Structural insight on organosilica electrodes for waste-free alcohol oxidations
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Organic modification of sol–gel catalytic glassy electrodes made of a thin layer of organosilica doped with nitroxyl radical TEMPO (2,2,6,6-tetramethyl-1-piperidinyloxy) crucially enhances stability in the waste-free oxidation of alcohols to carbonyls in water. Structural comparison between analogous films made of organosilica and unmodified SiO2 shows that the origin of the pronounced stable activity of the ORMOSIL film lies in high hydrophobic and also in the pronounced low degree of hydrophilicity.
Keywordssol–gel anodic oxidation TEMPO alcohols green chemistry
Financial support from the Quality College del Cnr is gratefully acnkowledged. Thanks to François Béland and Annie Michaud of SiliCycle Inc. (Quebec City, Canada) for fruitful collaboration, which recently led to commercialization of the SiliaCatTEMPO catalyst series.
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