A Novel Photoinduced Thioselenation of Allenes by Use of a Disulfide−Diselenide Binary System

Dependent on the selection of the lights employed, the relative reactivities of organic dichalcogenides toward carbon radicals, and the thermodynamical stability of products, it has become apparent that two different chalcogeno groups can be introduced simultaneously into allenes with excellent selectivity. The (PhS)2−(PhSe)2 binary system is effective for the regioselective thioselenation of allenes, affording β-selenoallylic sulfides in good yields. Further investigation on the reaction of allenes with (PhS)2 and (PhTe)2 afforded no thiotelluration products, unfortunately, due to the instability of C−Te bonds under photoirradiated conditions. However, a novel telluride-catalyzed dithiolation reaction of allenes with disulfides has been developed successfully, while the use of a disulfide single system could not effect the radical dithiolation of allenes

Highly Regioselective Thioselenation of Acetylenes by Using a (PhS)₂−(PhSe)₂ Binary System

Highly Regioselective Thioselenation of Acetylenes by Using a (PhS)2−(PhSe)2 Binary Syste

Highly Selective Thioselenation of Vinylcyclopropanes with a (PhS)₂−(PhSe)₂ Binary System and Its Application to Thiotelluration

A novel, highly selective method for introducing organic sulfur, selenium, and tellurium functions into vinylic cyclopropanes has been developed on the basis of the relative reactivities of organic dichalcogenides and chalcogen-centered radicals. Upon irradiation with the light of wavelength over 300 nm, the reaction of vinylcyclopropanes with diphenyl disulfide and diphenyl diselenide proceeds smoothly to provide the corresponding γ-(selenoethyl)allylic sulfides regioselectively in good yields. Similarly, vinylcyclopropanes undergo regioselective thiotelluration by use of a novel (PhS)2−(PhTe)2 binary system, affording the corresponding ring-opened thiotelluration product in good yields. Furthermore, the scope and limitations of this (PhS)2−(PhTe)2 binary system are discussed