Photoredox Hydroxy-arylation of the Terminal Double Bond of N -Substituted 3-Methyleneisoindolin-1-ones in Visible Light.

Mild and efficient ruthenium-catalyzed hydroxy-arylation of the terminal double bond of N -substituted 3-methyleneisoindolin-1-ones is described. The reaction takes place with aryl diazonium salt as the arylating reagent and water as the hydroxyl source in visible light at ambient temperature. The strategy entails vicinal difunctionalization of alkene and enables construction of 3-benzyl-3-hydroxyisoindolin-1-one heterocyclic scaffolds in moderate to good yields. C-C and C-O bonds are formed in one pot without any external additive and oxidant through an in situ generation of a carbocation intermediate in green light.