Synthesis and spectroscopic characteristics of bis(ethenyldimethylsilylmethyl)platinum(II) complexes containing tertiary phosphine ligands

Various complexes L 2 Pt(CH 2 SiMe 2 CH : CH 2 ) 2 have been synthesized by diene displacement from (cod)Pt(CH 2 SiMe 2 CH : CH 2 ) 2 [L= PMe 3 , PEt 3 , PMePh 2 , PPh 3 ; L 2 = dppm, dppe, dppp, dppb, dppf]. With monodentate phosphines, monophosphine complexes LtsqbPt(CH 2 SiMe 2 CH : CH 2 )(CH 2 SiMe 2 CH : CH 2 ) may be formed, in which tetracoordination of platinum is completed by η 2 -binding of one ethenylsilyl ligand. With tricyclohexylphosphine, this is isolated as the sole product, while with less bulky phosphines inseparable mixtures develop of monophosphine, bis-phosphine and diene complexes. All of these species have been characterized by 1 H, 13 C and 31 P NMR and IR techniques.