A novel and practical synthesis of S-(1- and 2-halogenoalkyl)sugars by reaction of carbohydrate S-(O,O-dialkyl)phosphorodithioates and monothioates with fluoride anion

A useful synthesis has been developed of S-(1- and 2-halogenoalkyl)sugars in high yield and purity. Readily available sugar S-(O,O-dialkyl)phosphorodithioates undergo S-P bond rupture on reaction with fluoride ions to yield the corresponding sugar thiolates, which further react in situ with dichloromethane or 1,2-dihalogenoalkanes in the reaction medium. In this reaction, the halogenoalkanes play the role of both reactants and solvents.