Ortho-Metallated triphenylphosphine(2-diphenylphosphinophenyl) and related complexes of ruthenium(II): interaction of chlorohydridotris(triphenylphosphine)ruthenium(II) with methyl and trimethylsilylmethyl alkylating agents (Li, Mg, Zn); hydrido methyl and trimethylsilylmethyl complexes

Abstract

The interaction of chlorohydridotris(triphenylphosphine)ruthenium(II), RuHCl(PPh3)3, with lithium, magnesium, and zinc alkyls has been studied.With trimethylsilylmethyl-lithium and methyl-lithium in diethyl ether and tetrahydrofuran, unstable, very reactive hydridoalkyls, RuH(R)(PPh3)2(S)2(R = CH2SiMe3 or Me, and S = Et2O or C4H8O) are formed. When warmed these compounds readily lose Me4Si or CH4via an ortho-metallation reaction of PPh3 to give the hydrido-(η3-2-diphenylphosphinophenyl) species, RuH(C6H4PPh2)(PPh3)2(S). With an excess of methyl-lithium in diethyl ether and with magnesium and zinc dimethyls, lithium-, magnesium-, and zinc-containing methyl complexes are obtained. The reaction of RuHCl(PPh3)3 with lithium alkyls has been monitored by n.m.r. spectroscopy of the intermediates, and the isolated complexes have been characterised and their stereochemistries derived from i.r. and 1H and 31P n.m.r. spectroscopy.The isolated and chemicallyanalysed new complexes are: RuHMe(PPh3)2(Et2O)2, RuHMe(PPh3)2(MeLiOEt2)2, RuMe(C6H4PPh2)(PPh3)2(Et2O), RuMe(C6H4PPh2)(PPh3)(MeLiOEt2)2, RuH(C6H4PPh2)(PPh3)2(Et2O), RuMe(C6H4PPh2)(PPh3)2(thf), {RuH(C6H4PPh2)(PPh3)2}2(Zn2Me3Cl), {RuH(C6H4PPh2)(PPh3)2}2[Mg2Me3Cl(Et2O)2].