Dissertation/Thesis Abstract

Synthesis, Reactivity, and Multi-Electron Redox Behavior of a Bis(phenoxy)amide Ligand Coordinated to a Tantalum Metal Center
by Zarkesh, Ryan A., Ph.D., University of California, Irvine, 2012, 150; 3494780
Abstract (Summary)

This dissertation describes the synthesis and reactivity of tantalum metal complexes containing a tridentate redox-active ligand. Fundamental studies have focused on utilizing the redox-active ligand to store multiple electron equivalents for oxidative addition and reductive elimination reactions.

Chapter 1 provides an introduction to the characteristics of redox-active ligands and provides an overview of group transfer reactions involving redox-active ligands. The previous published results of bidentate redox-active ligands coordinated to d0 metals are discussed in terms of their decomposition side reactions. Chapter 2 describes the coordination of a known tridentate redox-active bis(phenoxy)amide ligand, (ONO), to a d0 tantalum(V) metal center and the examination of the redox properties of the resulting chloro oxidation products by electrochemical and spectroscopic methods. Chapter 3 examines the reactivity of the (ONO)TaR 2 complexes in the general context of organometallic chemistry with a focus on protonolysis and reactivity with aryl azides, a known source of nitrene fragments upon oxidation. Chapter 4 examines the reactivity of the (ONO)TaX2 (X = Me, Cl) compounds with bulky diazoalkanes, a known carbene transfer reagent. The (ONO)TaCl2 complex proved to be a competent catalyst to generate cyclopropanes from styrene and the corresponding diazoalkane. Chapter 5 explores the utilization of the (ONO) ligand to store electron equivalents for the catalytic nitrene-nitrene coupling reactions with organoazides to afford organodiazenes. Finally, Chapter 6 addresses the electronic considerations of a related redox active triamido ligand in an effort to tune the ligand redox potentials.

Indexing (document details)
Advisor: Heyduk, Alan F.
Commitee: Borovik, Andrew S., Evans, William J.
School: University of California, Irvine
Department: Chemistry - Ph.D.
School Location: United States -- California
Source: DAI-B 73/06, Dissertation Abstracts International
Subjects: Inorganic chemistry
Keywords: Bis(phenoxy)amide, Early transition metals, Nitrogen-nitrogen bond formation, Redox-active ligands, Tantalum
Publication Number: 3494780
ISBN: 978-1-267-17110-8
Copyright © 2020 ProQuest LLC. All rights reserved. Terms and Conditions Privacy Policy Cookie Policy