Date of Award
1994
Degree Type
Dissertation
Degree Name
Doctor of Philosophy
Abstract
This thesis contains three chapters dealing with the organic chemistry of sulfonyl and carbonyl compounds. The first chapter describes the synthesis and rate studies of a series of {dollar}\beta{dollar}-methoxy sulfones and their unsubstituted parent compounds designed to test some basic ideas of the nature of the electronic effects of substituents in saturated systems. The substrates were designed to illustrate the effect of the change of the H{dollar}\sb\alpha{dollar}-C{dollar}\sb\alpha{dollar}-C{dollar}\sb\beta{dollar}-O dihedral angle on the rate of base-promoted H-D exchange reaction. The presence of a {dollar}\beta{dollar}-methoxy group affected the H-D exchange rates by factors varying from a few hundred to greater than ten thousands. This study leads to the conclusion that the effect of a {dollar}\beta{dollar}-alkoxy substituent cannot be accounted for by the conventional polar effect (i.e. inductive and field effects), but must involve a kinetic anomeric effect.;The second chapter describes synthesis, hydrolysis, and p{dollar}K\sb{lcub}\rm a{rcub}{dollar} determination of sulfonamides and sulfonimides. Ethane-1,2-disulfonimide has been synthesized for the first time. More than twenty other sulfonamides and sulfonimides were synthesized to examine the effect of ring strain and a stereoelectronic effect in acidities and hydrolysis rates. It has been found that the acidities of five-membered cyclic sulfonimides are one to two orders of magnitude greater than six-membered cyclic sulfonimides or acyclic sulfonimides. It has also been found that ethane-1,2-disulfonimide hydrolyses 430 times faster than its six-membered analogue, propane-1,3-disulfonimide, and 320 times faster than its open chain analogue, dimethanesulfonimide.;In the third chapter pH optimization in acyl transfer has been described. The reaction of amines with Ac{dollar}\sb2{dollar}O in water gave variable yields of the N-substituted acetamide. From the p{dollar}K\sb{lcub}\rm a{rcub}{dollar}'s of the amines and {dollar}k\sb{lcub}\rm w{rcub}{dollar} and {dollar}k\sb{lcub}\rm OH{rcub}{dollar} for Ac{dollar}\sb2{dollar}O, both {dollar}k\sb{lcub}\rm DN{rcub}{dollar} and {dollar}k\sb{lcub}\rm GB{rcub}{dollar} may be readily evaluated by fitting the pH-yield data to pH-yield or pH-product ratio profiles. The extent of general base catalysis is evidently dependent on the amount of steric hindrance and the pK{dollar}\sb{lcub}\rm a{rcub}{dollar} of the amine. The reactions of PhCOCl with PhCH{dollar}\sb2{dollar}NH{dollar}\sb2{dollar} and piperidine in aqueous solution show no sign of the general base assisted hydrolysis. A general equation for obtaining the maximum yield in competition with hydrolysis is presented and verified with the benzoylation and acetylation reactions.
Recommended Citation
Guo, Zhen Rong, "Mechanistic And Synthetic Investigations In Sulfonyl Chemistry And Acyl Transfer" (1994). Digitized Theses. 2370.
https://ir.lib.uwo.ca/digitizedtheses/2370