Bulky amidinato complexes and amidine adducts of Al, Ga and In halides

Abstract

Reactions of a series of bulky amidinate salts M[RC(NAr) 2] (M = Li, Na or K; R = H, Fiso; Me, Aiso; Bu t , Piso; Ar = 2 , 6 - Pr 2 i C 6 H 3 ) with group 13 halides are reported. Treatment of the metal(I) halides, ‘GaI’ or InCl, with [Li(Fiso)] led to disproportionation reactions which gave the first gallium(II)-amidinate complex, [{GaI(Fiso)} 2] ( 7), in addition to the metal(III) complexes, [GaI(Fiso) 2] ( 8) and [InCl(Fiso) 2] ( 10). Moreover, the Ga(II) compounds 7 and [{GaI(Piso)} 2] ( 9) were synthesised in metathesis reactions between amidinate salts and [{GaI 2(NHCy 2)} 2] (Cy=cyclohexyl). Treating [AlMe 2(Aiso)], [{AlH 2(Piso)} 2] or [AlMe 2(Piso)] with iodine in toluene led to isolation of the Al(III) iodide complexes [AlI 2(Aiso)] ( 12), [AlI 3(AisoH)] ( 13) and [AlI 2(Piso)] ( 14). The adduct [GaCl 3(FisoH)] ( 16) was obtained from the reactions of either [Na(Fiso)] or FisoH with GaCl 3, whilst the amidinium salt [TripH 2][InBr 4] ( 17), (Trip = [TrC(NPr i ) 2] −, Tr = 9-triptycenyl) was isolated from the reaction of [Li(Trip)] with InBr 3. The X-ray crystal structures of 7, 9, 10, 13, 14, 16 and 17 are reported.