Organic sulfides photooxidation using sensitizers covalently grafted on silica : towards a more efficient and selective solar photochemistry

A visible light sensitized oxidation of organic sulfides using a derivative of 9,10 dicyanonoanthracene (DCA) covalently grafted on silica (DCAC–Si) is studied. The reaction is more efficient than the corresponding homogeneous reaction and some improvement in the rate of product formation is noticed. These observations are discussed. In the case of di n-butylsulfide, the sulfoxide/(sulfone + disulfide) selectivity is increased. Diphenyl sulfide leads selectively and efficiently to diphenylsulfoxide. Advantages of the process, using reusable sensitizer and solar light are emphasized.