Sulphonate esters sulphonates

Phenylhydrazine condenses with acetoacetic ester to give a pyrazolone derivative which on methylation gives phenazone. The sulphonic acid similarly gives rise to the tartrazine dyestuffs. It is used to make indole derivatives by the Fischer process. 

A) Toluene -sulphonates. For directions, using an acetone solution of toluene-/) Sulphonyl chloride, see p. 249 use o 3-o 5 g. of the phenol. Note that the chloride should be dissolved in a minimum of acetone, otherwise separation of the ester may be slow and incomplete. 

For some phenols whose esters are readily hydrolysed, it is advantageous to add the powdered chloride to a pyridine solution of the phenol, warm the mixture on the water-bath for ca. 15 minutes, cool and pour into water, when the sulphonate will separate. 

The preparation of the phenacyl-, />-bromophenacyl or />-nitrobenzyl esters of sulphonic acids is usually unsatisfactory. 

To prepare the free sulphinic acid, dissolve some of the sodium salt in cold water and cautiously acidify with hydrochloric acid avoid an excess of mineral acid since it dissolves the sulphinic acid to a certain extent. The resulting p-tolueneaulphinic acid is difflcult to dry without partial conversion into the sulphonic acid and thiolsulphonic ester... 

RCH(OH)=CHCOR or -keto esters RCH(OH)=CHCOOR ) dissolve in dilute sodium hydroxide solution, i.e., contain an acidic group of sufficient strength to react with the alkah. Carboxyhc acids and sulphonic acids are soluble in dilute solutions of sodium bicarbonate some negatively-substituted phenols, for example, picric acid, 2 4 6-tribromo-phenol and 2 4-dinitrophenol, are strongly acidic and also dissolve in dilute sodium bicarbonate solution. 

The alkyl esters of sulphonlc acids exhibit properties similar to those of the alkyl sulphates, and are hydrolysed, by boiling with aqueous alkalis, to the alcohols and sulphonates. Thus with ethyl p-toluenesulphonate ... 

S. Patai and Z. Rappoport, eds.. The Chemistry of Sulphonic Acids, Esters and Their Derivatives, John Wiley Sons, Ltd., Chichester, U.K., 1991. 

A number of basic materials such as hydroxides, hydrides and amides of alkaline and alkaline earth metals and metal oxides such as zinc oxide and antimony oxide are useful catalysts for the reaction. Acid ester-exchange catalysts such as boric acid, p-toluene sulphonic acid and zinc chloride are less... 

Amongst the catalysts described in the literature may be mentioned dimethylbenzylamine, dimethlylcyclohexylamine, diethylaminoethanol, Walkylmorpholines and the adipic acid ester of A-diethylaminoethanol. A number of proprietary products of undisclosed composition have also been successfully employed. Emulsifiers include sulphonated castor oil and structure modifiers such as ammonium oleate and silicone oils. 

Combined Erythrina Alkaloids. The sources of the liberated alkaloids (see above) are now known to be, at least in two cases, the sulphur-containing alkaloids erysothiopine and erysothiovine, which are esters of sulphoacetic acid, HOOC. CHj. SOj. OH, identified as the aniline salt, m.p. 187-9° with erj sopine and erysovine respectively. The sources of erysodine and erysonine have not yet been isolated. These combined alkaloids arc believed to be sulphonic esters, of the type HO. OC. CHj. SOj. 0. R, where R is the alkaloidal residue. ... 

Perfluoroalkanesulfomc Acids and Their Derivatives (Russ ) Huang, W, Chen Q Chern Sulphonic Acids, Esters, Their Derivatives 903-946 157... 

Rust inhibitor T0 eliminate rusting in presence of moisture Polar compounds, such as metallic soaps, esters and derivatives of dibasic acids barium and calcium sulphonates... 

The kinetics of alkylation of aromatics with sulphonic acid esters have been... 

Trost found126 that aryl sulphones containing a range of other functionalities could be successfully desulphonylated without attack at alkenes, esters or nitriles, and without any detectable degree of alkene migration. 

Benzyltriethylammonium permanganate has also been used for the mild oxidation of sulphoxides to sulphones at — 10 °C in methylene chloride in the presence of keto, amino and ester groups in > 65% yields142. 

An excellent discussion on derivatization techniques has been given by Lawrence (17) including a detailed discussion on pre-column derivatization (18) and post-column derivatization (19). Probably, the more popular procedures are those that produce fluorescing derivatives to improve detector sensitivity. One of the more commonly used reagents is dansyl chloride (20), 5-dimethylamino-naphthalene-1-sulphonyl chloride (sometimes called DNS-chloride or DNS-C1). The reagent reacts with phenols and primary and secondary amines under slightly basic conditions forming sulphonate esters or sulphonamides. 

Despite the aversion of the sulphonyl group to function as a nucleophile, there are a limited number of literature reports that deseribe sueh a process . The first of these does not lead to a reduetion at sulphur and is thus not direetly relevant, but the report by Braverman and Duar deseribes reaetions in whieh an acetylenie sulphinate ester ean undergo a [2,3] sigmatropie rearrangement to an allenie t-butyl sulphone. Reaetion of this sulphone with the appropriate eleetrophile, for example bromine, gave a y-sultine, formation of whieh requires the partieipation of the sulphonyl group in an intramoleeular cyclization process. The reactions are outlined in equation (40). 

Shortly thereafter, Kuo, Aoyama and Shioiri described essentially the same procedure for the desulphonylation of a-benzylsulphonylacetate esters. They acknowledged their procedure as being due to Tsuchihashi, who had described it previously in conference proceedings and in a Japanese patent. The reactions are structure- and reagent-dependent, as illustrated in equations (47) and (48). Yields ranged from 49 to 78%. The sulphone used in equation (47) also gave some dibenzyl sulphone with sodium and ethanol in THF. 

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