Dichalcogenides/Oxone®‐Mediated Cyclization of (Z)‐Chalcogenoenynes under Ultrasound Irradiation

3‐Selanyl‐ and 3‐tellanylchalcogenophenes were prepared by the electrophilic cyclization of (Z)‐chalcogenoenynes under ultrasound irradiation conditions. This green procedure was carried out using Oxone® as an inexpensive and non‐toxic oxidant agent to promote the oxidative cleavage of Se−Se and Te−Te bonds. The electrophilic cyclization of (Z)‐1‐propylthio‐ and (Z)‐1‐butylselen‐1‐en‐3‐ynes was performed using the diaryl diselenide or ditelluride/Oxone®/ethanol system. The respective 3‐arylselanyl and 3‐aryltellanylthiophenes and selenophenes were obtained in 40 % to 87 % yield (16 examples). Similarly, 3‐arylselanyl and 3‐aryltellanyltellurophenes were synthesized by the cyclization of (Z)‐1‐butyltelluro‐1‐en‐3‐ynes, using glycerol as the solvent instead ethanol (5 examples; 28 % to 65 % yield). For the first time, Oxone® was used in the selective oxidative cleavage of the Te−Te bond in cyclization reactions. The system containing Oxone® as an oxidant under ultrasound irradiation conditions was used to access a series of 3‐chalcogenyl chalcogenophenes in short reaction time. This is a green and eco‐friendly protocol for the electrophilic cyclization of (Z)‐thio‐, (Z)‐seleno‐ and (Z)‐telluroenynes in the presence of diselenide or ditelluride/Oxone® system, furnishing 3‐functionalized thiophenes, selenophenes and tellurophenes, respectively, from 28 % to 87 % yield.