Synthesis and reactivity of β-sulfonylvinylselenonium salts:: a simple stereoselective synthesis of β-functionalized (Z)-vinyl sulfones

The treatment of alkynylselenonium salt with benzenesulfinic acid in (PrOH)-Pr-i gives (Z)-beta -sulfonylvinylselenonium salts in good yields. The alkenylselenonium salts thus prepared react with nucleophiles such as alkoxides, halides, and acetylides to produce beta -functionalized (Z)-vinyl sulfones in high yields. Furthermore, we succeeded in the simple stereoselective one-step synthesis of various chiral (Z)-beta -alkoxyvinyl sulfones by the use of chiral alcohols.