Date of Award

2016

Document Type

Dissertation

Degree Name

Doctor of Philosophy (PhD)

Department

Chemistry

First Advisor

Stephen Everse

Abstract

This thesis describes the research conducted towards the overall goal of developing new synthetic organic methods to facilitate the synthesis of structurally complex nitrogen-containing polycyclic compounds. More specifically, I will describe the diverse reactivity of 1-aza-2-azoniaallene systems to make polycyclic diazenium salts and tetrahydropyridazine rings. I will also describe mechanistic studies undertaken to better understand this reactivity.

The Brewer research group has discovered that hydrazones undergo an oxidation reaction with chlorodimethylsulfonium chloride to afford -chloroazo compounds, which react intramolecularly with pendent alkene units to give bicyclic ring fused and bridged diazenium salts. My work includes a mechanistic study to understand how the reaction proceeds and what factors affect its outcome. I will also describe the development of a new method to make diazenium salts in a shorter and more efficient route using a hypervalent Iodine (III) reagent.

More recently, our group discovered new and different modes of reactivity of 1-aza-2-azoniaallene salts that included C-H amination reactions, polar [4 + 2] cycloadditions, electrophilic aromatic substitutions, and a chloroamination reaction. Our group was able to utilize these newly discovered reactivities in the preparation of pyrazolines, pyrazoles, tetrahydrocinnolines, and pyridazines, which are all complex compounds of great synthetic utilities that were made in short chemical transformations. Herein I describe my work to understand the scope and limitations of using these heteroallenes in the synthesis of pyridazines.

Language

en

Number of Pages

244 p.

Available for download on Tuesday, March 28, 2017

Included in

Chemistry Commons

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