Carbohydrate Sulfones

Tipson s long-standing interest in sulfonic esters led him to contribute a landmark article on carbohydrate sulfonates for Volume 8 of Advances in Carbohydrate Chemistry, which marked the start of his editorial involvement with the series he joined as assistant editor to M. L. Wolfrom starting with Volume 9. This was the beginning of a long and fruitful association between Wolfrom and Tipson that assured researchers in the carbohydrate field of a regular series of authoritative articles on a wide range of topics, both fundamental and applied, related to carbohydrates. 

Hydrolysis can detoxify a wide range of aliphatic and aromatic organics such as esters, ethers, carbohydrates, sulfonic acids, halogen compounds, phosphates, and nitriles. It can be conducted in simple equipment (in batches in open tanks) or in more complicated equipment (continuous flow in large towers). However, a potential disadvantage is the possibility of forming undesirable reaction products. This possibility must be evaluated in bench- and pilot-scale tests before hydrolysis is implemented. 

The synthesis of desosamine hydrochloride served as the touch paper for much subsequent work in the area of nucleophilic displacement of carbohydrate sulfonic... 

SCHEME 42. The physical basis of Richardson s rules for nucleophilic displacement of carbohydrate sulfonic esters (1969). 

Until the introduction of triflate or imidazylate esters in carbohydrates, SN2-displacements of carbohydrate sulfonates with charged nucleophiles in certain positions of hexopyranose orfuranose derivatives were not possible, or gave low yields of substituted products owing to the predominance of elimination or rearrangement reactions [6,22,32,33]. 

Lithium aluminum hydride, effect of solvents on reduction of carbohydrate sulfonic esters, 269 Lutease, 380 Luteic acid, fungal, 378 Lyxitol, 1-acetamido-l-deoxy-L-, 170 Lyxofuranose, 5 - acetamido - 5 - deoxy-D-, 171... 

Platinum catalyst (Adams), in oxidation of carbohydrate sulfonic esters, 258 Poisson distribution, 304 Polarimetric measurement, of mutarota-tion, 47,52... 

Rotation, hindered, of acetyl group in monosaccharides, 193,197 Ruthenium tetraoxide, for oxidation of carbohydrate sulfonic esters, 258... 

Sinclair, H B, Displacement of carbohydrate sulfonates with halide ions of toluene-solubilized halides, Carbohydr. Res., 15, 147-153, 1970. 

It has been observed that the products from a given substrate and nucleophile are, in some cases, dependent on the solvent and the temperature, although no systematic studies have as yet been reported for carbohydrate sulfonates. This dependence is especially true when substitution and elimination mechanisms are both sterically feasible. Whereas a C-17 p-tolylsulfonyloxy group in the D-ring of a steroid underwent SN2 displacement with tetrabutylammonium chloride in boiling butanone, the same reactants in N-methyl-2-pynrolidinone at 160° gave 67% of the chloro derivative and 30% of the olefin.283 Participation by the inert solvents p-dioxane and acetone in sol-volyses of 2-octyl sulfonates was demonstrated by Weiner and Sneen,265 and this possibility must be considered when such solvents are used. The influence of environmental factors on rate and mechanism has been discussed by Banthorpe.288... 

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