The kinetics of the reaction between acetic acid and epichlorohydrin in the presence of lithium, sodium and potassium acetates have been studied. The composition of the reaction mixture was followed chromatographically. Beside the two isomeric products of addition of epichlorohydrin to acetic acid, the presence was found of glycidyl acetate, glycerine dichlorohydrin and other products of parallel and subsequent reactions between the substrates and chlorohydroxyesters. A mechanism of the reaction, which takes into account the formation of the identified compounds has been proposed and a set of appropriate differential and balance equations developed. The rate constants for individual reactions as well as the catalysts used have been determined.

PRZEMYSLAW SANECKI and EDWARD ROKASZEWSKI. Can. J. Chem. 65, 2263 (1 987).A continuous polarographic method of recording instantaneous concentrations of -S02C1 groups in an aqueous acetic acid system containing CH3C02Na has been elaborated. Ten model monosulfonyl chlorides underwent hydrolysis according to pseudo-first order kinetics (20% H20, 80% V.V. CH3C02H, 0.5 mol x dm-3 CH3C02Na). Plots of hydrolysis for seven disulfonyl dichlorides with different number of -CH3 groups have been determined. Pseudo-first order rate constants for two consecutive reactions of hydrolysis (k, and k2) have been computed and the influence of -S02C1 and -SO; groups on the reactivity of the second group -S02CI has been discussed. The mechanism of nucleophilic substitution has also been discussed.PRZEMYSLAW SANECKI et EDWARD ROKASZEWSKI. Can. J. Chem. 65, 2263 (1987.On a dtveloppt une mtthode polarographique continue qui permet d'enregistrer instantantment la prtsence de groupements -S02C1 dans des systkmes aqueux d'acide acCtique contenant du CH3C02Na. Dix chlorures modkles de monosulfonyles ont subi une hydrolyse suivant une cinttique de pseudo-premier ordre (20% H20, 80% v/v de CH3C02H et 0,5 mol x dm-3 de CH3C02Na). On a determint les courbes d'hydrolyse de sept dichlomres de disulfonyles qui diffkrent par le nombre de groupements CH3. On a calcult les constantes de pseudo-premier ordre pour les deux reactions d'hydrolyse constcutives (k, et kZ) et on discute de l'influence des groupements -S02C1 et -SO; sur la rtactivitt du deuxikme groupement -S02C1. On discute aussi du mtcanisme de la substitution nucltophile.[Traduit par la revue] IntroductionThe solvolysis and hydrolysis of sulfonyl halogenides are subject of many papers (refs. 1-23 and references therein). The character of the investigations is closely linked with advances in knowledge on reaction mechanism as reported by Arrhenius, Bodenstein, Ingold, Winstein, Bronsted, and Hammett and co-workers. The titrimetric or conductometric methods were used in the determination of instantaneous concentrations of reagents or products, and spectral uv was used only in two cases.It has been found that monosulfonyl chlorides hydrolyze according to the SN2 mechanism (e.g. refs. 9, 10):

Three di-, (Gly),, (Val), and (Leu),, and one tetra-peptide, (Gly),, have been acylated with 2-chloroacetyl chloride and the resulting products treated with Cs2C03 in dimethylformamide (DMF) solution; (Gly), and (Leu), provided strained 9-membered rings whereas (Val), dimerized to the 18-membered ring.

The kinetics of reaction between acetic acid and epichlorohydrin carried out in the presence of DMF or DMSO was studied. In addition, the conductivity of the reaction mixture was measured. The conductivity was found to increase considerably as the reaction proceeded. This was explained in terms of the formation of new effective forms of catalysts: the ammonium salt (in case of DMF) or sulphonium salt (for DMSO). A reaction scheme has been proposed, taking into account the active catalyst forms. The set of kinetic equations describing the reaction has been developed and the appropriate rate constants evaluated.

PRZEMYS~AW SANECIU and EDWARD ROKASZEWSKI. Can. J. Chem. 66, 3056 (1988). Hydrolysis of 16 compounds C102S-Ar-B-Ar-S02C1 (B, bridge) in 20% H20, 8 0 8 v/v CH3C02H, 0.5 mol dmp3 CH3C02Na at 298.15 K has been investigated by a polarographic method. From plots of the hydrolysis, pseudo-first-order rate kl k2 constants for two consecutive reactions A -+ AI -+A2 have been computed and the influence of -SO2C1 groups, bridges B, and SO3-groups on the reactivity of -S02C1 groups has been discussed. The ratio of rate constants k2/k, ranges from 0.45 to 30, depending on the structure. Log (kl/(2kH)) correlated linearly with u-g:&HS and log (k,/kl) correlated linearly with ApK for the analogous diamine series H2N-Ar-B-Ar-NH2.PRZEMYSLAW SANECKI et EDWARD ROKASZEWSKI. Can. J. Chem. 66, 3056 (1988). Optrant i 298,15 K, en solution dans un mClange 20:80 (v/v) de H20/CH3C02H contenant 0,5 mol dm-) de CH3C02Na, et faisant appe1.i une mCthode polarographique, on a Ctudit I'hydrolyse de 16 composts du type C102S-S-Ar-B-Ar-S02C1 (pont, B). A partir des courbes d'hydrolyses, on a calculC les constantes de pseudo-premier ordre des deux rtactions kl k2 consCcutives A -+ Al -+ A2; on discute de l'influence des groupements -S02C1, des ponts B ainsi que des groupements SO3-sur la rkactivitt des groupements -S02CI. Selon la structure, les rapports des constantes de vitesse kz/kl varient de 0,45 i 30. On a Ctabli une corrklation lintaire entre le log (kl/2kH) et le u.g:&HS ainsi qu'entre le log (k2/kl) et le ApK de la skrie des diamines analogues H2N-Ar-B-Ar-NH2.[Traduit par la revue]