, in which the remaining two positions were occupied by one Cl − and one PPh 3 group.