Efficient Synthesis of 2,4-Bis(phenyl)-1,3-diselenadiphosphetane-2,4-diselenide (Woollins' Reagent).

An improved approach for the preparation of 2,4-bis(phenyl)-1,3-diselena-2,4-diphosphetane-2,4-diselenide (Woollins' reagent) is described. Reacting dichlorophenylphosphine with Na2Se which was in situ prepared from the reaction of elemental selenium and metal sodium in the presence of naphthalene in refluxing tetrahydrofuran generated Woollins' reagent with excellent purity and a yield of up to 96.4%.