Selective photocatalytic oxidation of alcohols to aldehydes and ketones by nitromethane on titanium dioxide under light irradiation

The oxidation of alcohols to aldehydes and ketones is one of the most important transformations in organic chemistry both in laboratory and industrial scale, because the corresponding carbonyl compounds are valuable compounds such as pharmaceuticals, agricultural chemicals and fine chemicals[1-2]. Photocatalytic reactions using semiconductor nanomaterials have attracted much attention. One of the most promising semiconductors for photocatalytic applications is titanium dioxide. The reasons for its widespread are due to its low price, chemical and thermal stability, large commercially availability [3]. In this study, for the first time, nitroalkanes, especially nitromethane, have been used as an electron acceptor for the oxidation of alcohols in the presence of TiO2 photocatalyst. The reactions showed excellent selectivity for production of aldehydes. In the case of the use of larger nitroalkanes, the imine product, which is the result of the reaction of aldehyde with aliphatic amine, is also produced and TiO2 showed high reusability in this reaction.