Catalysis of Phosphorus(V)-Mediated Transformations: Dichlorination Reactions of Epoxides Under Appel Conditions

A stereospecific triphenylphosphine oxide-catalyzed 1,2-dichlorination reaction of epoxides has been developed. The reaction is effective for a range of terminal and internal epoxides In contrast to the classical Appel-type dichlorination of epoxides, oxalyl chloride is used as a stoichrometric reagent to generate the chlorophosphonium salt responsible for dichlorination from catalytic triphenylphosphine oxide.