Alkanesulphonate salts

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 ... 

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 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). 

The sulphochlorination is a radical chain reaction, initiated by vis./UV light (A. < 480 nm, quantum yield of -2000). The reagents must contain O2 and H2O in very limited quantities. As a result, complex mixtures of isomeric alkanesulphonates are formed comprising di- and polysulphonates, paraffins, chloroparaffins and salts as well. Other stages allow for alkanesulphonate manufacturing of a sufficiently high quality. 

For better redox stability, Kim et al. [285] electrochemically synthesized the sodium salt of poly(n-anilino-l-alkanesulphonic acid) XVllI from modified aniline monomers. These polymers were evaluated for electrochromic reversibility by in situ spectroelectro-chemical and cyclic voltammetric techniques. High redox stability (>100000 scans) was observed in acetonitrile solution of 0.1 M NaC104 containing 5% (0.3 M) aqueous HC104. 

Sodhun salt of poly(n-anilino-l-alkanesulphonic acid), 853 Solar cells, 736... 

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