The N-methyl-2-(methylamino)troponimine [(Me)(2)ATI]H reacts with bis[bis(trimethylsilyl)amido]tin(II) to yield [(Me)(2)ATI]Sn-2 in excellent yield. The treatment of [(Me)(2)ATI]Sn-2 with GaI and InCl led to the bis(ligand)gallium(III) and -indium(III) compounds [(Me)(2)ATI]2GaI and [(Me)(2)ATI]2InCl. These metal complexes were characterized by elemental analysis, H-1 and C-13 NMR spectroscopy, and X-ray crystallography. All three metal adducts show fluxional behavior in solution at room temperature. [(Me)(2)ATI]Sn-2 exhibits a pseudo trigonal bipyramidal structure in the solid state. The gallium and indium atoms in [(Me)(2)ATI]2GaI and [(Me)(2)ATI]2InCl adopt trigonal bipyramidal geometry around the metal center with the halide occupying an equatorial site. A convenient, high-yield route to [(Me)(2)ATI]H is also reported. Crystal data with Mo K alpha (lambda = 0.710 73 Angstrom) at 183 K : [(Me)(2)ATI]Sn-2, C18H22N4Sn, a = 8.4347(11) Angstrom, b = 10.5564(13) Angstrom, c = 11.5527(11) Angstrom, alpha = 66.931(8)degrees, beta = 73.579(9)degrees, gamma = 67.437(7)degrees, V = 863.3(2) Angstrom(3), triclinic, space group P (1) over bar, Z = 2, R = 0.0224; [(Me)(2)ATI](2)Gal, C18H22GaIN4, a = 12.947(2) Angstrom, b = 9.5834(9) Angstrom, c = 16.0132(12) Angstrom, beta = 107.418(8)degrees, V = 1895.8(3) Angstrom(3), monoclinic, space group P2(1)/c, Z = 4, R = 0.0214; [(Me)(2)ATI]2InCl, C18H22ClInN4, a = 24.337(3) Angstrom, b = 8.004(2) Angstrom, c = 19.339(3) Angstrom, beta = 101.537(13)degrees, V = 3691.1(11) Angstrom(3), monoclinic, space group C2/c, Z = 8, R = 0.0224.