Liliane S de Farias, Sabrina B Acosta, Luiz H Dapper, Bruna R Schneider, Angelita M Barcellos, Liane K Soares, Adriano B de Oliveira, Diego Alves, Alex F C Flores, Gabriel P da Costa
An efficient FeCl3-mediated intramolecular cyclization of o-alkynyl diaryl ethers with diorganyl diselenides has been developed, providing selenylated dibenzo-[b,f]-oxepines in good to excellent yields under mild conditions. The optimized protocol using 0.6 equiv of diorganyl diselenide and 1 equiv of FeCl3 in DCM at room temperature exhibited a broad substrate scope and high tolerance toward diverse functional groups. This approach occurs by in situ formation of an electrophilic selenium species, which undergoes a 7-endo-dig cyclization to furnish the heterocyclic core. This method provides straightforward access to functionalized dibenzo-[b,f]-oxepines containing selenium, a motif of interest due to its relevance in medicinal chemistry and materials science.