Publication Date
2019
Document Type
Dissertation/Thesis
First Advisor
Klumpp, Douglas A.
Degree Name
Ph.D. (Doctor of Philosophy)
Legacy Department
Department of Chemistry and Biochemistry
Abstract
This dissertation describes the use of triflic acid as a catalyst in organic synthesis. The first chapter is an introduction of reaction classes, reactive intermediate, and superacids.
Chapter 2 discusses a series of compounds have been prepared by the Fischer indole synthesis and Friedel–Crafts reactions, using a single acid catalyst in a one-pot conversion. The reactions have worked best with pyridyl-substituted hydrazones/indoles. Chlorination and bromination products are formed in good yields and high regioselectivities. Acylation products have also been prepared by the two-stage reaction. In the case of alkylation, the expected alkyl-substituted indoles are obtained however they are accompanied by over-alkylation products.
In chapter 3, Diels−Alder reactions have been accomplished with ethylene as the dienophile through the use of inverseelectron demand Diels−Alder chemistry. As a key aspect of the chemistry, the dienes are part of tri- or dicationic superelectrophilic systems. Theoretical calculations reveal that the highly charged superelectrophiles possess exceptionally low lying LUMOs, and this facilitates the cycloaddition chemistry with ethylene. The chemistry has been
used to prepare a series of tetrahydroquinoline products. This represents the first application of superelectrophilic activation in a cycloaddition reaction and a new method of utilizing ethylene as a C2 building block.
In chapter 4, heterocyclic imines provide biaryl products by a two-step transformation. The first transformation involves a Diels–Alder reaction with a multiply protonated imine to give a tetrahydroquinoline product, whereas the second step involves oxidation with elemental sulfur at 260°C.
In chapter 5, a series of heterocyclic enones is prepared for heterocyclic indanones synthesis through superelectrophilic Nazarov cyclization. Kinetic studiesrevealsuperelectrophiles enhanced the reaction rate by two folds. A series of cinnamic acid derivatives were used to synthesize substituted indanone in one pot reaction.
Chapter 6, a series of quinoline derivatives have been synthesized in superacid promoted reactions. The key step of this procedure involves aromatization by the elimination of hydrochloric acid or benzene- occurring through ipso-protonation at the phenyl group. The chemistry utilizes rapidly available anilines and α, β unsaturated carbonyl compounds.
Recommended Citation
Vuong, Hien Quoc, "Utilization of Superelectrophiles in Organic Synthesis" (2019). Graduate Research Theses & Dissertations. 7759.
https://huskiecommons.lib.niu.edu/allgraduate-thesesdissertations/7759
Extent
213 pages
Language
eng
Publisher
Northern Illinois University
Rights Statement
In Copyright
Rights Statement 2
NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.
Media Type
Text
