Intramolecularly stabilized organoaluminium and organogallium compounds: synthesis and X-ray crystal structures of some dimethylaluminium and -gallium alkoxides Me2MOROR′ and amides Me2MNHROR′

The intramolecularly stabilized dimeric organoaluminium and organogallium alkoxide complexes [(CH3)2Al(μ-OROR′)]2 (R/R′ = CH2CH2/C6H5 (1a) CH(CH3)CH2/CH3 (2a), CH2CH2C(CH3)2/CH3 3a), CH2C6H4-2/CH3 (4a), C6H4-2/CH3 (5a), C6H4-2/C2H5 (6a), C6H3-4-CH3-2/CH3 (7a), [(CH3)2Ga(μ-OROR′)]2 (R/R′ = CH(CH3)CH2/CH3 (2b), CH2CH2C(CH3)2/CH3 (3b), CH2C6H4-2/CH3 (4b), C6H4-2/CH3 (5b), C6H4-2/C2H5 (6b), CH2CH2/CH3 (8b),, [(CH3)2Al(μ-NHROR′)]2 (R/R′ = CH2CH2/CH3 (9a) and CH2CH2CH2/CH3 (10a)) have been synthesized from trimethylaluminium or trimethylgallium and the corresponding alkoxy alcohols. Trimethylgallium reacts with CH3OCH2CH2NH2 and CH3OCH2CH2CH2NH2 with formation of the 1:1 adducts 11b and 12b, which decompose above 110 °C to yield CH4 as well as [(CH3)2Ga(μ-NH(CH2)2OCH3)]2 (9b) and [(CH3)2Ga(μ-NH(CH2)3OCH3)]2 (10b) respectively. The 1H-, 13C-NMR and mass spectra of the new compounds, as well as the X-ray crystal structure analyses of 2b, 4a, 5a, 5b, 8b, and 12b, are reported and discussed.