Synthesis, molecular and electronic structure of the first homoleptic complex of platinum with a secondary phosphine

Abstract

The reaction of CpPt(η 3-C 3H 5) with PBu 1 2H in acetone gives the Pt(0) mononuclear derivative Pt(PBu 1 2H) 3 ( 1). As demonstrated by variable temperature 31P 1H NMR spectra, complex 1 dissociates one of the phosphines in toluene solution affording the 14e − Pt(PBuP 1 2H) 2. The crystal and molecular structure of 1 was solved by X-ray diffraction which reveals a trigonal planar disposition of the phosphine molecules (C 24H 57P 3Pt: hexagonal, space group P6 3/m, a = b = 10.4150(11), c = 16.263(3) A ̊ , Z = 2 ). The PH hydrogen atoms were located in the Fourier map and were found to lie in the coordination plane, with the t-butyl substituents in an eclipsed configuration. Ab initio and molecular dynamics calculations essentially confirm the structure obtained by X-ray diffraction. An agostic PtHP interaction was excluded and the geometry was explained in terms of steric interactions.