48 / 2023-08-14 10:20:58

Photochemical Benzylation of White Phosphorus

White Phosphorus,Benzylation,Wittig reagent

New Technologies in Phosphorus Chemistry > 4) Inorganic phosphorus chemistry

White phosphorus (P₄) acts as a starting industrial material for the large-scale preparation of organophosphorus compounds (OPCs) via a classical P₄→PCl₃→OPCs route. From the economic and waste-disposal viewpoints, the direct functionalization of P₄ without chlorination to construct P−C bonds is of great significance.^[1] The traditional synthesis for benzyltriphenylphosphonium salts involves the chlorination of P₄, substitution by metal reagents and nucleophilic substitution of halogenated hydrocarbons.^[2] Herein, we report photochemical benzylation of P₄ to construct tetrabenzylphosphonium bromide directly. The tetrabenzylphosphonium salts can be used instead of the benzyltriphenylphosphonium salts in Wittig reaction, which was a commonly Wittig reagent for converting benzaldehyde to styrene derivatives.^[3]