Diorgano-gallium and -indium complexes with N-heterocyclic carboxylic acids: Synthesis, characterization and structures of [Me 2M(O 2C–C 5H 4N)] 2, M = Ga or In

Abstract

The reaction of triorgano-gallium and -indium etherate with heterocyclic carboxylic acids in benzene at room temperature yields complexes of the type [R 2M(L)] n (M = Ga or In; R = Me or Et; L = 2-(C 5H 4N)CO 2, 2-(C 4H 3N 2)CO 2 or 2-(C 9H 6N)CO 2). These complexes have been characterized by elemental analysis, IR, UV–vis, NMR ( 1H and 13C{ 1H}) and mass spectral data. Complexes with L = (C 5H 4N)CO 2- and (C 9H 6N)CO 2- showed photoluminescence on excitation with ∼250 or ∼310 nm radiation, respectively. Single crystal X-ray structural analysis of [Me 2M(O 2C–C 5H 4N-2)] 2 (M = Ga or In), revealed a dimeric structure with five-coordinate metal atoms arising from the presence of two tridentate bridging picolinate ligands.