Alkylsulfonylation

Chloroacetone, phenacylbromide, a-bromoisobutyrophenone, 3-bromo-3-methyl-2-butanone, 1 -alkylsulfonyl-3-bromo-2-propanone, and ethyl-y-chloroacetoacetate give with ammonium dithiocarbamate the corresponding 4-hydroxythiazolidine-2-thiones (177), which have a characteristic absorption between 273 and 279 nm. Dehydration by heating with dilute HCl can be followed by ultraviolet spectroscopy because the products formed (175) absorb at 315 to 340 nm. 

Pyrimidine, I-alkyl-2-methyltetrahydro-C-thioacylation, 4, 807 Pyrimidine, 4-alkylsulfinyl-nucleophilie displaeement reaetions, 3, 97 Pyrimidine, 6-alkylsulfinyl-nucleophilic displacement reactions, 3, 97 Pyrimidine, 2-alkylsulfonyl-nueleophilie displaeement reactions, 3, 97 Pyrimidine, 4-alkylsulfonyl-nucleophilic displacement reactions, 3, 97 Pyrimidine, 6-alkylsulfonyl-nucleophilie displaeement reactions, 3, 97 Pyrimidine, alkylthio-dealkylation, 3, 95 desulfurization, 3, 95 oxidation, 3, 96 synthesis, 3, 135, 136 Pyrimidine, 2-alkylthio-aminolysis, 3, 96 hydrolysis, 3, 95 Prineipal Synthesis, 3, 136 Pyrimidine, 4-alkylthio-aminolysis, 3, 96 hydrolysis, 3, 95 Pyrimidine, 6-alkylthio-aminolysis, 3, 96 hydrolysis, 3, 95 Pyrimidine, 4-allenyloxy-rearrangement, 3, 93 Pyrimidine, 4-allyloxy-2-phenyl-rearrangement, 3, 93 Pyrimidine, 4-allynyloxy-rearrangement, 3, 93 Pyrimidine, 4-anilino-2,5,6-trifluoro-NMR, 3, 63 Pyrimidine, 2-aryl-pyrroleaeetic aeid from, 4, 152 Pyrimidine, arylazo-synthesis, 3, 131 Pyrimidine, 4-arylazo-reduetion, 3, 88... 

Nucleophilic displacements of alkylsulfonyl groups in furazans (Scheme 184) have also been reported (96EUP776897). 

In a similar treatment of 3,4-bis(alkylsulfonyl)furoxans, both sulfonyl groups were eliminated (Scheme 191) (86H889). Bis(isoxazoline) 294 was isolated in 10-17% yield. 

These constitute the only category of substituted alkylsulfinyl and alkylsulfonyl groups for which there appears to be appreciable information. Compounds containing these groups have often been used in spectroscopic studies of inductive and resonance effects... 

Bis(alkylsulfonyl)methanes361,363 or bis(phenylsulfonyl)methane362 readily reacted with aldehydes in the presence of bases to afford /1-hydroxysulfones or bis-adducts. For example, bis(ethylsulfonyl)methane was found to react with salicylaldehyde in the presence of piperidine, affording 2-ethylsulfonylbenzofuran in a good yield363. 

J. Drabowicz, S. Legedz and M. Mikolajczyk, J. Chem. Soc., Chem. Commun., 1670 (1985) for preparation of alkanesulfinic acids from 2-(alkylsulfonyl)benzothiazoles, see Y. Ueno, A. Kojima and M. Okawara, Chem. Letters, 2125 (1984). 

In the second step the alkylsulfonyl chloride reacts with sulfuric acid ... 

When a general group (such as halo) is used, its priority is that of the lowest member of its group (see footnote 913). Thus the general name for this transformation is halo-alkylsulfonyl-addition because halo has the same priority as fluoro, its lowest member. 

Heesing and coworkers have reported the rearrangement of 0-alkylsulfinyl-iV-benzoyl-iV-phenylhydroxylamine (143) at — 70°C to the corresponding sulfonamide together with the o- and p-alkylsulfonyl derivatives 144 and 145 (equation 89). The reaction has been suggested to proceed by an intramolecular radical pair mechanism, as evidenced by experiments with oxygen-18 labeling and C-CIDNP effects. 

Alkylidene sulfenes (75), generally prepared by the dehydrohalogenation of alkylsulfonyl chlorides, add readily to electron-rich multiple bonds. For example, with enamines, the thietane dioxide (e.g., 76) is formed diazoalkanes yield thiirane dioxides (episulfones) and imines (Schiff bases) afford 1,2-thiazetidine 1,1-dioxides. There are available numerous reviews of sulfenes, including cycloaddition reactions.102... 

The ratio of the rate constants kp(2ktyyz can be calculated from experiments with different Vi and then the value of kp was estimated (for measurement of 2kt, see later). These experiments gave kp = 9.1 x 1012 exp(—62.0/RT) = 146 s-1 (300 K) [28]. The activation energy of this reaction seems to be close to the BDE of the C—S bond in the cyclohexylsulfonyl radical. The values of decay rate constants of various alkylsulfonyl radicals are listed in Table 12.1. 

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