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

Abstract

The preparation and crystal structures of the first examples of gallium halide complexes with the tripodal arsine, MeC(CH₂AsMe₂)₃, reveal three distinctly different coordination modes for the ligand; the neutral [{µ₃-MeC(CH₂AsMe₂)₃-κAs:κAs′:κAs″}(GaI₃)₃] with the triarsine coordinating to three GaI₃ units, [{Me₂AsCH₂C(Me)(CH₂AsMe₂)₂-κ²AsAs′}GaCl₂][GaCl₄] involving bidentate chelation to a GaCl₂⁺ cationic unit with the third As donor atom uncoordinated, and [{MeC(CH₂AsMe₂)₃-κAs:κ²As′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.