Visible-light-promoted cascade selenylative cyclization of 2-alkynylthioa-nisoles for the synthesis of seleno-benzothiophenes

The photochemical cyclization of 2-alkynylthioanisoles with diselenides is demonstrated. Presented in this work is operationally simple, environmentally friendly and efficient, which enables a direct synthesis of selenobenzothiophenes under photocatalyst and metal-free conditions. The practicality and robustness of this cascade cyclization reaction are showcased by large-scale synthesis.