Methanesulfonic anhydride, sulfonylation

Methanesulfonic acid, sulfonylation of carbohydrates by, 239 Methanesulfonic anhydride, sulfonylation of carbohydrates by, 238 Methanesulfonyl chloride, sulfonylation agent for sugars, 236... 

Esterification Alumina. Boron trifluoride. Diazomethane. Dimethylformamide dimethyl acetal. Dimethylformamide dineopentyl acetal. Dimethyl sulfite. Diphenyidiazomethane. Ethyldicyclohexylamine. Ion-exchange resins. Isobutene. Methanesulfonic anhydride. 3 % Methanolic HCl (see Acetyl chloride). Methyl iodide. l-Methyl-3-p-tolyltriazine. Poly-phosphoric acid. Sulfosalicylic acid. Sulfuryl chloride. p-Toluenesulfonic acid. p-Tpluene-sulfonyl chloride. Triethylamine. Triethylorthoformate. Trifluoroacetic anhydride. Esterification of phosphoric acid Trichloroacetonitrile. 

Related Reagents. Acetic Anhydride Benzoyl Chloride Dimethyl Sulfoxide-Methanesulfonic Anhydride Methane-sulfonyl Chloride p-Toluenesulfonyl Chloride Trifluoroacetic Anhydride. 

Methanesulfonic and ben2enesulfonic anhydrides are the most frequently used anhydrides ia Friedel-Crafts sulfonylation reactions ... 

Other studies of selective sulfonylation at a primary hydroxyl group of sugars were made with 5-deoxy-l,2-0-isopropylidene-a-D-xy/o-hexofuranose at —12° to give the 6-p-toluenesulfonate and 6-methanesulfonate. On wanning the reaction mixture to 25°, these derivatives were converted into 3,6-anhydro-5-deoxy-l,2-0-isopropyl-idene-a-D-xyio-hexofuranose. The formation of 2,5-anhydrides on p-toluenesulfonylation of dialkyl dithioacetals of pentoses probably proceeds similarly, through the 5-p-toluenesulfonates. 

The desired sulfonate ester is usually prepared by reaction of the alcohol in pyridine with the appropriate sulfonyl chloride, that is, methanesulfonyl chloride (mesyl chloride) for a mesylate, y)-toluenesulfonyl chloride (tosyl chloride) for a tosylate, or trifluoromethane-sulfonyl chloride [or trifluoromethanesulfonic anhydride (triflic anhydride)] for a triflate. Pyridine (C5H5N, pyr) serves as the solvent and to neutralize the HCI formed. Ethanol, for example, reacts with methanesulfonyl chloride to form ethyl methanesulfonate and with yj-toluenesulfonyl chloride to form ethyl /-toluenesulfonate ... 

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