Organically Modified Metal Alkoxide Precursors

In many sol-gel protocols, metal alkoxides are reacted in situ with chelating organic ligands. Despite the fact that substituting one or more OR groups by such ligands has huge impact on the formation, structure and properties of the derived gels, the organically modified derivatives were rarely isolated or characterized. The goal of the project is to gain deeper insight into the basic reactivity and structural chemistry of organically modified metal alkoxides. The key issues to be investigated will be (i) the basic chemistry of organically modified metal alkoxides with focus on rarely used but promising ligands (such as oximes, hydroxamic acids, amino acids, ß-ketoimines or oxine derivatives) and a range of different metal alkoxides, (ii) the hydrolysis reactions of such derivatives by isolating and structurally characterizing partially hydrolyzed compounds and spectroscopic in-situ investigation of the hydrolysis reactions, and (iii) preparation on metal alkoxide derivatives with various functional organic ligands. The vision is that it may be possible in the future to design sol-gel materials by assembling tailor-made molecular building blocks in a rational way to achieve a particular set of materials properties. In order to do so, a collection of different building blocks with different shapes (structures), functionalities, connectivities, etc. must be readily available and their reactivity must be mastered. The knowledge gained in the project will be a step forward in this direction.

In many sol-gel protocols, metal alkoxides are reacted in situ with chelating organic ligands. Despite the fact that substituting one or more OR groups by such ligands has huge impact on the formation, structure and properties of the derived gels, the organically modified derivatives were rarely isolated or characterized. The goal of the project is to gain deeper insight into the basic reactivity and structural chemistry of organically modified metal alkoxides. The key issues to be investigated will be (i) the basic chemistry of organically modified metal alkoxides with focus on rarely used but promising ligands (such as oximes, hydroxamic acids, amino acids, ß-ketoimines or oxine derivatives) and a range of different metal alkoxides, (ii) the hydrolysis reactions of such derivatives by isolating and structurally characterizing partially hydrolyzed compounds and spectroscopic in-situ investigation of the hydrolysis reactions, and (iii) preparation on metal alkoxide derivatives with various functional organic ligands. The vision is that it may be possible in the future to design sol-gel materials by assembling tailor-made molecular building blocks in a rational way to achieve a particular set of materials properties. In order to do so, a collection of different building blocks with different shapes (structures), functionalities, connectivities, etc. must be readily available and their reactivity must be mastered. The knowledge gained in the project will be a step forward in this direction.