Photoredox-Catalyzed Selective α-Scission of PR 3 -OH Radicals to Access Hydroalkylation of Alkenes.

Photoinduced generation of phosphoranyl radicals offers a versatile strategy to access a variety of synthetically valuable radicals. A long-standing challenge remains in the regulation of phosphoranyl radical to undergo α-scission pathway, although the β-scission mode has been intensively studied. We herein developed an unprecedented protocol for selective α-scission of the P(OH)R ₃ radical intermediate under photocatalytic conditions. This efficient P-C bond cleavage via α-scission of the P(OH)R ₃ radicals has been successfully utilized in the alkylation/fluoroalkylation of alkenes.