Synthesis and further reactivity studies of some transition metal gallyl complexes

Reactions of the anionic gallium(I) heterocycle salt, [K(tmeda)][Ga(DAB)] (DAB = {N(Dip)C(H)}2; Dip = C6H3Pri2-2,6), with a series of groups 6–9 and 11 metal halide complexes have given rise to the metal gallyl complexes, [CpCr(IMes){Ga(DAB)}] (IMes = :C{(Mes)NC(H)}2; Mes = mesityl), [M(tmeda){Ga(DAB)}2] (M = Mn, Fe or Co) and [Cu(dppe){Ga(DAB)}] (dppe = 1,2-bis(diphenylphosphino)ethane). The majority of the complexes have been crystallographically characterized. The reactivity of the previously reported copper(I) gallyl complex, [(IPr)Cu{Ga(DAB)}] (IPr = :C{(Dip)NC(H)}2), towards a variety of unsaturated substrates has been explored. Three crystallographically characterized complexes have arisen from this phase of the study, viz. [(IPr)CuCtriple bond; length of mdashCPh], [(IPr)Cu{Ga(DAB)}(Ctriple bond; length of mdashNBut)] and [(IPr)Cu{κ1-OC(O)C(double bond; length as m-dashCNHDip)(NHDip)}]. The results of these investigations show that the reactivity of [(IPr)Cu{Ga(DAB)}] is significantly different to that of related copper boryl complexes.