A rare P, C-bridged bimetallic palladium complex

Reaction of (cod) PdCl2 with two molar equivalents of trimethylphosphine (P(CH3)(3)) followed by equivalent mole of [Li2L], [L = C(Ph2P = NSi(CH3)(3))(2)](2-)(1) in THF at ambient temperature, did not yield the anticipated methanediide-Pd complex. However, a C-H activation of one methyl group of one P(CH3)(3) ligand on each of two Pd atoms occurred to form, ultimately, a rare example of an unusual P, C-bridged bimetallic palladium complex [{(H3C)(3)P) PdCl}(2)(mu: k(1), k(1) - ((H3C)(2)PCH2)(2)] (2). The cod was displaced initially and the completely protonated form of the ligand, H2L, and LiCl salt were all generated byproducts of the reaction with the methanediide. The dipalladium complex (2) was fully characterized including solution NMR spectra and a solid state X-ray crystal structure determination. The character of forming metal-ligand bonds in the complex was evaluated with Gaussian03 DFT calculations and the NBO analysis is also presented. Application of NMR Spin-Work simulation and DFT calculation data, the complicated P-31 NMR spectrum pattern and P-P spin coupling constants are fully obtained and assigned. (C) 2018 Elsevier B.V. All rights reserved.