Platinum-alkyl and hydride complexes supported by a tris(phosphino)borate ligand: structural and spectroscopic studies

摘要

The synthesis and characterization of platinum-methyl and hydride complexes containing the ligand [PhBP3] ([PhBP3]=[PhB(CH2PPh2)(3)](-)) are described. Metalation of [PhBP3][TBA] (1[TBA], [TBA]=[(Bu4N)-Bu-n](+)) with platinum methyl precursors provided the corresponding phosphine methyl platinum species [PhBP3]PtMe3(2) and [[kappa(2) -PhBP3]PtMe2][TBA] (3). The reactivity of octahedral 2 and square planar 3 are discussed, and their X-ray diffraction structures are reported. Octahedral Pt(IV) 2 was found to be very thermally and chemically robust. In contrast, the square planar Pt(II) complex 3 demonstrated reactivity at both the platinum center and the unbound phosphine. The reaction of 3 with one equivalent of elemental sulfur provided the corresponding phosphine-sulfide [[kappa(2) -PhB(CH2P(S)Ph-2)(CH2PPh2)(2)]PtMe2][TBA] (4). Similarly, the reaction of 3 with one equivalent of BH3.SMe2 generated the borane-protected complex [[kappa(2)-PhB(CH2P(BH3)Ph-2)(CH2PPh2)(2)]PtMe2][TBA] (5). Complex 5 was significantly less reactive than 3 to a variety of substrates under similar conditions; however, the reaction of 5 with additional BH3.SMe2 resulted in the formation of the platinum(I) bridged hydride species [[kappa(2)-PhB(CH2P(BH3)Ph-2)(CH2PPh2)(2)]Pt(mu-H)](2)[TBA](2) (6). (C) 2003 Elsevier Ltd. All rights reserved.