Assisted Oxidations with Sacrificial Use of an Aldehyde

Metal-Assisted Oxidations with Sacrificial Use of an Aldehyde 

Under similar conditions, ketones in the reaction mixture are converted to esters via B aeyer-Villiger oxidation with in situ formed peracid, or thioethers can be converted to the sulfoxides or sulfones. 

Metals can play a clear but small role in such epoxidations or esterifications with a sacrificial aldehyde. First, it has long been known that the free radical aldehyde autoxidation can be initiated and therefore accelerated by metal ions. For instance, high concentrations of peracid can be obtained with dissolved Fe catalysts (5). As a rule, the presence of a metal allows autoxidation at considerably lower temperature than for the noninitiated reaction. The exact nature of the metal is not critical. Second, epoxidations by a peracid may be metal centered however, at the typical temperatures of the Mukuyiama epoxidation, the uncatalyzed reaction of peracid and olefin is usually fast enough to make the metal redundant for this second step. 

A large number of anchored metals have been proposed as catalysts or, more correctly, initiators for the olefin epoxidation or other oxidations under 

Supported Initiators of Oxidations with O2 and a Sacrificial Aldehyde 

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