Synthesis of 3‐Chalcogenyl‐benzo[ b ]Chalcogenophenes via Chalcogenation/Cyclization of Alkynes Promoted by Selectfluor
Jean C. Kazmierczak, Kelvin V. Hübner, Eduarda R. Fritz, Paola S. Hellwig, Claudio C. Silveira, Ricardo F. SchumacherABSTRACT
A straightforward and efficient strategy for the synthesis of 3‐selanyl‐benzo[ b ]thiophenes is reported via the electrophilic cyclization of 2‐alkynylthioanisoles. This operationally simple reaction is conducted using Selecfluor as a mild, stable, and easy‐to‐handle oxidizing agent. The methodology is compatible with various functional groups, affording a range of benzo[ b ]thiophenes through the formation of new C─S and C─Se bonds in a single step, with moderate to good yields. Furthermore, the tolerance to disulfides and ditellurides demonstrates the flexibility of this new methodology in incorporating multifunctionalities into the synthesized benzochalcogenophenes.