The group 13 monoalkoxometallanes [Me2Ga(OC(CH3)2CH2OMe)]2 (1) and [Me2In(OCH(CH3)CH2OMe)]2 (2), incorporating donor functionalised alkoxides, were synthesised from the reaction of GaMe3 or InMe3 with ROH (R = C(CH3)2CH2OMe (1); R = CH(CH3)CH2OMe (2)) in toluene. X-ray crystallography showed that both compounds adopt dimeric structures with a planar M2O2 ring, and each group 13 atom is coordinated in a distorted trigonal bipyramidal geometry. The AACVD reaction of GaMe3 and ROH (R = C(CH3)2CH2OMe, CH2CH2OMe, CH2CH2NMe2) resulted in the formation of thin films of Ga2O3 on glass substrates at 450 • C. The gallium oxide films were analyzed by scanning electron microscopy, X-ray powder diffraction, energy dispersive analysis of X-rays, wavelength dispersive analysis of X-rays and X-ray photoelectron spectroscopy. This CVD technique offers a rapid, convenient route to Ga2O3, which involves the in situ formation of dimethylgallium alkoxides, of the type [Me2Ga(µ-OR)]2 similar to compound 1.