Structural diversity in gallium(III) complexes of the tripodal triarsine MeC(CH2AsMe2)3

The preparation and crystal structures of the first examples of gallium halide complexes with the tripodal arsine, MeC(CH(2)AsMe(2))3, reveal three distinctly different coordination modes for the ligand; the neutral {micro(3)-MeC(CH(2)AsMe(2))3-kappaAs:kappaAs':kappaAs'}(GaI(3))3] with the triarsine coordinating to three GaI(3) units, {Me(2)AsCH(2)C(Me)(CH(2)AsMe(2))2-kappa(2)AsAs'}GaCl(2)]GaCl(4)] involving bidentate chelation to a GaCl2+ cationic unit with the third As donor atom uncoordinated, and {MeC(CH(2)AsMe(2))3-kappaAs:kappa(2)As'As'}(GaCl3)(GaCl2)]GaCl4] in which the triarsine forms a bidentate chelate to the GaCl2+ unit and the third As donor atom binds to a further GaCl3 unit.