Greening the Synthesis of 2,3‐Dihydrobenzofuran Selenides: I2/TBHP‐Promoted Selenocyclization of 2‐Allylphenols

In this work we describe the synthesis of selenium‐containing dihydrobenzofurans through the selenocyclization reaction of 2‐allylphenols. The reaction procedure uses only an I2/TBHP oxidant system at room temperature, enabling an efficient synthesis of 2‐[(organoselanyl)methyl]‐2,3‐dihydrobenzofurans. The products are formed immediately after the addition of the oxidant system in a mixture of 2‐allylphenol and diorganyl diselenide, in the absence of solvent, at mild experimental conditions. Furthermore, control experiments were carried out, including 77Se NMR analyses to identify intermediates, which contributed to the elucidation of the reaction mechanism.