Fluorosulfonic acid esters methyl fluorosulfonate

A mixture of fluorosulfonic acid and dimethyl sulfate distilled in glass -> methyl fluorosulfonate. Y > 80%. - Fluorosulfonic acid esters are excellent alkylating agents. F. e. and listing of good alkylating agents s. M. G. Ahmed et al., Chem. Commun. 1968, 1533. 

TOSMIC can be converted into an A-tosylmethylimidic ester or thioester (10) which will react with an aldimine to form a 1,2,5-trisubstituted imidazole (Scheme 4.2.3). These esters (10) can be made from A-tosylmethylacetamidc (from the Mannich condensation of p-toluenesulfonic acid, formaldehyde and acetamide [10]), which is smoothly converted by P4S10 in DME into the thioamide which forms the 5-methylated imidate when treated with methyl fluorosulfonate in dichloromethane. Yields of the Al-tosylmethylimidic thioesters are good (65-93%) they are fairly stable crystalline solids which are best stored under nitrogen at —20°C. In reaction with an aldimine in the presence of sodium hydride or potassium t-butoxide (in DME -DMSO or... 

The action of a Zn/Cu couple on 1,3-dibromo ketones and secondary amides yields 2-dialkylamino-1,3-dioxolanes (451 equation 208). Fluorosulfonic peracid anhydride adds to trifluoroacetonitrile to give an amide acetal (452 equation 209). In the addition of (Z)-2-butene-l,4-diol to trichloroacetoni-trile, catalyzed by sodium, the 1,3-dioxepin (453 equation 210) is produced. Bicyclic amide acetals (454 equation 211) are byproducts in the reaction of lactim ethers with diketene. TTie methyl esters of perfluorinated carboxylic acids react with diethanolamine to afford bicyclic amide acetals (455 equation 212). Heating of maleic anilides (456 equation 213) with acetic acid anhydride/sodium acetate gives heterocyclic compounds (457) containing an amide acetal structure. ... 

Cyclodehydration Aluminum chloride see also Methyl fluorene-9-carboxylate). Dowtherm. Fluorosulfonic acid. Hydrogen fluoride. Perchloric add. Phosphorus pentoxide. Phosphoryl chloride. Polyphosphate ester. Polyphosphoric add. Potassium bisulfate. Sodium aluminum chloride. Sulfur trioxide-Dimelhylformamide. />-Toluenesulfonic acid. Trifluoroacetic acid. Trifluoroacetic anhydride. 

Nucleophiles with two sites that could react with electrophiles are called ambident nucleophiles. The Hard and Soft Acids and Bases (HSAB) principle applies because a hard electrophile reacts at the harder nucleophilic site and a soft electrophile at the softer nucleophilic site. For instance, the sulfenate ion 70 is an ambident nucleophile, because it reacts (a) with methyl fluorosulfonate, a hard electrophile, at the oxygen atom, where most of the negative charge is concentrated, to give the sulfenate ester 71 and (b) with methyl iodide, a soft electrophile, to give the sulfoxide 72. Sulfur atom is the softer of the two nucleophilic sites available in the sulfenate ion and, furthermore, it is rendered more nucleophilic by the a-effect arising from the adjacent oxygen atom. 

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