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Ph.D. thesis 1970 from the Dept. of Physical & Inorganic Chemistry University of Adelaide / 152 leaves : ill., graphs / Title page, contents and abstract only. The complete thesis in print form is available from the University Library.

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It has been shown that photolysis of 4-azidopyridine N-oxide yields the singlet nitrene, which undergoes intersystem crossing at room temperature to generate triplet 4- nitrenopyridine N-oxide. The room temperature photochemistry is dominated by triplet nitrene chemistry leading to the formation of the azo-dimer. This unusual behavior is a result of selective stabilization of the lowest singlet state of the nitrene by the N-oxide group. In this study, we wish to investigate the effect of complexation of the N-oxide group with a metal cation on the kinetics and reactivity of 4-nitrenopyridine N-oxide and related compounds. It is envisaged that complexation will alter the polarity of the N-oxide bond making it less capable of spin delocalization in the nitrene. Complexation may be achieved through two different methods: complexation with cations in aqueous salt solutions and complexation of cations inside crown ethers. Crown ethers provide useful models due to the selectivity of complexation with different ions based on ring size and slower diffusion of cations away from the N-oxide group. Progress toward the multi-step synthesis of crown ethers containing the 4- azidopyridine N-oxide substructure is described herein. / Department of Chemistry

We have investigated the chemistry of 4-azidopyridine-N-oxide. One aspect of this thesis involved the photolysis of this azido heteroaromatic-N-oxide, to generate highly reactive nitrene intermediates. We have studied these intermediates and determined that the intermediates vary significantly in structure and reactivity from those of simpler phenyl and pyridyl systems. This study yields new insight into the structure, bonding, and energetics of nitrene species.The nitrene intermediate originating from this azide has features which could in the future help in synthetic practices and photoaffinity studies. It may aid in photoaffinity studies due to the fact that the N-oxide group imparts water solubility.This thesis investigates the premise that a change in the electronic nature of the aromatic ring results in a change in the systems reactivity. We are interested in whether changes in the nature of the ring in the azides induce large changes in the chemistry, and if so, whether they do so in a predictable manner.Another focus of the research involved 1,3-dipolar cycloaddition reactions with an azide, where a carbon-carbon double or triple bond will attach to an aromatic azide, 4-azidopyridine-N-oxide in this case, at the azido group (-N3) to generate new ring compounds. 1,3-dipolar cycloadditions are fascinating because the mechanism which takes place in the attachment phase is still under debate. These reactions were investigated by reacting 4-azidopyridine-N-oxide with an unsaturated compound (alkene or alkyne) and then analyzing the product mixtures by HPLC methods. / Department of Chemistry

ii, 181 leaves : ill. ; 25 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Dept. of Physical and Inorganic Chemistry, University of Adelaide, 1974

Thesis (Ph.D.) -- Dept. of Physical and Inorganic Chemistry, University of Adelaide, 1974.

Thesis (Ph. D.)--Brandeis University, 2000. / "UMI:9967593." MICROFILM COPY ALSO AVAILABLE IN THE UNIVERSITY ARCHIVES. Includes bibliographical references.