The reaction of Me3In and ROH (R = CH2CH2NMe2, CH(CH3)CH2NMe2, C(CH3)2CH2OMe, CH2CH2OMe) in toluene under aerosol assisted chemical vapor deposition (AACVD) conditions leads to the production of indium oxide thin films on glass. The indium oxide films were deposited at 550 degrees C and analyzed by scanning electron microscopy (SEM), X-ray powder diffraction, wavelength dispersive analysis of X-rays (WDX), X-ray photoelectron spectroscopy (XPS), and Raman spectroscopy. This CVD technique offers a rapid, convenient route to In2O3, which presumably involves the in situ formation of dimethylindium alkoxides, of the type [Me2InOR]2. In order to identify compounds present in the aerosol mist, the solution-phase reaction between Me3In and ROH (R = CH2CH2NMe2, C(CH3)2CH2OMe, CH(CH3)CH2NMe2, CH(CH2NMe2)2) at room temperature in toluene was carried out. Dimeric indium alkoxides, of the type [Me2In(OR)]2, were isolated, and their structures were determined by X-ray crystallography.

Thin films of Ga(2)O(3) have been produced from [Ga(NMe(2))(3)](2) and ROH (R = CH(2)CH(2)NMe(2), CH(CH(2)NMe(2))(2), CH(CH(3))CH(2)NMe(2), CH(2)CH(2)OMe and C(CH(3))(2)CH(2)OMe) by aerosol assisted chemical vapour deposition on glass. Transparent, unreflective films were obtained at a deposition temperature of 550 degrees C using toluene as solvent. The gallium oxide films were analyzed by Scanning electron microscopy (SEM), Raman spectroscopy, wavelength dispersive analysis of X-rays (WDX) and X-ray photoelectron spectroscopy (XPS). The gallium oxide films obtained were X-ray amorphous. Gas-sensing experiments indicated that the films showed an n-type response to ethanol at a variety of temperatures.

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The donor-functionalised alkoxides [Et(2)Ga(OR)](2)(R = CH(2)CH(2)NMe(2)(1), CH(CH(2)NMe(2))(2)(2), CH(2)CH(2)OMe (3), CH(CH(3))CH(2)NMe(2)(4), C(CH(3))(2)CH(2)OMe (5)) were synthesised by the 1:1 reaction of Et(3)Ga with ROH in hexane or dichloromethane at room temperature. Reaction of Et(3)Ga with excess ROH in refluxing toluene resulted in the isolation of a 1:1 mixture of [Et(2)Ga(OR)](2) and the ethylgallium bisalkoxide [EtGa(OR)(2)](R = CH(2)CH(2)NMe(2)(6) or CH(CH(3))CH(2)NMe(2)(7)). X-ray crystallography showed that compound 6 is monomeric and this complex represents the first structurally characterised monomeric gallium bisalkoxide. Homoleptic gallium trisalkoxides [Ga(OR)(3)](2) were prepared by the 1:6 reaction of [Ga(NMe(2))(3)](2) with ROH (R = CH(2)CH(2)NMe(2)(8), CH(CH(3))CH(2)NMe(2)(9), C(CH(3))(2)CH(2)OMe (10)). The decomposition of compounds 1, 4, 5 and 8 were studied by thermal gravimetric analysis. Low pressure CVD of 1 and 5 resulted in the formation of thin films of crystalline Ga(2)O(3).

Homoleptic gallium tris(alkoxides) [Ga(OR) 3 ] 2 were prepared by the reaction of [Ga(NMe 2 ) 3 ] 2 (1) and excess ROH (R = CH 2 CH 2 NMe 2 (2), CH(CH 3 )CH 2 NMe 2 (3), C(CH 3 ) 2 CH 2 OMe (4), CH 2 CH 2 OMe (5)) in toluene at room temperature. Compounds 2-5 were isolated as colourless oils. The side-products, [Ga(OCH 2 CH 2 NMe 2 ) 2 Cl] ( 6), [Ga(OCH(CH 3 )CH 2 NMe 2 ) 2 Cl] ( 7) and [Ga(OC(CH 3 ) 2 CH 2 OMe)Cl 2 ] 2 (8) were also isolated in low yield during the synthesis of 2, 3 and 4, respectively. However, compounds 6 and 7 were also prepared directly from the reaction of [Ga(NMe 2 ) 2 Cl] and 2 equivalents of ROH (6, R = CH 2 CH 2 NMe 2 ; 7, R = CH(CH 3 )CH 2 NMe 2 ). Similarly, compound 8 was isolated from the reaction of [Ga(NMe 2 )Cl 2 ] and 1 equivalent of HOC(CH 3 ) 2 CH 2 OMe. Single crystal X-ray crystallography showed that the gallium bis(alkoxides) (6 and 7) are monomeric in the solid state with the gallium centre adopting a distorted trigonal bipyramidal geometry. In contrast, the gallium mono(alkoxide) 8 is dimeric.