Chemistry Letters, Vol.49, No.7, 753-756, 2020
Synthesis of Thioxanthones through Formal C-H Thiolation of Benzoic Acid Esters and Acid-mediated Direct Cyclization
An efficient thioxanthone synthesis from benzoic acid esters is disclosed. Various thioxanthones were prepared by iridium-catalyzed C-H borylation of benzoic acid esters followed by copper-catalyzed deborylthiolation and direct acid-mediated cyclization. We also achieved a synthesis of benzo-fused thioxanthones through a transformation of an aryne intermediate having an ester moiety.