Synthesis And Mechanism In Organic Sulfonyl Chemistry

This thesis describes four topics in synthesis and mechanism of reactions of certain organo-sulfonyl compounds. The first describes the reaction of thiirane-1,1-dioxide with hydroxide ion. Notwithstanding an earlier report, it was found that the major product of this reaction was ethanesulfonate anion, substituted analogues of which have occasionally been observed as products of certain Ramberg-Backlund reactions. It is proposed that the reaction proceeds via a penta-coordinated sulfur intermediate formed by the attack of hydroxide ion at the sulfonyl function of thiirane-1,1-dioxide.;In the second study, use of {dollar}\sp{lcub}18{rcub}{dollar}O labels and kinetics led to the conclusion that hydrolysis of 2-hydroxyethanesulfonyl chloride to 2-hydroxyethanesulfonate proceeded (a) predominantly via the four-membered ring intermediate {dollar}\beta{dollar}-sultone, and (b) with S-O bond cleavage of {dollar}\beta{dollar}-sultone rather than the normal C-O cleavage of sulfonate esters. This observation is discussed in terms of a new stereoelectronic effect.;The next topic concerns the synthesis of 2-(phenylthio)ethanesulfonyl chloride, which two other research groups had previously failed to isolate. Rate constants were measured for its facile thermal transformation into 2-phenylthioethyl chloride, and their variation with solvent polarity taken as evidence for the intermediacy of the episulfonium ion in this reaction.;In the last topic, reaction of sulfonyl chlorides of the type XCH{dollar}\sb2{dollar}CH{dollar}\sb2{dollar}SO{dollar}\sb2{dollar}C{dollar}\ell{dollar} with pyridine was found to exhibit multiple reaction pathways depending upon the group X. Whereas an excellent leaving group X eliminated initially to form ethenesulfonyl chloride, which then reacted further via an S{dollar}\sb{lcub}N{rcub}{dollar}2{dollar}\sp\prime{dollar} mechanism, mediocre and poor leaving groups caused the substrates to react initially via a sulfene with the X group present. The mediocre groups were then partly lost in the sulfene trapping step; in the presence of neopentyl alcohol, the amount of neopentyl ethenesulfonate formed correlated with the nucleofugality of each X group, enabling an extension of Stirling\u27s nucleofugality scale