Synthesis of two new group 13 benzoato–chloro complexes: A structural study of gallium and indium chelating carboxylates

Abstract Two new heteroleptic chelated-benzoato gallium (III) and indium (III) complexes have been prepared and structurally characterized. The molecular structures of [GaCl 2 (4-Mepy) 2 (O 2 CPh)]·4-Mepy ( 1 ) and [InCl(4-Mepy) 2 (O 2 CPh)2]·4-Mepy ( 2 ) have been determined by single-crystal X-ray diffraction. The gallium compound ( 1 ) is a distorted octahedron with cis -chloride ligands co-planar with the chelating benzoate and the 4-methylpyridines trans to each other. This is the first example of a Ga(III) structure with a chelating benzoate. The indium compound ( 2 ) is a distorted pentagonal bipyramid with two chelating benzoates, one 4-methylpyridine in the plane and a chloride trans to the other 4-methylpyridine. The indium bis -benzoate is an unusual example of a seven-coordinate structure with classical ligands. Both complexes, which due to the chelates, could also be described as pseudo-trigonal bipyramidal, include a three-bladed motif with three roughly parallel aromatic rings that along with a solvent of crystallization and electron-withdrawing chloride ligand(s) stabilize the solid-state structures.