Photochemical Benzylation of White Phosphorus

Organophosphorus compounds (OPCs) have wide application in organic synthesis, material sciences, and drug discovery. Generally, the vast majority of phosphorus atoms in OPCs are derived from white phosphorus (P₄). However, the large-scale preparation of OPCs mainly proceeds through the multistep and environmentally toxic chlorine route from P₄. Herein, we report the direct benzylation of P₄ promoted by visible light. The cheap and readily available benzyl bromide was used as a benzylation reagent, and tetrabenzylphosphonium bromide was directly synthesized from P₄. In addition, the metallaphotoredox catalysis strategy was applied to functionalize P₄ for the first time, which significantly improved the application range of the substituted benzyl bromide.