Benzenesulfonyl chloride, reaction with ethanol

A solution of 36 g. (0.2 mole) of benzenesulfonyl chloride in 100 ml. of dry pyridine is cooled to —8°, and 11.7 ml. (0.2 mole) of absolute ethanol (p. 142) is added slowly. The temperature is held in the range of —5 to —8° during the addition and for a total of 20-25 minutes. To the reaction mixture is added 250 ml. of 5 iV sulfuric acid which has been cooled to 3°. The mixture is also cooled during this operation. The mixture is then extracted with chloroform, and... 

Preparation. The reagent is prepared by the reaction of excess sodium azide in water-ethanol with benzenesulfonyl chloride. In an early procedure the latter reagent was dissolved in ethanol before addition to the sodium azide solution.1 In a more recent preparation, benzenesulfonyl chloride is added directly to the ethanolic solution of sodium azide.2... 

Theoretical studies of the gas-phase hydrolysis or methanolysis of methylsul-fonyl chloride indicated a concerted Sn2 process involving a four-membered cyclic transition state. The tertiary amine-catalysed hydrolysis of benzenesul-fonyl chloride was shown to be inhibited by chloride ion and a nucleophilic mechanism of catalysis was favoured. Kinetic studies" of the solvolysis of p-substituted benzenesulfonyl chlorides in aqueous binary mixtures with acetone, methanol, ethanol, acetonitrile and dioxime showed that the reactions were third order processes, with first order rate constants determined mainly by the molar concentrations of the protic solvent, so that the reaction rates appear to be dominated by solvent stoichiometry. The solvolyses in methanol and ethanol yield both an alcoholysis (ap) and a hydrolysis product (hp). Solvolyses of electron-rich arylsulfonyl chlorides, under neutral or acidic conditions, exhibited surprising maxima in solvent-dependent S values as defined by Equation 15. 

---