Sol-gel immobilized aryl iodides for the catalytic oxidative α-tosyloxylation of ketones

New hybrid silica materials M1-M4, derived from mono and bis-silylated aryl iodides, have been prepared via sol-gel processes, either by the hydrolytic polycondensation of a bis-silylated monomer or by the co-gelification of a monosilylated precursor with tetraethylorthosilicate. They have been fully characterized by elemental analysis, 13C and 29Si CP-MAS solid state NMR, IR, TGA, and nitrogen-sorption measurements. These organosilicas have been successfully applied as supported catalysts in the α-tosyloxylation of aliphatic ketones in the presence of m-chloroperbenzoic acid (m-CPBA) as an oxidant, with the corresponding α-tosyloxyketones obtained in moderate to good isolated yields. The recyclability of the supported catalysts by a simple filtration has also been investigated.