Straightforward glycosylation of various alcohols with unprotected and non-activated monosaccharides were performed under scandium triflate catalysis. Rate and yield of glycosylation were highly improved when using 1-butyl-3-methylimidazolium trifluoromethanesulfonate as a green solvent. This ionic liquid was allowed to be recycled at least three times without loss of activity. The possibility of drastically reducing the amounts of catalyst (down to 1 mol%) and aglycone (down to 1 equiv) when performing the reaction in ionic liquid opens new perspectives in O-glycosylation, as a direct coupling between an aglycone and free sugars.
在
钪三氟甲磺酸盐催化下,对各种醇与未保护和非活化的
单糖进行了直接的糖苷化反应。当使用1-丁基-3-甲基
咪唑三氟甲磺酸盐作为绿色溶剂时,糖苷化的反应速率和产率得到了显著提高。该
离子液体可至少回收使用三次而不会失去活性。在
离子液体中进行反应时,可以显著减少催化剂的用量(低至1 mol%)和糖苷的用量(低至1当量),这为O-糖苷化的直接耦合提供了新的前景,能够在糖苷和游离糖之间实现直接连接。