Chemistry of Oxo-alkoxides of Metals

摘要

In view of the extremely high ease of hydrolysis of metal alkoxides by even traces of moisture from any source (atmosphere, solvents, equipment, etc.), stringent precautions for maintenance of anhydrous environmental conditions have generally been regarded as essential for the synthesis of simple binary or heterometallic alkoxides in a pure state. However, from the 1950s, this facile hydrolytic susceptibility has been increasingly utilised in the sol-gel technique: the conversion of a metal alkoxide dissolved in an organic solvent (generally the parent alcohol) into a hydroxo-oxo-alkoxide 'sol,' followed by gelation and sintering to give the desired ceramic material. This development has led to much interest in the mechanism of the hydrolysis process and also in the actual composition of the hydroxo- or oxo-alkoxide derivatives formed. Early investigations by Bradley et al. have been summarised.