Chlorodeoxy sugars chlorosulfate groups

The reaction of carbohydrates with sulfuryl chloride can form chlorosulfate groups initially, followed by Sn2 displacement of the liberated chloride ion. This provides another effective method for the preparation of chlorodeoxy sugars [34,53]. Those positions, where the steric and polar factors are favorable for a Sn2 reaction, are more susceptible to displacement. The chlorosulfates that have been substituted with a chloride can easily be cleaved by treatment with sodium iodide. 

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