10.1039/b718642h
The research focuses on the development of a novel purification strategy for iodine(III)-promoted glycosidations of 2-deoxy diethyldithiophosphate glycosides using a tagged iodine(III)-promoter. The purpose of this study was to address the challenges associated with the removal of by-products, such as iodobenzene, which are common in hypervalent iodine chemistry and can be cumbersome to remove chromatographically. The researchers introduced a concept based on a sulfonate ester tag that acts as a dormant ion exchange group, allowing for the liberation and removal of the sulfonate anion via an SN2-step and subsequent anion exchange resin capture. The tagged iodine(III) reagents were prepared from commercially available p-iodo-benzenesulfonyl chloride (pipsyl chloride) and were used to activate glycosyl donors in the presence of various glycosyl acceptors. The study concluded that this method, combined with a scavenging protocol, is a powerful glycosidation approach for diethyldithiophosphates and has general applicability for purification protocols of reagents and catalysts. Key chemicals used in the process include p-iodo-benzenesulfonyl chloride, i-butyl sulfonate, bis(acetoxy)iodoarene, iodosylbenzene, and the Zefirov reagent, as well as various glycosyl donors and acceptors such as diethyldithiophosphates and decarestrictines.