Chemistry of (tetramethylcyclopentadienyl)gallium(III) compounds

Two tetramethylcyclopentadienyl gallium(III) compounds Ga(C5Me4H)3 and Cl2(C5Me4H)Ga·pyridine have been prepared and characterized. In contrast, when the syntheses of Ga(C5Me4H)2Cl, Ga(C5Me4H)Cl2 and Me2Ga(C5Me4H) were attempted by metathetical and/or ligand redistribution reactions, the isolated product in each case was a mixture of chemically related compounds rather than single species. When pyridine was added to a solution prepared by combining Ga(C5Me4H)3 and GaCl3 in a 1:2 mol ratio in diethyl ether, the product was the adduct Cl2(C5Me4H)Ga·pyridine, a yellow–green crystalline solid. An elemental analysis, 1H- and 13C-NMR spectra and an X-ray structural study confirmed the identity of this gallium–nitrogen adduct.