Ormosil-TEMPO

Ormosil-TEMPO is a sol-gel hydrophobized nanostructured silica matrix... 

In other cases, organic modification of the sol gel cages markedly protects the entrapped molecular dopant from degradation by external reactants, as shown for instance by the entrapment of the radical 2,2,6,6-tetramethylpiperidine-l-oxyl (TEMPO). This is a highly active catalyst which in the NaOCl oxidation of alcohols to carbonyls in a CH2CI2-H20 biphasic system becomes highly stabilized upon sol gel entrapment in an ORMOSIL matrix it progressively loses it activity when entrapped at the external surface of commercial silica.25... 

Figure 5.13 Yields in the Montanari-Anelli oxidation of 1-nonanol to give nonanal in the presence of silica-supported TEMPO (SG-TMP-O, front row), and in the presence of sol gel ORMOSIL doped with TEMPO [SG-TEMPO-1 is 25% and SG-TEMPO-2 is 100% methylated (middle and back row, respectively)]. (Reproduced from ref. 25, with permission.)...

R. Ciriminna, C. Bolm, T. Fey and M. Pagliaro, Sol-Gel Ormosils Doped with TEMPO as Recyclable Catalysts for the Selective Oxidation of Alcohols, Adv. Synth. Catal., 2002, 344, 159. 

Ciriminna, R., Bolm, C., Fey, T., and Pagliaro, M. (2002) Sol-gel Ormosils doped with TEMPO as recyclable catalysts for the selective oxidation of alcohols. Adv. Synth. Catal, 344 (2), 159-163. 

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