Photochemistry of substituted dibenzothiophene oxides: the effect of trapping groups.

[reaction: see text] 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((3)P), and the solvent, rather than from other macroscopic solvent parameters.