An efficient approach for the synthesis of oligosaccharides using ionic liquid supported glycosylation

The synthesis of complex oligosaccharides has been a challenge due to their multifarious protections, deprotection processes and time-consuming chromatography. Herein, an effective strategy for the establishment of a library of oligosaccharides using imidazolium-type cation as a soluble functional support with ester and ether as linkage was demonstrated and developed. Noteworthy, IL-linkages have defined structures and molecular weights in contrast to polymer linkages, which are functionalized materials with variable loading capabilities allowing the efficient homogenous reaction conditions. All IL-tagged intermediates can be clipped off and purified by a simple phase-separation technique without further column chromatography after each glycosylation step.