New types of base-stabilized alkyl aluminum, gallium, and indium complexes

Novel dinuclear metal complexes with the general formula [(Me2M){NC5H4 C(R) NNC6H5}-(MMe3)] (M = Al, R = CH3 (1); M = Ga, R = CH3 (2); M = Al, R = H (3 ); M = Ga, R = H (4)) result when 2-pyridinecarboxaldehyde phenyl hydrazone ligands are mixed with trimethylaluminum and -gallium. The decagallium com plex (GaMe2)(8)(GaMe)(2)(mu(4)-O)(2)(mu(3)-O)(4)(C12H10N3)(2) (5) was isola ted during the synthesis of 4 as a minor orange product. Three dinuclear me tal compounds of the general formula [(Me2M)(SC4H3CHNNC6H5)](2) (M = Al (6) ; M = Ga (7); M = In (8)) were synthesized by the methane elimination react ion of thiophenecarboxaldehyde phenylhydrazone with trimethyl aluminum, -ga llium, and -indium. The mu(4)-oxo complex [(Me2In)(2)(OC4H3CH NNC6H5)](2)O (9) was prepared via the reaction of furancarboxaldehyde phenylhydrazone wi th trimethylindium. The X-ray crystal structures of 1, 4, 5, 7, and 9 are d escribed. The structural data revealed that 5 is a decanuclear gallium comp ound that contains an eight-membered Ga4O4 cyclic core and that 9 is a tetr anuclear indium compound with a weak interaction between the pendant furan and the indium center.