Reductive elimination of [AlH2]+ from a cationic Ga-Al dihydride.

Oxidative addition of TMEDA-supported [AlH2]+ to [{BDI}Ga] (BDI = {HC(C(CH3)N(2,6-iPr2-C6H3))2}) provides [{BDI}Ga(H)-Al(H)(tmeda)][B(C6H3-3,5-Me2)4] (TMEDA = N,N,N'N'-tetramethylethylenediamine) with a covalent metal-metal bond. The reaction is readily reversed by substituting TMEDA for an N-heterocyclic carbene or dissolving in THF.