PROCESS FOR REPARATION OF 3-HYDROXY- -BUTYROLACTONES

摘要

PURPOSE: A process for producing 3-hydroxy-γ-butyrolactones by halogenating chiral 3,4-epoxybutyric acid or its salt using water in place of an expensive solvent and cyclization without any special purification processes in one reactor is provided which produces 3-hydroxy-γ-butyrolactones in high yield and any low cost. CONSTITUTION: Chiral 3,4-epoxybutyric acid or its salt of formula 2 is halogenated and cycled in the presence of a water solvent to give 3-hydroxy-γ-butyrolactones of formula 1. In the halogenation, a halogenating agent alone or a mixture of the halogenating agent and acid are used in which the halogenating agent is halogen acid selected from chloric acid, bromic acid, or halogenated alkali metal salt selected from sodium chloride, sodium bromide, sodium iodide, potassium chloride and potassium bromide. In formula, a chiral center (*) represents (R)- or (S)-; M is hydrogen ion, metal ion or organic amine; X is a halogen atom.