Application of Halide Molten Salts as Novel Reaction Media for <i>O</i>‐Glycosidic Bond Formation

Abstract

Abstract In this study we have explored the application of halide molten salts as reaction media for O ‐glycosidic bond formation under basic conditions and mild heating. Eighteen different room‐temperature ionic liquids and molten salts, representing four different classes of cations (i.e. imidazolium, pyridinium, pyrrolidinium and ammonium), were screened in the glycosidation reaction of p ‐nitrophenol with acetobromo‐α‐ D ‐galactose. 1‐Butyl‐4‐methylimidazolium chloride (BMIM · Cl) gave the best results and was applied in the reactions of other phenolic substrates to give the products with up to 80 % yields. All the reactions were highly selective to give the β‐anomers, and the molten salt BMIM · Cl couldeasily be reused with no apparent loss in activity.