Alkanesulphonates

An early method developed for the assay of detergents based upon the sodium salts of the higher homologues of the alkanesulphonic acids,21 involved treatment of an aqueous solution of the detergent with methylene blue in the presence of chloroform. Reaction takes place between the ionic dyestuff (which is a chloride) and the detergent ... 

Oxidation of methyl perfluoroalkyl sulphones with refluxing aqueous potassium permanganate produced the perfluorinated alkanesulphonic acid in 85% yield as the potassium salt (equation 86). On the other hand, attempted oxidation with sodium hypochlorite caused only chlorine substitution (equation 87). Reaction of the new sulphone with aqueous hydroxide gave the same perfluoroalkane sulphonic acid salt (equation 88). 

Reduction of conjugated carbonyl compounds using stoichiometric amounts of the ammonium salt shows little advantage over the sodium salt in acidic methanol [11] with both reagents producing allylic alcohols (58-88% for acyclic compounds and 15-64% for cyclic compounds) by selective 1,2-reduction of the conjugated systems. Aldehydes, ketones and conjugated enones are also reduced by tetra-n-butylammonium cyanoborohydride in HMPA [11, 12], whereas haloalkanes and alkanesulphonic esters are cleaved reductively under similar conditions [13]. 

The halogenation of alkanes in the presence of sulphur dioxide yields alkanesulphonyl chlorides (5.79), and these are made in large quantities for conversion to metal alkanesulphonates (used as emulsifiers in polymerizations) or to nitrogen-containing derivatives. The sulphur dioxide acts by trapping the alkyl radical it does not terminate the chain mechanism, and so quantum yields can be very high (—2000). 

Dish Washing Agent clear, liquid, 25% WAS alkanesulphonate ethersulphate=4.1... 

Canselier, J.P. (2004) A new process for the manufacture of alkanesulphonates. Proceedings 6th World Surfactants Congress. 

Direct addition of an alkylsulphonate into imidazole is useful, not only to synthesize the sulphonate anion, but also different anions via metathesis in the halogen free method. For example, the alkylation of /V-alkylimida/oles such as /V-mcthylimidazolc with alkylsulphonate can be performed under solventless conditions at room temperature affording, after 48-72 h, the corresponding 1,3-dialkylimidazolium alkanesulphonate salts as crystalline solids in almost quantitative yields (5) [48], The alkane sulphonate anions can easily be substituted by a series of other anions by metathesis ... 

The resulting polymer was isolated in the form of the sodium salt, as a white powdery substance corresponding to the above composition. Absorption bands at 1200 1210 cm typical for r asym (SO2) in alkanesulphonic acids were found in the IR spectra. An absorption band at 1070 cm seems to correspond to both stretching vibrations of a Si-O-Si bond and r sym(S02). 

Roberts, D.W., fraginals, R., Lepoittevin, J.-P. and Benezra, C. (1991) Refinement of the relative alkylation index (RAI) model for skin sensitization and application to mouse and guinea-pig test data for alkyl alkanesulphonates. Archives of Dermatological Research, 283, 387—394. 

Tarlov and coworkers studied the mechanism of photo-oxidation of the alkanethiol monolayers on the silver surface and found that UV irradiation leads first to the scission of the C—S bond and removal of the alkane portion of the monolayer. Remaining sulphur species are then oxidized to produce sulphite and sulphate ions289. As alkanesulphonate peaks were, however, observed in the aged alkanethiol monolayers on the Au(lll) surface (vide supra), the generality of this mechanism is unclear. 

Empirical equations have been developed for the 13C chemical shifts of alkanesulphonic acids, and the substituent effects of S03- on alkane chemical shifts, relative to H, have been calculated58 to be a-C, 39.7 /2-C, 3.7 and y-C, — 0.2 to — 2.1 ppm. These effects are quite small in relation to the electron-withdrawing effect the N02 group deshields an a-carbon nucleus by 64 ppm59. 

TABLE 13. 13C NMR chemical shifts of some alkanesulphonic acids and their sodium salts57... 

Metallation of alkanesulphonate esters of alcohols which have been functionalized at the 2- or 3-positions leads to y- and <5-sultones often in good yield. In this way <5-sultone 12 was prepared from propane-1,3-dimethylsulphonate (equation 24) by Durst and Tin49. 

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