Aryl sulfone

Three forms of caustic soda are produced to meet customer needs purified diaphragm caustic (50% Rayon grade), 73% caustic, and anhydrous caustic. Regular 50% caustic from the diaphragm cell process is suitable for most appHcations and accounts for about 85% of the NaOH consumed in the United States. However, it caimot be used in operations such as the manufacture of rayon, the synthesis of alkyl aryl sulfonates, or the production of anhydrous caustic because of the presence of salt, sodium chlorate, and heavy metals. Membrane and mercury cell caustic, on the other hand, is of superior quaUty and... 

Emulsifiers. Removing the remover is just as important as removing the finish. For water rinse removers, a detergent that is compatible with the remover formula must be selected. Many organic solvents used in removers are not water soluble, so emulsifiers are often added (see Emulsions). Anionic types such as alkyl aryl sulfonates or tolyl fatty acid salts are used. In other appHcations, nonionic surfactants are preferred and hydrophilic—lipophilic balance is an important consideration. 

Others include tributyl phosphate [55612-35-6] alkyl aryl sulfonates, siUcones, and alcohols such as octanol [111-87-5]. 

The aromatic sulfone polymers are a group of high performance plastics, many of which have relatively closely related stmctures and similar properties (see Polymers containing sulfur, polysulfones). Chemically, all are polyethersulfones, ie, they have both aryl ether (ArOAr) and aryl sulfone (ArS02Ar) linkages in the polymer backbone. The simplest polyethersulfone (5) consists of aromatic rings linked alternately by ether and sulfone groups. 

G. Cla57ton and F. Cla57ton, eds., Patty s Industrial Hygiene andToxicology, 3rd ed., Vol. 2A, John Wdey Sons, Inc., New York, 1981, pp. 2089—2091. "Aryl Sulfonic Acids and Salts," Information Profiles on Potential Occupational Hayards, Vol. II, Chemical Classes, Center for Chemical Hazard Assessment, Syracuse Research Corp., U.S. Dept, of Commerce, Washington, D.C., 1979. 

All lation of Garbanions. Concentrated N a OH—hen syl triethyl amm onium chloride is the base/catalyst system normally used for this type of process (20). Classes of compounds alkylated in this way include phenylacetonitriles, ben2ylketones, simple aUphatic ketones, certain aldehydes, aryl sulfones, P-ketosulfones, P-ketoesters, malonic esters and nitriles, phenylacetic esters, indene, and fluorene (see Alkylation). 

Sulfates or sulfonates Alkali metal salts of sulfated alcohols, sulfonic acid salts alkyl-aryl sulfonates sodium laiiryl sulfate Nonaqiieoiis systems mixed aqueous and nonaqiieoiis systems oil-well drilling muds spent H3SO4 recovery deep-fat frying... 

An aryl methane- or toluenesulfonate ester is stable to reduction with lithium aluminum hydride, to the acidic conditions used for nitration of an aromatic ring (HN03/H0Ac), and to the high temperatures (200-250°) of an Ullmann reaction. Aryl sulfonate esters, formed by reaction of a phenol with a sulfonyl chloride in pyridine or aqueous sodium hydroxide, are cleaved by warming in aqueous sodium hydroxide. ... 

Heating of aryl halides or aryl sulfonates with alkali hydroxide,... 

As to arylisoxazoles, it was only in 1961 that Woodward et investigated the sulfonation of 5-phenylisoxazole. In contrast to nitration, only the phenyl nucleus is sulfonated to yield a mixture of m- and p-aryl sulfonic acid chlorides (62) in a 2 1 ratio. 

D. Arene Sulfonate-Aryl Sulfone (Sulfone-Fries) Rearrangement71... 

In principle, sulfonyl compounds bearing highly-electron-accepting substituents are able to transfer the sulfonyl group as an electrophile. Thus, the exchange of aryl substituents in methyl aryl sulfones under catalysis of trifluoromethanesulfonic acid takes place258 (equation 46). This reaction represents a further example for the reversibility of Friedel-Crafts reactions. 

Goering and coworkers201 studied the kinetics of base-promoted dehydrohalogenation of several series of cis- or frans-2-chlorocycloalkyl aryl sulfones. For the trans-2-chlorocyclohexyl series reacting with sodium hydroxide in 80% ethanol at 0 °C the p value was 1.42. The mechanism was considered to involve rate-determining carbanion formation, with the subsequent loss of chloride ion in a fast step. 

Alkylation of carbanions derived from allyl aryl sulfones 236 with alkyl halides is known... 

In the condensation reaction between chloro- and bromo-methyl aryl sulfones and carbonyl compounds, a-sulfonyloxiranes were obtained. In this condensation reaction, bases such as potassium t-butoxides372, NaH373 and aqueous concentrated hydroxide with benzyltriethylammonium chloride under two-phase condensation were used374. In the reaction with aldehydes only the trans-epoxide isomers resulted, whereas lith-iofluoromethyl phenyl sulfone 289375 and 291376 were found to add to aldehydes affording /J-hydroxysulfones 290 and 292, respectively. 

In 1950, Cope and coworkers48 unsuccessfully attempted to use the well-known Meisenheimer rearrangement of N-allylamine oxides to 0-allylhydroxylamines49 in performing the formally analogous rearrangements of allyl aryl sulfoxides to allyl arenesulfenates and of allyl aryl sulfones to allyl arenesulfinates (equations 11-13). 

C. The [2,3]Sigmatropic Rearrangement of Propargylic Arenesulfinates to Allenyl Aryl Sulfones... 

The central bond of the l-(arylsulfonyl)bicyclo[1.1.0]butane system behaves like the double bond of a, /i-unsaturated sulfones to give alkyl-substituted cyclobutyl aryl sulfones on treatment with organometallic reagents (equation 20)17. This method has been applied... 

TABLE 2. Yields of major radiolysis products from dialkyl/aryl sulfones (after Reference 70 with permission of the authors)0... 

The cleavage of alkyl aryl sulfones by sodium amalgam and alcohols65 probably proceeds also through the intermediacy of a radical anion, followed by splitting to the arylsulfinate anion and an alkyl radical. Both the sulfinate anion and the disproportionation products of the radical have been observed. 

Sulfones are thermally very stable compounds, diaryl derivatives being more stable than alkyl aryl sulfones which, in turn, are more stable than dialkyl sulfones allyl and benzyl substituents facilitate the homolysis by lowering the C—S bond dissociation energy17. Arylazo aryl sulfones, on heating in neutral or weakly basic media at 100°C, yield an aryl and arenesulfonyl radical pair via a reversible one-bond fission followed by dediazoni-ation of the aryldiazenyl radical (see Scheme 2 below)20. However, photolysis provides a relatively easy method for generating sulfonyl radicals from compounds containing the S02 moiety. 

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