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.