Alkanesulphonic acids

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). 

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). 

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... 

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... 

Dissolve a sample containing 2-3 meq of mixed alkanesulphonic acids in water and dilute to 100 ml. 

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]. 

Alkyl alkanesulphonates react with Na naphthalene to form first the radical anion, which splits into R + O-SOa R , from which alkanols, alkanes, and alkanesulphinic acids are formed, depending on conditions. Photochemical cleavage of tosylated sterols and terpene alcohols at 254 nm proceeds in moderate yield within 3 h, in ether, to give back the alcohol via RSO2 + RO sulphonamides similarly give amines. ... 

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