Reactivity of substituted 4-Pyridones in normal and inverse demand Diels-Alder cycloaddition
- UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
- Christopher J. MacNevin (Creator)
- Institution
- The University of North Carolina Wilmington (UNCW )
- Web Site: http://library.uncw.edu/
Abstract: The synthesis of the decahydroquinoline ring system has been explored extensively
due to its appearance within many biologically active natural alkaloids. New compounds
containing such a moiety are being discovered on an ongoing basis. The present work
has sought to develop an alternative synthetic pathway to this system through the use of
Diels-Alder [4 + 2] cycloaddition chemistry.
The initial focus of this research was on the development of an activated dienophile
derived from 4-pyridone. Two such compounds were eventually synthesized, N-tosyl-3-
formyl-5,6-dihydropyridin-4-one, and N-t-butoxycarbonyl-3-formyl-5,6-dihydropyridin-
4-one. The reactivity of these compounds with several different dienes was then
investigated in an effort to obtain the desired decahydroquinoline cycloadduct.
Under inverse electron demand Diels-Alder conditions, the synthesized compounds
reacted with ethyl vinyl ether to consistently produce pyran containing bicyclic adducts
under mild conditions. The products contained a mixture of isomers in varying ratio
relative to the nitrogen substituent present.
Non-activated dienes did not react with the dienophiles under normal demand
conditions even with the addition of lewis acid catalysts. However, cycloadducts were
formed through reaction with the highly activated diene 1-dimethylamino-3-tertbutyldimethylsiloxy-
1,3-butadiene. The products did not resemble the target
decahydroquinoline system but instead appeared to be the result of reaction with the
formyl group substituent, acting as a heterodienophile, to yield a dihydropyranone ring
bridged to C-3 of the original pyridone derived dienophile.
Reactivity of substituted 4-Pyridones in normal and inverse demand Diels-Alder cycloaddition
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Created on 1/1/2009
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Additional Information
- Publication
- Thesis
- A Thesis Submitted to the University of North Carolina Wilmington in Partial Fulfillment of the Requirements for the Degree of Master of Science
- Language: English
- Date: 2009
- Keywords
- Chemical reactions, Diels-Alder reaction, Diolefins, Ring formation (Chemistry)
- Subjects
- Diels-Alder reaction
- Ring formation (Chemistry)
- Diolefins
- Chemical reactions