The treatment of alkynylselenonium salt and various thiophenol derivatives with a catalytic amount of triethylamine gave beta-arylthioalkenylselenonium salts in good yields. The alkenylselenonium salts thus prepared reacted with nucleophiles such as acetylides, thiolates, and alkoxides to produce (Z)-beta-arylthio-alpha-functionalized ethenes in high yields. The vinylselenonium salts bearing a hydroxy