Reactions of Elemental Phosphorus and Phosphine with Electrophiles in Superbasic Systems: XVI. Phosphorylation of Benzyl Chloride with Elemental Phosphorus and Phosphine

The major product of the reaction of benzyl chloride with red phosphorus in the system concentrated aqueous KOH-dioxane-phase-transfer catalyst (43–95°C, Ar) is tribenzylphosphine oxide (yield up to 61%). Under similar conditions, phosphorylation of benzyl chloride with white phosphorus occurs differently, yielding dibenzylphosphine oxide as major product. Conditions are found for preparative synthesis of dibenzylphosphine from phosphine and benzyl chloride in the system KOH-DMSO.