Templated non-hydrolytic synthesis of mesoporous zirconium silicates and their catalytic properties

A novel non-hydrolytic sol-gel (NHSG) synthesis of mesoporous zirconium silicate xerogels is presented. The condensation between silicon acetate, Si(OAc)(4), and Zr(NEt2)(4) resulting in acetamide elimination leads to homogeneous zirconium silicate xerogels containing Si-O-Zr linkages. The addition of Pluronic P123 template provides stiff gels that are after template removal by calcination at 500 A degrees C in air converted to stable mesoporous xerogels with wormhole-type pores, high surface area over 500 m(2) g(-1), and tetrahedrally coordinated Zr atoms in the framework. The composition and morphology of the xerogels, volatile reaction byproducts, and thermal transformations were followed by elemental analysis, IR spectroscopy, thermal analysis TG-DSC, nitrogen adsorption, C-13 and Si-29 solid-state NMR spectroscopy, DRUV-Vis spectroscopy, SAXS, and HT powder XRD. These potential catalysts were tested for the Meerwein-Ponndorf-Verley reduction of 4-tert-butylcyclohexanone and for aminolysis of styrene oxide with aniline. Resulting reaction systems display good activity and selectivity.