Electron-Transfer Protocol for the Hydroxyalkenylation of Alkenes Using 1,2-Bis(phenylsulfonyl)ethylene

We report a protocol for alkene hydroxyalkenylation. Using a persulfate anion as a one-electron-oxidation reagent and 1,2-bis(phenylsulfonyl)ethylene as a radical acceptor in the presence of water, alkenes were converted into the corresponding 1-phenylsulfonyl-4-hydroxyalkenes in good to high yields. The hydroxyalkenylation process involves the nucleophilic hydroxylation of alkene radical cations to give beta-hydroxyalkyl radicals, which, after a radical addition/beta-elimination sequence, provide the products. We also report a photocatalytic protocol for alkoxyalkenylation. A simple protocol for alkene hydroxyalkenylation by 1,2-bis(phenylsulfonyl)ethylene was developed using persulfate anion as a one-electron oxidizing reagent. Regioselective hydroxyalkenylation was observed for a variety of substituted alkenes. A photocatalytic protocol for alkoxyalkenylation using an acridinium salt was also successful.image

Automated summary

This study reports a protocol for alkene hydroxyalkenylation and a photocatalytic protocol for alkoxyalkenylation. Alkenes can be converted into the corresponding 1-phenylsulfonyl-4-hydroxyalkenes or alkoxyalkenes in good to high yields using a persulfate anion as an oxidation reagent and 1,2-bis(phenylsulfonyl)ethylene as a radical acceptor. The methods exhibit wide substrate adaptability and regioselectivity.