Reaction of diphenylchlorophosphine with 3,4-dichloro-5-hydroxy-2(5H)-furanone was used to prepare 3,5-dichloro-4-diphenylphosphinoyl-2(5H)-furanone. The reaction occurs involves nucleophilic substitution of the chlorine β to the carbonyl group and an unusual intermolecular rearrangement. The reaction with diethyl phosphorochloridite takes two routes: The first route is similar to that with diphenylchlorophosphine and the second involves the hydoxyl group
