Syntheses and structures of the heterometallic complexes [{MeIn(μ-PCy)}2(μ-PCy)]2(Li · Et2O)4, [Me2In(PhMes)2]−[Li(TMEDA)2]+ and [Me2(PHMes)2In]−[K(PMDETA)2]+ [Cy = cyclohexyl, Mes = 2,4,6-Me3C6H2, TMEDA = (Me2NCH2)2, PMDETA = (Me2NCH2CH2)2NMe]

The reaction of CyPHLi (Cy = cyclohexyl) with InMe3 in Et2O gives the heterometallic cage [{MeIn(μ-PCy)}2(μ-PCy)]2(Li · Et2O)4 (1), containing the heterometallic tetraanion View the MathML source[{MeIn(μ-PCy)}2(μ-PCy)]24-. In contrast, similar reactions of InMe3 with MesPHM (M = Li, K) in the presence of the Lewis bases TMEDA and PMDETA give [Me2In(PhMes)2In]−[Li(TMEDA)2]+ (2) and [Me2(PHMes)2In]−[K(PMDETA)2]+ (3), respectively. The formation of [Me2(PHMes)2In]− anions in these complexes provides key evidence of the mechanism of formation of the metallocyclic tetraanion of 1.