UVA Light‐promoted Catalyst‐free Cyclization of Vinyl Selenides: Green and Efficient Synthesis of C3‐Unsubstituted 2‐Selanyl Benzochalcogenophenes

Abstract

A metal-and catalyst-free photo-promoted cyclization of properly substituted vinyl selenides was developed using UVA irradiation. A total of eighteen new C3-unsubstituted 2-selanyl benzochalcogenophenes (benzofurans, benzothiophenes and benzoselenophenes) were prepared in 30-86% yield after irradiation with UVA at room temperature.The usefulness of the title compounds was demonstrated in the easy functionalization of the remaining free CÀ H bond of the benzochalcogenophenes to form new CÀ Se and CÀ Br bonds by simple procedures. Furthermore, the reaction can be performed under natural sunlight irradiation and the solvent is easily reused further in several subsequent runs.

A new method for creating Se–N intramolecular bonds using UV radiation

“…Organoselenium compounds comprise a wide variety of structures that are under continuous investigation in various research fields, including catalysis, 1 medicinal chemistry, 2 and materials science. 3 Isoselenazolones occupy a special place in this group of derivatives, with the well-known example of ebselen being a pioneered in the use of Se-compounds as therapeutics with antioxidant GPx-like potential.…”