Sulfonyl Components

the iminoester (9) reacts with carbazate (8) to give 10, which cyclizes under basic conditions to the triazolinones (11). 

The methylation of 14, prepared via imidoester 13 [36], takes place exclusively at the amidic nitrogen. 

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The sulfonyl component of propoxycarbazone-sodium (2) is an integral part of several commercial sulfonylureas [21]. Technical procedures exist for sulfonyl isocyanate preparation starting from saccharin (Scheme 2.6.5) [22, 23]. 

During optimization of the sulfonyl component it was found that the sulfonylaryl moiety is more potent than the corresponding sulfonylmethylaryl structure. However, particularly good activity and cereal selectivity were identified for the halogenated substitution pattern in the ortho-position of the latter, such as tri-fluoromethyl and trifiuoromethoxy. 

Reactivity ratios for the copolymerization of AN with 7 in methanol at 60 °C, proved to be equal to rx AN= 3,6 0,2 and r%n = 0 0,06, i.e., AN is a much more active component in this binary system. The low reactivity of the vinyl double bond in 7 is explained by the specific effect of the sulfonyl group on its polarity26. In addition to that, the radical formed from 7 does not seem to be stabilized by the sulfonyl group and readily takes part in the chain transfer reaction and chain termination. As a result of this, the rate of copolymerization reaction and the molecular mass of the copolymers decrease with increasing content of 7 in the initial mixture. 

Two-component methods represent the most widely applied principles in sulfone syntheses, including C—S bond formation between carbon and RSOz species of nucleophilic, radical or electrophilic character as well as oxidations of thioethers or sulfoxides, and cheletropic reactions of sulfur dioxide. Three-component methods use sulfur dioxide as a binding link in order to connect two carbons by a radical or polar route, or use sulfur trioxide as an electrophilic condensation agent to combine two hydrocarbon moieties by a sulfonyl bridge with elimination of water. 

Microwave and fluorous technologies have been combined in the solution phase parallel synthesis of 3-aminoimidazo[l,2-a]pyridines and -pyrazines [63]. The three-component condensation of a perfluorooctane-sulfonyl (Rfs = CgFiy) substituted benzaldehyde by microwave irradiation in a single-mode instrument at 150 °C for 10 min in CH2CI2 - MeOH in the presence of Sc(OTf)3 gave the imidazo-annulated heterocycles that could be purified by fluorous solid phase extraction (Scheme 9). Subsequent Pd-catalyzed cross-coupling reactions of the fluorous sulfonates with arylboronic acids or thiols gave biaryls or aryl sulfides, respectively, albeit it in relatively low yields. 

Toluene-p-sulfonyl azide adds to electron-deficient acetylenes and to phenylacetylene at 80°-100° over a period of several days. The azide adds much more readily to ynamines, - refiecting the electronic compatibility of these components. The triazoles so formed are labile and exist in equilibrium with open-chain diazo tautomers (Section IV, G) the adduct with ethoxyacetylene exists entirely in the diazo form. Other sulfonyl azides have been reacted with arylacetylenes, but yields of triazoles are generally poor. ... 

The combinatorial reactions chosen for the novel amines were amide bond formation and sulfonamide formation. The novel carboxylic acids were derivatized to simple amides. For the amine reactions, we chose two simple carboxylic acids (propionic acid and benzoic acid) and two simple sulfonyl chlorides (methyl-sulfonyl chloride and benzenesulfonyl chloride) as the capping groups. Propyl amine and benzylamine were chosen as the capping groups to react with the novel carboxylic acids. Because only one reactant will be variable, these combinatorial libraries were essentially 1 x N libraries, where the one reactant was a simple reactant and the N component is the novel amines or acids. 

These two components of the ESR spectrum may be attributed to an alkyl radical and a sulfonyl radical. The presence of two radicals can be confirmed by power saturation experiments. The spectrum at high microwave power shows increased intensities for the lines due to the alkyl radical and... 

Sulfasalazine. Salicylazosulfapyridine or Azulfadine [599-79-1] (2-hydroxy-5-[[4[(2-pyridylamino)sulfonyl]-phenyl]azo] benzoic acid) (15) is a light brownish yellow-to-bright yellow fine powder that is practically tasteless and odorless. It melts at ca 255°C with decomposition, is very slightly soluble in ethanol, is practically insoluble in water, diethyl ether, chloroform, and benzene, and is soluble in aqueous solutions of alkali hydroxides. Sulfasalazine may be made by the synthesis described in Reference 13. It is not used as an antidiarrheal as such, but is indicated for the treatment of inflammatory bowel diseases such as ulcerative colitis and Crohn s disease. Its action is purported to result from the breakdown in the colon to 5-aminosalicylic acid [89-57-6] (5-AS A) and sulfapyridine [144-83-2]. It may cause infertility in males, as well as producing idiosyncratic reactions in some patients these reactions have been attributed to the sulfa component of the compound. The mechanism of 5-ASA is attributed to inhibition of the arachidonic acid cascade preventing leukotriene B4 production and the ability to scavenge oxygen free radicals. The active component appears to be 5-aminosalicylic acid. 

A remarkable stereospecific dehydrative alkylation of (3-disulfones was reported by Falck et al. [406] under Mitsunobu conditions (triethyl phosphine, diethyl azodicarboxylate). The synthesis of a pheromone component of the lesser tea tortrix emphasizes some of the possibilities offered by coupling this reaction with further uses of the sulfone functionality. In the present case, monodesulfonylation with lithium naphthalenide (-78°C, 5 min), in situ alkylation (-78 to 23°C, 1 h), and Li-naphthalene cleavage of the second sulfonyl group (—78°C, 5 min) yielded in a one-pot procedure a THP ether which was converted into the sought after pheromone through direct acetylation. 

Buffer catalysis of the hydrolysis of phenyl (311 R = Ph) and methyl (311 R = Me) benzenesulfinates to give the sulfinic acid (312) and alcohol ROH is strongly accelerated by both carboxylate and amine components of the buffer which give Bronsted /i values of approximately unity on separate lines. The carboxylates are about 44 tunes more effective than amines of similar basicity. A concerted. S n2 mechanism with a hypervalent intermediate (313) is proposed for the nucleophilic reaction of these esters.286 The reaction of the thiosulfinate esters (314) with sulfenyl chlorides RSCI and sulfenate esters (315) to give sulfinyl chlorides and disulfides and sulfinate esters and disulfides, respectively, has been studied.287 Hydrolysis of 2-(3-aminophenyl)sulfonyl-ethanol hydrogensulfate gives under different conditions various products such as the ether (316) and the sulfone (317).288... 

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