Baeyer-Villiger oxidation of ketones catalyzed by iron(III) meso-tetraphenylporphyrin chloride in the presence of molecular oxygen

Abstract

Efficient selective oxidation of ketones to lactones by molecular oxygen with benzaldehyde as an oxygen acceptor, in the presence of metalloporphyrins, has been reported. Iron(III) meso-tetraphenylporphyrin chloride ( Fe ( TPP ) Cl ) showed excellent activity and selectivity for oxidation of cyclohexanones under mild conditions. Moreover, different factors influencing ketones oxidation, e.g. catalyst, solvent, temperature and additive, have been investigated. The turnover number (TON) of the Fe ( TPP ) Cl catalyst could reach up to 71000 in a large scale oxidation of cyclohexanone. A plausible mechanism of ketone oxidation by molecular oxygen in the presence of metalloporphyrins and benzaldehyde was proposed.