Pseudohalide complexes of trialkylgallium(III)

Abstract

Trimethyl- and triethyl-gallium(III) react with NMe₄X (X = CN, NCO, NCS, and N₃) to form well defined complexes of general formula NMe₄[R₃GaX](R = Me or Et) and, with the exception of X = NCO and NCS, NMe₄[(R₃Ga)₂X]. From i.r. and Raman spectra, it can be deduced that in the 1 : 1 [gallium(III) : pseudohalide] cyano-, cyanato-, and thiocyanato-complexes metal–pseudohalide bonding occurs between the gallium and carbon, the gallium and nitrogen, and the gallium and sulphur atoms respectively. The bonding between gallium and the cyanide ligand in the 2 : 1 complexes occurs through both the carbon and nitrogen atoms, whereas in the analogous azido-complexes, pseudohalide bonding to the metal occurs only through the α-nitrogen atoms.