Sulfonic acid esters benzenesulfonic

Oae found that for both base- and acid-catalyzed hydrolysis of phenyl benzenesul-fonate, there was no incorporation of 0 from solvent into the sulfonate ester after partial hydrolysis. This was interpreted as ruling out a stepwise mechanism, but in fact it could be stepwise with slow pseudorotation. In fact this nonexchange can be explained by Westheimer s rules for pseudorotation, assuming the same rules apply to pentacoordinate sulfur. For the acid-catalyzed reaction, the likely intermediate would be 8 for which pseudorotation would be disfavored because it would put a carbon at an apical position. Further protonation to the cationic intermediate is unlikely even in lOM HCl (the medium for Oae s experiments) because of the high acidity of this species a Branch and Calvin calculation (See Appendix), supplemented by allowance for the effect of the phenyl groups (taken as the difference in between sulfuric acid and benzenesulfonic acid ), leads to a pA, of -7 for the first pisTa of this cation about -2 for the second p/sTa. and about 3 for the third Thus, protonation by aqueous HCl to give the neutral intermediate is likely but further protonation to give cation 9 would be very unlikely. 

Esters of sulfonic acids can rearrange photochemically to give sulfones in moderate yields [147], Thus, phenyl benzenesulfonate (182) cleaves photochemically producing 15% of ort/to-hydroxyphenyl phenyl sulfone (183) and 31.1% of para-hydroxyphenyl phenyl sulfone (184). Besides, 17.4% of phenol (13) is formed... 

Esters of aliphatic and aromatic sulfonic acids are conveniently prepared in high yields from alcohols and sulfonyl halides. A basic medium is required. By substituting sodium butoxide for sodium hydroxide in butanol, the yield of n-butyl p-toluenesulfonate is increased from 54% to 98%. Ethyl benzenesulfonate and nuclear-substituted derivatives carrying bromo, methoxyl, and nirro groups are prepared from the corresponding sulfonyl chlorides by treatment with sodium ethoxide in absolute ethanol the yields are 74-81%. Pyridine is by far the most popular basic medium for this reaction. Alcohols (C -Cjj) react at 0-10° in 80-90% yields, and various phenols can be converted to aryl sulfonates in this base. "... 

Benzenesulfonamide, Ar,AT-dibromo-4-methyl-(TsNBr2) bromohydrination with, 287 Benzenesulfonamides reductive cleavage, 247 synthesis of drugs, 301, 307-308 Benzenesulfonic acids. See Sulfonic acids Benzenesulfonic acid, 4-methyl-, esters (tosylates) alkyl a-synthons, 16, 24, 47, 93 fragmentation of, 89 rearrangement of, 32 reductive cleavage of, 114, 202-203 —, 4-methyl-, hydrazide (tosylhydrazine) hydrazones of fragmentation, 89 reduction, 109... 

In Figure 11.2, a sulfonate ester is the leaving group, and reaction with a nucleophile breaks the weaker C-0 bond to generate a sulfonate anion (26). This anion is resonance stabilized and quite stable, which means it is relatively unreactive as a nucleophile. The combination of a weak C-0 bond and the stability and poor reactivity of the sulfonate anion makes sulfonate esters good leaving groups. The most common sulfonate esters (see Chapter 20, Section 20.11) are those derived from methanesulfonic acid, benzenesulfonic acid, or 4-methylbenzenesulfonic acid. Formation of sulfonate esters from sulfonic acids or sulfonyl chlorides will be discussed in Section 11.7.3 and in Chapter 20,... 

The sulfonate esters decompose in aqueous solutions to the corresponding sulfonic acids and alcohols. The rate of decomposition of the sulfonate esters of primary alcohols depends on the stability of the sulfonate ion formed upon hydrolysis. For example, in sodium phosphate at pH 7.9 and 25°, ethyl 2-benzothiazolesulfonate (Ha) and methyl 4-nitro-benzenesulfonate (I) have half-lives of about 12 and 60 min, respectively. Isopropyl 2-benzothiazolesulfonate (Ilb) proved to be very reactive to... 

Sulfonic acids and sulfonate salts contain the -SO3H and -SO3 groups, respectively, attached to a hydrocarbon moiety. The structural formula of benzenesulfonic acids and of sodium 4-decylbenzenesulfonate, a biodegradable detergent surfactant, are shown in Figure 9.13. The common sulfonic acids are water-soluble strong acids that lose virtually all ionizable in aqueous solution. They are used commercially to hydrolyze fat and oil esters to fatty acids and glycerol. 

Sultones are the internal esters of hydroxy sulfonic acids and sulfur analogs of lactones. The biological activities of sultones are concerned with toxicological, skin sensitization, and antiviral properties [13]. In 2009, Majumdar developed a Pd(PPh3)4-catalyzed intramolecular C-H arylation reaction of benzenesulfonic acid 2-bromophenyl esters to afford polycyclic sultones, which are generally synthesized by elimination of the corresponding hydroxyl sulfonic acid derivatives, in up to 90% yield (Scheme 3.3, path a) [14]. TBAB was found to be critical in this reaction, and no reaction occurred in the absence of this additive. An electrophilic palladation mechanism was proposed for this transformation. 

TEA-C10-14 alkyl benzenesulfonate CAS 90194-42-6 EINECS/ELINCS 290-652-4 Synonyms Benzenesulfonic acid, mono-C10-14-alkyl derivs., compds. with triethanolamine C10-14-alkylbenzene sulfonate, triethanolamine salt Uses Surfactant in cosmetics TEA-C10-15 alkyl sulfate Synonyms Sulfuric acid. Cl 0-C15-alkyl esters, compds. with 2,2, 2"-nitrilotrisethanol Definition Triethanolamine salt of the sulfate of Cl0-15 alkyl sulfuric acid... 

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