Monoorgano-gallium and –indium complexes derived from dianionic tridentate ONO Schiff bases: Synthesis, crystal structures and photoluminescence

Abstract Reactions of triorgano-gallium and –indium etherates with N′-(2-hydroxybenzylidine)benzohydrazide and N′-(2-hydroxy-3-methoxybenzylidine)benzohydrazide in refluxing benzene afforded complexes of composition [{RM}{–O(C 6 H 3 R′-3)CH N–N C(C 6 H 5 )O–}] (M Ga, In; R Me, Et; R′ H, OMe). These complexes have been characterized by elemental analysis, IR, UV-vis, and NMR ( 1 H and 13 C{ 1 H}) spectroscopy. The molecular structures of [{MeGa}{–O(C 6 H 4 )CH N–N C(C 6 H 5 )O–}] 2 ( 1 ), [{MeGa}{–O(C 6 H 3 –OMe)CH N–N C(C 6 H 5 )O–}] 2 ( 2 ) and [{EtGa}{–O(C 6 H 3 –OMe)CH N–N C(C 6 H 5 )O–}] 2 ( 6 ) were established by X-ray crystallography. These complexes adopt a dimeric structure with phenolate oxygen bridges with the gallium atom acquiring a distorted square pyramidal configuration. These complexes are emissive in toluene solution at room temperature.