Chemical modification of aluminium alkoxides for sol–gel processing

The chemistry of aluminium alkoxides and chemical modifications thereof by a variety of organic compounds, such as pyridine, aminoalcohols, beta -diketonic compounds or carboxylic acids, are reviewed. Special focus is put on structural aspects. Modification of aluminium alkoxides by organic ligands is of great importance for materials syntheses by sol-gel processing, because this allows adjusting the reactivity towards hydrolysis and condensation reactions and renders alumina-based inorganic-organic hybrid materials possible. Coordination, solvation and oligomerization have important influences on the structure and chemistry of the modified aluminium alkoxides, and organic side reactions, e.g. transesterification, have to be taken into account.