Nucleofugality effects in the pyridine promoted formation of esters from 2-substituted ethanesulfonyl chlorides

Abstract

109 (1988). The products of reaction of a series of 10 2-substituted ethanesulfonyl chlorides, X-CH2CH2S02C1 (I), with neopentyl alcohol and pyridine-d5 in nitromethane-d3 showed three reaction pathways depending on the nucleofugality of the substituent, X. These routes lead, respectively, to (i) the corresponding neopentyl ester (4), via the sulfene (3) (low substituent nucleofugality); (ii) a mixture of ester 4 and neopentyl ethenesulfonate (5), by the same route except for a partial loss of the 2-substituent during trapping of the sulfene (3) (intermediate nucleofugality); and (iii) a mixture of the ethenesulfonate (5) and the pyridino-betylate (4g) esters, arising from initial elimination of HX to form ethenesulfonyl chloride (2) followed by its further reaction (high substituent nucleofugality). A set of nucleofugality values closely related to, and partly complementing, those derived by Stirling and co-workers can be estimated from the product ratios in those reactions proceeding (at least in part) by route (ii) above. Old reports of anomalous products from 1,2-ethanedisulfonyl chloride (li) and 2-chloroethanesulfonyl chloride (lj) are simply accounted for on the basis of the initial conversion to ethenesulfonyl chloride (2).JAMES FREDERICK KING, JOHN HENRY HILLHOUSE, TOYANNE MARIE LAURISTON et KISHAN CHAND KHEMANI. Can. J. Chem. 66, 1109Chem. 66, (1988.Les produits provenant des rkactions d'une sCrie de 10 chlorures d'tthanesulfonyle substituCs en position 2, X-CH2CH2S02CI (I), avec I'alcool nCopentylique et la pyridine-ds, dans le nitromkthane-d3 proviennent de trois voies differentes qui dtpendent de la nuclCofugacitt du substituant X. Ces voies conduisent respectivement 21 (i) ester nCopentylique correspondant (4), par la biais du sulfene 3 (lorsque la nuclCofugacitC du substituant est faible); (ii) un milange de I'ester 4 et I'tth2nesulfonate de ntopentyle (5) qui proviennent de la m&me voie, except6 pour la perte partielle du substituant en position 2 qui se produit lors du piCgeage du sulf5ne 3 (lorsque la nuclCofugacit6 du substituant est intermkdiaire); et (iii) un melange des esters Cth5nesulfo-nate (5) et pyridinio-Etylate (4g) qui proviennent d'une Climination initiale de HX, conduisant au chlorure d'Cth5nesulfonyle (2), qui est suivie de sa &action (lorsque la nuclCofugacitC du substituant est ClevCe). En se basant sur les rapports des produits qui se foment au cours des rkactions (au moins en partie) qui suivent la voie (ii) mentionnCe plus haut, on peut tvaluer un ensemble de valeurs de nucltofugacitt qui ressemble et qui compl2te celui de Stirling et ses collaborateurs. Des rapports antCrieurs concernant la formation de produits anormaux a partir des chlorures d'Cthanedisulfonyle-1,2 (li) et de chloro-2 Cthanesulfonyle (lj) peuvent facilement &tre expliquCs en se basant sur une conversion initiale en chlorure d'eth2nesulfonyle (2).[Traduit par la revue] 1

Chemoselective Reactions of Functionalized Sulfonyl Halides

“…To be more specific, acid‐promoted dehydration of amides [207,299] and β‐hydroxycarbonyl compounds, [207,299] dehydrochlorination [300,301] or ‐bromination [302] in the presence of a base were reported (Scheme 43). In addition to that, nucleophile‐promoted SO 2 /HCl elimination of one of two SO 2 Cl groups present in the substrate molecule (formally as SO 2 /HCl) with further nucleophilic attack at the remaining one was reported [303,304] …”

“…In addition to that, nucleophile-promoted SO 2 / HCl elimination of one of two SO 2 Cl groups present in the substrate molecule (formally as SO 2 /HCl) with further nucleophilic attack at the remaining one was reported. [303,304] Cycloadditions and heterocyclizations. Due to the high reactivity of sulfonyl chlorides, the scope of cycloadditions and Scheme 36.…”

Vinylogous nucleophilic catalysis. The tertiary amine promoted reaction of ethenesulfonyl chloride with alcohols

“…Instrumentation, methods, and provenance of most of the starting materials and comparison compounds have been previously described (2,12,17).…”

“…To find out what had happened to the rest of the material, we examined the product directly by 'Hrnr, which showed the presence of about 60% of the ester (5, R = Pri) along with another product (-40%), which appeared to be Me3N+CH2CH2S020Pri C1-(6), i.e. what we subsequently called the [2]betylate ester (17); this was verified by synthesis of 6. Since the betylate 6 was found to be converted to 5 with aqueous sodium carbonate, the conversion of 1 into 5 was then readily carried out in good yield (>go%) by incorporating a sodium carbonate wash in the work-up (17).…”

“…Evidence for the principal pathway For reasons detailed elsewhere (2), the more recent experiments were carried out with neopentyl alcohol in CD3N02. Reaction of 1 with pyridine-d5 and the alcohol for 1 min at 37°C gave a mixture of 5 (R = Np) and the betylate (lob), in the ratio 67:33.…”