Decomposition of monochlorogallane, [H2GaCl]n, and adducts with amine and phosphine bases: Formation of cationic gallane derivatives

Article abstract of DOI:10.1021/ic050986j

Thermal decomposition of monochlorogallane, [H₂GaCl] _n, at ambient temperatures results in the formation of subvalent gallium species. To Ga[HGaCl₃], previously reported, has now been added a second mixed-valence solid, Ga₄-[HGaCl₃] ₂[Ga₂Cl₆] (1), the crystal structure of which at 150 K shows a number of unusual features. Adducts of monochlorogallane, most readily prepared from the hydrochloride of the base and LiGaH₄ in appropriate proportions, include not only the 1:1 molecular complex Me ₃P·GaH₂Cl (2), but also 2:1 amine complexes which prove to be cationic gallane derivatives, [H₂Ga(NH₂R) ₂]⁺Cl^-, where R = ^tBu (3a) or ^sBu (3b). All three of these complexes have been characterized crystallographically at 150 K.