Phosphonates hybrid materials

Lin and coworkers have reported zirconium phosphonate-derived Ru-BINAP systems (Scheme 16) [49]. Zirconium phosphonate-based chiral porous hybrid materials containing the Ru(BINAP)(diamine)Cl2 precatalysts showed excellent enantioselectivity (up to 99.2% ee) in the asymmetric hydrogenation of aromatic ketones. These catalysts were also readily recovered by centrifugation and reused for up to 10 times without significant loss of catalyst activity and enantioselectivity. Related zirconium phosphonates containing Ru(BINAP)(DMF)2Cl2 precatalysts were successfully used for asymmetric hydrogenation of p-keto esters with up to 95% ee [50]. 

Mehring M., Lafond V, Mutin P.H., Vioux A. New sol-gel routes to organic-inorganic hybrid materials modification ofmetal alkoxide by phosphonic or phosphinic acids. J. Sol-Gel Sci. Tech. 2003 26 99-102... 

Substituting a certain part of the alkoxidic groups by nonhydrolysable ones, such as alkyl groups in the case of alkoxysilanes or phosphonic acid in the case of metal alkoxides, organically modified oxides, i.e. inorganic-organic hybrid materials, have been prepared. 

Li, S., Zhou, Z., Abernathy, H., Liu, M., Li, W, Ukai, J., Hase, K. and Nakanishii, M. 2006. Synthesis and properties of phosphonic acid-grafted hybrid inorganic-organic polymer membranes. Journal of Materials Chemistry 16 858-864. 

Binsu VV, Nagarale RK, Shahi VK (2005) Phosphonic acid functionalized aminopropyl triethoxysilane-PVA composite material organic-inorganic hybrid proton-exchange membranes in aqueous media. J Mater (Them 15 4823 831... 

---