Free-radical addition of phosphine to vinyl ethers: atom-economic synthesis of tris(2-organyloxyethyl)phosphines and their derivatives

Phosphine, generated from red phosphorus in the system KOH–H₂O–toluene, reacts with vinyl ethers under radical initiation (AIBN, dioxane, 78–80°C, atmospheric pressure) to give tris(2-organyloxyethyl)phosphines, which are transformed to the corresponding phosphine chalcogenides (in up to 73% isolated yield) via the reactions with air oxygen, elemental sulfur or selenium.