One of the most exciting research areas in materials chemistry today is to design hybrid materials with original properties [1] such as cooperative bifunctionality brought by each component. Indeed, the development of biopolymer/silica materials has become of great interest since 15 years [2,3]. In this work, our goal was to prepare highly porous chitosan-titania hybrid in order to improve the chemical stability of the materials under base catalytic conditions, taking into account the higher stability of titania compare to silica under these conditions [4]. Moreover the additional interest of such a material featuring both basic site (NH₂) and Lewis acidic site (Ti) concerns its potential for bifunctional catalytic applications. Titania/chitosan hybrid is obtained by a classical procedure³. The material was fully characterised (TGA, EDX, MET, SEM, adsorption/desorption of nitrogen (480 m²/g)).These materials were tested as catalyst for the monoglyceride formation which is of great industrial interest. It has been also tested on amine grafted on silica [5] and on chitosan/silica hybrid [6].

In conclusion, comparing with the results obtained with previous catalysts, chitosan/titania catalyst reveals better activity. In these conditions, reactions occur with high selectivity. The recycling of the catalyst shows no loss of activity. These unusual activity and selectivity may be rationalized by cooperative effect between organic and inorganic moieties. Other catalytic tests are under investigation.

[1] A. P. Wight, M. E. Davis, Chem. Rev.; 2002; 102 (10); 3589-3614.

[2] C. Sanchez, F. Ribot, New J. Chem.; 1994, 18, 987.

[3] K. Molvinger, F. Quignard, D. Brunel, M. Boissière, J.-M. Devoisselle, Chem. Mater.; 2004, 16, 3367.

[4] A. El Kadib, K. Molvinger, C. Guimon, F. Quignard, D. Brunel, Chem .Mat.; 2008, 20 (6), 2198-2204.

[5] A. Cauvel, G. Renard, D Brunel, J. Org. Chem.; 1997; 62 (3); 749-751.

[6] R. Valentin, K. Molvinger, F. Quignard, D. Brunel, New J. Chem.; 2003, 1690.

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