Mononuclear gallium(III) complexes based on salicylaldoximes: Synthesis, structure and spectroscopic characterization

The reactions of Ga(acac)3 with salicylaldoxime (saoH2) and methyl-salicylaldoxime (Me-saoH2) in dichloromethane/hexane afforded the complexes [Ga(acac)(saoH)2] (1) and [Ga(acac)3][Ga(acac)(MesaoH)2] (2), respectively, in high yields. The crystal structures of 1 and 2 have been determined by single-crystal X-ray crystallography. Both complexes are mononuclear with the Ga(III) atoms being in octahedral environments surrounded by two bidentate chelate R-saoH− and one bidentate chelate acac− ligands. A [Ga(acac)3] moiety has co-crystallized along with the methylsalicylaldoximato complex. Characteristic IR as well as NMR data are discussed in terms of the nature of bonding in the structures of the two complexes. 1H and 13C NMR data in CDCl3 indicate that the salicylaldoximato complexes isomerize in solution.

Graphical abstractThe reactions of Ga(acac)3 with salicylaldoxime (saoH2) and methylsalicyladoxime (MesaoH2) resulted in two mononuclear complexes with the general formula [Ga(acac)(RsaoH)2]. The structures of both complexes were determined with single-crystal X-ray crystallography. Both complexes were also characterized by IR, 1H and 13C NMR spectroscopy.Figure optionsDownload full-size imageDownload as PowerPoint slide