An investigation of the application of nucleophilic aromatic substitution by the SRN 1 mechanism of halobenzenesulfonamides and related compounds towards the synthesis of 1,2-benzothiazine I,I-dioxides is reported. 3-Substituted and 3,4- disubstituted 2<i>H</i>-l,2-benzothiazine l,l-dioxides were prepared in moderate to good yields via the photostimulated reaction of 2-halobenzenesulfonamides with ketone enolates. It was observed that with certain ketone enolates reduction to yield benzene sulfonamide competed with the substitution reaction. The presence of β-hydrogen atoms was a common structural feature of ketones used in reactions in which reduction competed with substitution. It was also observed that the amount of reduction product isolated increased as a function of the number of β-hydrogen atoms present on the ketone enolate. It was found that 2-bromo and 2-iodobenzenesulfonamide exhibit comparable reactivity with ketone enolates that do not possess β-hydrogen atoms. However, a marked decrease in the reactivity of 2-bromobenzenesulfonamide was observed when β-hydrogen atoms were present on the ketone enolate. / Ph. D.
Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/39245 |
Date | 25 August 2008 |
Creators | Layman, William Joseph |
Contributors | Chemistry, Wolfe, James F., Dillard, John G., Dorn, Harry C., Hudlicky, Tomas, Tanko, James M. |
Publisher | Virginia Tech |
Source Sets | Virginia Tech Theses and Dissertation |
Language | English |
Detected Language | English |
Type | Dissertation, Text |
Format | vii, 219 leaves, BTD, application/pdf, application/pdf |
Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
Relation | OCLC# 23657995, LD5655.V856_1990.L396.pdf |
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