S -Aryl dibenzothiophenium salts, obtained through a highly regioselective C–H sulfenylation of o -benzyl-protected phenols, are used as precursors of 6 H -benzo[ c ]chromenes. The reaction starts with a photocatalytically triggered single-electron transfer to the sulfonium salt, which promotes the formation of an aryl radical via selective mesolitic cleavage of the S–Ar exo bond. Mechanistic studies reveal that this initial radical species cyclizes following a kinetically favored 5-exo-trig pathway. Subsequent ring expansion, favored by rearomatization, delivers the desired tricyclic systems.