Methyl sulfonates

Note 2. A large number of experimental examples are given in Ref. 108. In some cases methyl sulfonates can be successfully applied when the use of the sulfinic esters leads to mixtures of 1,1- and 1,3-substitution products. 

SuIfona.tlon, Sulfonation is a common reaction with dialkyl sulfates, either by slow decomposition on heating with the release of SO or by attack at the sulfur end of the O—S bond (63). Reaction products are usually the dimethyl ether, methanol, sulfonic acid, and methyl sulfonates, corresponding to both routes. Reactive aromatics are commonly those with higher reactivity to electrophilic substitution at temperatures > 100° C. Tn phenylamine, diphenylmethylamine, anisole, and diphenyl ether exhibit ring sulfonation at 150—160°C, 140°C, 155—160°C, and 180—190°C, respectively, but diphenyl ketone and benzyl methyl ether do not react up to 190°C. Diphenyl amine methylates and then sulfonates. Catalysis of sulfonation of anthraquinone by dimethyl sulfate occurs with thaHium(III) oxide or mercury(II) oxide at 170°C. Alkyl interchange also gives sulfation. 

Thiophene, 3,5-di-t-butyl-2-methyl-sulfonation, 4, 764 Thiophene, 2,4-dicarboxy-synthesis, 4, 870 Thiophene, 2,3-dichloro-synthesis, 4, 933 Thiophene, 2,5-dichloro-synthesis, 4, 933 Thiophene, 3,4-dichloro-... 

C8H10O2S, Benzyl methyl sulfone [(Methylsulfonyl)methyl]benzene ... 

The group contributions are given in Table 6. The group values were used to predict the enthalpy of formation of every compound in Tables 1-5 (except for those containing nitrogen). The estimated values were then compared to the experimental values. The agreement was usually to within about 10 kJ mol f The worst cases were for butyl methyl sulfone, t-butyl methyl sulfone and l-methyl-4-(l-methylethenylsulfonyl)benzene, for which the deviations were 12.4, 14.0 and 12.3 kJ mol-1, respectively. The average deviation was 4.4kJ mol-1. 

Recently, Co(III)-allyl complexes have been described to be sulfonylated regiospecifi-cally by sulfonyl halides under irradiation232 (equation 42). Similarly, allyl methyl sulfone has been obtained from allyltrimethylsilane under copper(I) catalysis213. 

Wegener and coworkers63 have reported the detailed investigation of a series of styryl methyl sulfones. 

Demeton-S-methyl sulfone (hRf 0-5), dimethoate (h/ f 5-10), demeton-S-metlq (hRf 20-25), triazophos (h/ f 40-45), azinphos-methyl (hRf 40-45), azinphos-ethj (hRf 50-55), malathion (h/ f 60-65), parathion-methyl (hRf 75-80) and parathioo ethyl (h/ f 80-85) yielded yellow to brown chromatogram zones on a light brown bact ground, with thiophosphate insecticides with P = S double bonds appearing as brow zones and those with single P — S bonds as yellow zones. 

Fig. 1 Reflectance scan of a chromatogram track with 100 ng each substance per chromatogram, one 1 = demeton-S-methyl sulfone, 2 = dimethoate, 3 = demeton-S-methyl, 4 = triazophos, 5 = azinphos-methyl, 6 = azinphos-ethyl, 7 = malathion, 8 = parathion-methyl and 9 = para-...

Further, tungsten oxysulfide films, WOyS, have shown promising behavior as positive electrodes in microbatteries, unlike WS2 that is not suitable as cathode in lithium cells. Using amorphous thin films of WO1.05S2 and WO1.35S2.2 in the cell Li/LiAsFe, 1 M ethyl-methyl sulfone (EMS)/W03,Sz, Martin-Litas et al. [80] obtained current densities up to 37 xA cm between 1.6 and 3 V. In these cathode materials, 0.6 and 0.8 lithium per formula unit, respectively, could be intercalated and de-intercalated reversibly. 

Bergman A, RJ Norstrom, K Haraguchi, H Kuroki, P Belaud (1994) PCB and DDE methyl sulfones in mammals from Canada and Sweden. Environ Toxicol Chem 13 121-128. 

Letcher RJ, RJ Norstrom, DCG Muir (1998) Biotransformation versus bioaccumulation sources of methyl sulfone PCB and 4,4 -DDE metabolites in polar bear food chain. Environ Sci Technol 32 1656-1661. 

As has been observed for other vinyl sulfones - , eclipsed forms prevail in the gaseous state of vinyl methyl sulfone, H2= H802 H3 , and a-bromovinyl methyl sulfone, H2= Br802 H3 The former appears as a mixture of two conformers in a 1 1 ratio... 

FIGURE 12. Two stable torsional forms of vinyl methyl sulfone. The projection formulas represent a view along the S—C(vinyl) bonds. 

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