Effect of irradiation intensity on rate and selectivity of photosensitized oxidation of dibutyl sulfide over C₇₀ fullerene

Photoinitiated oxidation of dibutyl sulfide (DBS) with air oxygen in a toluene solution of C₇₀ fullerene during irradiation with visible light at a wavelength of 500-700 nm results in the formation of dibutyl sulfone as a main detected product, dibutyl sulfoxide, and butanal. A change in the intensity of radiation incident on the reaction mixture from 2.2 to 44 mW/cm² insignificantly increases the quantum efficiency of the DBS consumption from 4.5 to 5.9%. The selectivity for sulfoxide increases during the process, while selectivity for sulfone decreases.