A new heteroleptic gallium(III) complex, Ga(6)Cl(6)(mdea)(6) (1 x 2 CHCl(3)) (mdeaH(2) = N-methyl diethanolamine) was prepared in good yield by a chloro-aminoalkoxo exchange reaction and used as a synthon for the synthesis of a novel group 13 heterometallic derivative, Ga(2)Al(4)(O)(2)(mdea)(2)(OPr(i))(10) (2 x 2 CHCl(3)), the latter acting as a facile single source precursor for the sol-gel preparation of the mixed Al-Ga oxide as a high surface area support for gold catalysts.