Synthesis of the Sterically Related Nickel Gallanediyl Complexes [Ni(CO)3(GaAr′)] (Ar′ = C6H3-2,6-(C6H3-2,6-iPr2)2) and [Ni(CO)3(GaL)] (L = HC[C(CH3)N(C6H3-2,6-iPr2)]2): Thermal Decomposition of [Ni(CO)3(GaAr′)] to give the Cluster [Ni4(CO)7(GaAr′)3]

Reaction of Ni(CO)(4) in toluene at room temperature with one equivalent of GaAr' (Ar' = C6H3-2,6-(C6H3-2,6-iPr(2))(2)) and GaL (L = HC[C(Me)N(C6H3-2,6-iPr(2))](2)) formed the mono-substituted Ni(CO)(3)(GaAr') (1) and Ni(CO)(3)(GaL) (3), respectively. Compound 1 decomposed under reduced pressure or upon heating in toluene to give the new cluster species Ni-4(CO)(7)(GaAr')(3) (2). Reaction of 3 with a second equivalent of GaL in toluene at 95 degrees C afforded the disubstituted complex Ni(CO)(2)(GaL)(2) (4). All the compounds were characterized by IR, H-1 and C-13{H-1} NMR spectroscopy and X-ray crystallographic studies were undertaken to elucidate the structures of the complexes 2,3 and 4.