Photochemistry of substituted dibenzothiophene oxides: The effect of trapping groups

Photolyses of dibenzothiophene sulfoxides (DBTOs) with intramolecular trapping functionalities attached in the 4-position show higher quantum yields of deoxygenation. Deoxygenation quantum yields are also less solvent dependent for the substituted DBTOs. Product analysis shows a detectable amount of intramolecular O-trapped products and suggests that solvent effects observed in previous studies of DBTO derive at least mainly from the reactivity between the oxidizing species that is released, presumably O(P-3), and the solvent, rather than from other macroscopic solvent parameters.