Sulfuryl chloride reaction with carbohydrate derivatives

The first displacement reaction at C-2 position in carbohydrates was achieved during the study of sulfuryl chloride reaction with sucrose (92). Treatment of 3,4,6,3, 4, 6 -hexa-0-acetylsucrose 2,l -bis(chlorosulfate) with lithium chloride in hexamethylphosphoric triamide at 80°C for 20 h led to the corresponding 2,l -maimo derivative in 73% yield. 

B. Reaction of sulfuryl chloride with carbohydrate derivatives 111... 

In Section 11.8 a discussion of the reaction of sulfuryl chloride with carbohydrate derivatives is presented, and in Section III are given some experimental procedures representative of this method for the synthesis of chlorodeoxy sugars and procedures of simple processes for the conversion of the chlorodeoxy sugars into other rare sugars. 

B. Reaction of Sulfuryl Chloride with Carbohydrate Derivatives... 

The reaction of sulfuryl chloride with carbohydrate derivatives was investigated first by Helferich and co-workers [34-36J, and was extensively studied by Jones and his colleagues [37-45], The latter studies elucidated the stereochemical principles involved in the various transformations, and they have made available a convenient and effective procedure for the preparation of chlorodeoxy sugars. 

The reaction of sulfuryl chloride with carbohydrates to give chloro-deoxy derivatives has been reviewed briefly in this Series.98 The reaction of sulfuryl chloride with monosaccharides has been shown to afford products in which the secondary hydroxyl groups are replaced by chlorine with inversion of configuration.68-75 Jones and coworkers reported that the reaction of methyl a-D-glucopyranoside with sulfuryl chloride and pyridine in chloroform at room temperature proceeds by way of the 4,6-bis(chlorosulfate) by an Sn2 process, with chloride as the nucleophile, to give methyl 4,6-dichloro-4,6-dideoxy-a-D-galactopyranoside 2,3-bis(chlorosulfate).74... 

Cyclic sulfates can be prepared from cyclic but not acyclic carbohydrate units by reaction with sulfuryl chloride in pyridine [98] or phenyl chlorosulfate and sodium hydride [99]. The reactivity of cyclic sulfates is quite similar to that of epoxides. Thus, they can be used to form fluoro or azido derivatives of polysaccharides by highly regiospecific approaches, usually, but not always, leading to trans-diaxial products from which the sulfate can be easily removed by mild, acid-catalyzed hydrolysis [100,101]. 

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