Gold catalyzed synthesis of pyrrole and indole fused heterocycles via alkyne cyclization

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2015

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Aslan Taşkaya, Sultan

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New methodologies were developed for the synthesis of pyrrolo- and indolo-oxazin1-one derivatives. In the first section of this thesis, various N-propargyl pyrrole and indole esters were efficiently converted into corresponding carboxylic acids which then underwent intramolecular cyclization reaction with AuCl3 to give 6-exo-dig cyclization products. In the second part of the study, 6-exo-dig pyrrolo- and indolo- oxazinone derivatives were treated with TFA in order to achieve double bond isomerization. Some of the 6-exo-dig cyclic double bonds underwent isomerization to 6-endo-cyclic compounds upon treatment with TFA. The experimental results were supported by DFT calculations. Moreover, the cyclization reaction of 1-prop-2-ynyl1H-pyrrole-2-carboxylic acid in the presence of alcohols catalyzed by Au(I) resulted in the formation of hemiacetals after cascade reactions.

Subject Keywords

Pyrroles., Oxazoles., Indole., Gold., Catalysis.

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http://etd.lib.metu.edu.tr/upload/12618788/index.pdf
https://hdl.handle.net/11511/24678

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

S. Aslan Taşkaya, “Gold catalyzed synthesis of pyrrole and indole fused heterocycles via alkyne cyclization,” M.S. - Master of Science, Middle East Technical University, 2015.