Sulfonyl Imides

Sulfonyl imides (78) are, like sulfenes, prepared by dehydrohalogenation of the corresponding sulfonyl chlorides (79) (usually called sulfamoyl chlorides). Like sulfenes, they take part in [2 + 2] and [4 + 2] cycloaddition reactions with electron-rich alkenes or with 1,3-dienes, yielding 1,2-thia-zetidine 1,1-dioxides (80)104 or dihydro-1,2-thiazines (81),105 respectively. 

These interesting compounds (82) are usually prepared by oxidation of sulfides with chloramine generated in situ from ammonia and tert-butyl 

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RTILs consist of large, unsymmetrical ions, such as 1,3-dialkyl-imidazolium, 1-alkylpyridinium, 1-alkylpyrazolium, tetralkylammonium or tetralkyl-phosphonium cations and tetrachloroaluminate, tetrafluoroborate, hexafluorophosphate, trifluoromethanesulfonate or bis((trifluoromethyl) sulfonyl)imide anions. 

Imidates are a different type of imine. Conceptually, imidates result from dehydration after condensation of a primary amido N-atom with the carbonyl of an ester function, although the actual synthetic route is often via an ortho ester (RC(OR )3). A large variety of A-sulfonyl imidates have been prepared and examined for their value as potential prodrugs containing a sulfonamide or an ester moiety [101][102], The hydrolysis of such compounds,... 

Fig. 11.9. Mechanisms and products of hydrolysis of aromatic N-sulfonyl imidates (11.66) as potential prodrugs of drugs containing sulfonamide or ester moieties [101] [102]...

The stability of these compounds is maximal at pH 4 - 6, and decreases very sharply at lower and higher pH values, and the mechanism and products of the reaction differed with pH. In the neutral range, hydrolysis yielded the aromatic sulfonamide and the ester, whereas, under acid catalysis in the low pH range, the products were the AT-acyl sulfonamide and an alcohol (R OH, Fig. 11.9). Of particular interest is that the tm values for hydrolysis of the N-sulfonyl imidates in 80% human plasma were 3-150 times lower than in buffer solution at identical pH and temperature. This was taken as evidence for enzymatic hydrolysis by human plasma hydrolases. Hydrolysis under these conditions yielded the sulfonamide and the ester in quantitative amounts. 

J. D. Larsen, H. Bundgaard, Prodrug Forms for the Sulfonamide Group. III. Chemical and Enzymatic Hydrolysis of Various V-Sulfonyl Imidates - A Novel Prodrug Form for a Sulfonamide Group or an Ester Function , hit. J. Pharm. 1989, 51, 2738. 

Savett, S. C., Atkins, J. R., Sides, G. R., Harris, J. L., Thomas, B. H., Greager, S. E., Pennington, W. T. and DesMarteau, D. D. 2002. A comparison of [(perfluoroalkyl) sulfonyl] imide ionomers and perfluorosulfonic acid ionics for applications in PEM fuel-cell technology. Journal of the Electrochemical Society 149 A1527-A1532. 

Figure 43. Structure of Nafion and bis[(perfluoroalkyl) sulfonyl] imide. ...

Verevkin, S.R et al.. Thermodynamic properties of mixtures containing ionic liquids. Vapor pressures and activity coefficients of n-alcohols and benzene in binary mixtures with l-methyl-3-butyl-imidazolium bis(trifluoromethyl-sulfonyl)imide. Fluid Phase Equilib., 236, 222, 2005. 

Baker and coworkers [16] reported on a self-referencing luminescent thermometer designed around the temperature-dependent intramolecular excimer formation/dissociation of the molecular probe l,3-Ws(l-pyrenyl)pro-pane (BPP) dissolved in 1-butyl-l-methylpyrrolidinium bjs(trifluoromethyl-sulfonyl)imide, [C4Cipyr][Tf2N]. Upon an increase in temperature, and hence a decrease in the IL s bulk viscosity, the excimer-to-monomer fluorescence... 

IS, 2R)-(+)-N,N-dimethylephedrinium fcis[(trifluoromethyl)sulfonyl]imide 6 [BeCiIm][TfO]... 

Ghen, R. Y., Hussey, G. L., Electrochemistry of ionophore-coordinated Cs and Sr ions in the tri-l-butylmethylammonium bis((trifluoromethyl)sulfonyl)imide ionic liquid, Electrochim. Acta, 50, 2533-2540, 2005. 

Lithium cyclodifluoromethane-l,l-bis(sulfonyl)imide 150 found an application as a conductive salt in nonaqueous electrolytes for lithium secondary batteries. The corresponding battery cells showed outstanding properties in respect to the capacity and the constant voltage <1997WO9731909>. 

It is possible to halogenate selectively at the methyl position of alkylpyridines to give halogenoalkylpyridines. Low to moderate yields of fluoromethylpyridines are obtained on fluorination of 2- and 4-methyl pyridines with (V-fluoro-bis[(trifluoromethyl)sulfonyl]imide 52 in the presence of sodium carbonate in dichloromethane <1996T15>. 2-Methylpyridine is fluorinated in 20% yield and 4-methylpyridine in 72% yield under these conditions. Reagent 52 also effects the selective fluorination of 2,4,6-collidine to give the 2-fluoromethylated product in moderate yield (Equation 35). 

Comparable results were obtained when an IL (ethyl-methylimmidazolium-bis(trifluoro-methane-sulfonyl)imide EMI-TFSI) was tested using a series of nanoporous carbons with average pore width in the range of 0.65-1.1 nm [18], The ion sizes, calculated as 0.79 and 0.76 nm in the longest dimension for TFSI and EMI ions, respectively, are within the range of carbons pore size. Figure 8.8 points out that, when the average pore size decreases from 1.1 to 0.7 nm, the normalized capacitance increases below 0.7 nm, the normalized capacitance decreases. Since the maximum at 0.7 nm is... 

Orthophosphinsaure-trihalogenide setzen sich mit Sulfonsaure- oder Carbonsaure-ami-den1093 nach Kirsanov1094zuPhosphinsaure-acyl(bzw. sulfonyl)imid-chloridenum ... 

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