Gallane complexes with amido-amine ligands

Gallane complexes bearing amido-amine ligands -N(R)CH2CMe2CH2NMe2 [R = H or SiMe3 (TMS)], {H2Ga-[N(H) CH2CMe2CMe2CH2NM2]}(2), 1, H2Ga[N(TMS)CH2CMe2CH2 NMe2], 2, {H(Cl)Ga[N(H)CH2CMe2CH2NMe2]}(2), 3, {[(TMS)(2)N](H)Ga[N(H)CH2CMe 2CH2NMe2]}(2), 4, and HGa[N(TMS)CH2CMe2CH2NMe2](2), 5, were synthesized fro m the reactions of the quinuclidine adducts of mono- and dichlorogallane Wi th the corresponding lithium amides. Structural determinations of compounds 1, 3, and 4 showed all were dimeric with bridging amido groups. Rather tha n bond to gallium the tertiary amine groups in 1 and 4 were hydrogen-bonded to the amido N-H. In the structure of compound 3 the amine group occupied an axial position in the trigonal bipyramidal geometry of the five-coordina te gallium. The results were rationalized in terms of the steric and electr onic properties of gallium ligands.