Aryl sulfonic acids

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. 

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. 

Cationic polymerization of cyclosiloxanes is well known but used much less frequently than anionic reactions. The most widely used catalysts include sulfuric acid and its derivatives, alkyl and aryl sulfonic acids and trifluoroacetic acid1 2,1221. Due to their ease of removal, in industrial applications acid catalysts are generally employed on supports such as bentonite clay or Fuller s earth. 

Diaryl sulfones can be formed by treatment of aromatic compounds with aryl sulfonyl chlorides and a Friedel-Crafts catalyst. This reaction is analogous to Friedel-Crafts acylation with carboxylic acid halides (11-14). In a better procedure, the aromatic compound is treated with an aryl sulfonic acid and P2O5 in polypho-sphoric acid. Still another method uses an arylsulfonic trifluoromethanesulfonic anhydride (ArS020S02CF3) (generated in situ from ArS02Br and CF3S03Ag) without a catalyst. ... 

Ammonium salts of alkenyl succinic half-amides have teen described for use as corrosion inhibitors in oil and gas production technology to combat corrosion by media containing CO2, H2S, and elemental sulfur [1366]. The inhibitor composition may contain a dispersing agent, such as a low molecular weight or polymeric anionic surfactant like an alkylsulfonic acid or an alkyl-aryl sulfonic acid. 

Vogel, C., Meier-Haack, J., Taeger, A. and Lehmann, D. 2004. On the stability of selected monomeric and polymeric aryl sulfonic acids on heating in water (part 1). Fuel Cells 4 320-327. 

A heteroaromatic nucleus can serve also as an acceptor for the migrating sulfonyl group. Thus, irradiation of numerous 4-pyrimidinyl esters of alkyl and aryl sulfonic acids (24) in alcohol with low-pressure mercury arcs readily... 

Aryl chloride Aryl iodide Aryl selenic acid Aryl sulfonic acid Azide... 

Polysulfonates can also be obtained using the condensation reaction of aryl sulfonic acids with arenes [Eq. (45)] [134],... 

Sulfonation of aromatic compounds is very important in the manufacture of dyes. As sulfonic acids are generally water-soluble, the sulfonation of aromatic compounds provides a means to make aromatic compounds water-soluble. Also, the sulfonic acid group is easily displaced by a variety of other groups. Therefore, aryl-sulfonic acids are useful synthetic intermediates. 

The first reagent in example (b) looks like a reagent in example (a) but, in fact, it is not incorporated into the product and must be a catalyst. It is an aryl sulfonic acid and will be a strong acid. The product contains two t-butyl groups and can be formed only by an Sn 1 mechanism. 

The preferred eluents for anions are dilute carbonate-bicarbonate mixture, sodium hydroxide and, for common alkali metals and simple amines, dilute mineral acids (HCl, HNO3, BaCb, AgN03, amino acids, alkyl and aryl sulfonic acids). The most common... 

Cation Exchange Extractants. This class of extractants includes phenols, branched alkyl carboxylic acids, alkyl phosphoric acids, diketones, and alkyl-aryl sulfonic acids. The last group listed, sulfonic acids, are analogous to sulfonic-acid cation exchange resins and have very little selectivity. Diketones, alkyl phosphoric acids and carboxylic acids can provide both cation exchange functions and coordination functions. This feature has made bis(2-ethylhexyl)phosphoric acid one of the most versatile and powerful extractants of this type. (5) The nation below illustrates simple cation exchange extraction. 

Stein et al. (1944) have made use of their method of specific precipitation with aryl sulfonic acids to isolate peptides from an acid hydrolyzate of silk fibroin. Gly.Ala was isolated in 5.5% yield using 2 5-dibromo-benzene sulfonic acid and Ala.Gly in 6.0% yield using 2,6-diiodophenol-4-sulfonic acid. 

The sulfonation of aromatic compounds occurs readily in ionic liquids, with the simplest case being the direct sulfonation of aromatic compounds with sulfur trioxide to give the aryl sulfonic acid [113]. Ionic liquids such as triflate or triflimide ionic liquids were found to enhance the reaction rate. In the reaction of chloro-sulfuric acid with aromatic compounds, the reaction in the ionic liquid gave a... 

Mesoporous silicas modified with acidic groups [e.g. grafted alkyl or aryl sulfonic acids, or containing heteropolyacids or sulfated zirconia within their large pores) have generally provided higher yields, with several systems achieving over 70% yield. Amberlyst resins have been used in these reaction with some success, and the best systems (75% and 100% yield) both required DMSO as solvent, attributed to its ability to remove water and minimise decomposition reactions of the products. ... 

The Institute of Natural Fibres in Poznan, Poland has developed new barrier fabrics, both woven and non-woven. The first was a cotton weave containing a small addition of polyester. The latter was made of flame retardant flax and hemp fibres. The flame retardant and its application method were developed by the institute. The flame retardant, called FOBOS M2T, was based on urea polyborates and the sodium salt of alkyl-aryl sulfonic acid. The method of impregnation is cheap and simple. It can be carried out on typical finishing equipment and increase manufacturing costs by only 10-15%. 

However, one aromatic sulfonic acid is rather important. Sulfonic acid 83 has the common name para-toluenesulfonic acid (tosic acid), and it is commonly used as an acid catalyst because it is reasonably soluble on organic solvents. Tosic acid has been used several times in previous chapters, including Chapter 10 (Sections 10.3 and 10.6) and Chapter 11 (Section 11.4). Chapter 21 will describe the formal nomenclature of aryl sulfonic acids, but the lUPAC name of 81 is benzenesulfonic acid and 83 is 4-methylbenzenesulfonic acid. However, the common name is used most often for 83. 

Table 23-5 Barium pigments listed in EINECS in sub group "l-azo-2-hydroxynaphthalenyl aryl sulfonic acid, barium salts .

---