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U. Schubert, U. Bauer, H. Fric, M. Puchberger, W. Rupp, V. Torma:
"Modification of Metal Alkoxide Precursors by Organofunctional Bidentate Ligands: Chemical Problems and Opportunities for Materials Syntheses";
Mat. Res. Soc. Symp. Proc., 847 (2005), 533 - 539.

Bidentate ligands are potentially useful to modify metal alkoxides precursors for sol-gel processing. However, anionic bidentate ligands are needed to get a strong coordination, while diamines as neutral bidentate ligand form coordination polymers [Ti₂(OR)₈(diamine)₂]_oo when reacted with Ti(OR)₄. The Lewis acidity of metal alkoxides may cause organic side reactions. The first is the formation of ester and water in the reaction with carboxylic acids, and therefore carboxylate-substituted metal oxide clusters of the general composition M_nO_x(OH/OR)_y(OOCR)_z, are obtained instead of substituted monomeric precursors. The second side reaction discussed is the cleavage of ß-diketones by metal alkoxides. Despite this side reaction, 3-acetyl-6-trimethoxy-silyl-hexane-2-one is a useful compound to prepare single-source precursos for silica/metal oxide composites.

http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC05937116