Synthesis and characterisation of modified germanium (IV) isopropoxide with internally functionalised oximes: soft transformation of some of these to pure nano-sized germania

摘要

Reactions of [Ge(OPri)4] with internally functionalised oximes in 1:1 and 1:2 molar ratios in refluxing anhydrous benzene yielded complexes of the type [Ge(OPri)4-n{ONC(CH3)C4H3O-2}n] (1, 2); [Ge(OPri)4-n{ONC(CH3)C4H3S-2}n] (3, 4); [Ge(OPri)4-n{ONC(CH3)C5H4N-2}n] (5, 6); [Ge(OPri)4-n{ONC(H)C4H3O-2}n] (7, 8); [Ge(OPri)4-n{ONC(H)C4H3S-2}n] (9, 10); [Ge(OPri)4-n{ONC(H)C5H4N-2}n] (11, 12) (where n = 1 or 2), All the above monomeric complexes are soluble in organic solvents and have been characterised by elemental analyses and spectroscopy. Thermal and hydrolytic studies of complexes 2, 4 and 8 suggest them to be potential molecular precursors for the synthesis of pure GeO2 at low temperatures by the sol-gel technique. Powder X-ray diffraction, IR spectral studies as well as SEM images of the GeO2 indicate formation of pure nano-crystalline hexagonal (α-quartz) germania at 550°C.