Binuclear alkylmetallane dioldiates tBu4M2(diol–(H))2 (M=Al, Ga) and their reactions with aluminium- and gallium trialkyls

Reactions of 1,2-di(hydroxymethyl)benzene with tBu3M (M=Al, Ga) yield binuclear compounds [tBu4M2(OCH2C6H4CH2OH)2], M=Al (1) and M=Ga (2) respectively. Compounds 1 and 2 as bifunctional (two OH groups), tetradentate (4O) ligands react with aluminium- and gallium trialkyls with formation of trinuclear products [tBu4XM3(OCH2C6H4CH2O)2] [M=Al, X=tBu (3); M=Ga, X=tBu (4); M=Ga, X=Me (6)]. The transmetalation reaction of the compound 6 with one equivalent of Me3Ga causes the exchange of tBu2Ga unit and formation of the new mixed-ligand compound tBu2Me3Ga3(OCH2C6H4CH2O)2 (7). The transmetalation reaction is considered as a method of synthesis of mixed-ligand and mixed-metal complexes of Group 13 alkyls with multidentate ligands. The molecular structures of Me5Al3(OCH2C6H4CH2O)2 (5), 6 and 7 have been determined by X-ray crystallography.