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This dissertation, "Chiral Iron Pyridine Complexes and Ruthenium Complexes With N-heterocyclic Carbene and Macrocyclic (N, O) Donor Atom Ligands: Synthesis, Catalytic Activity and Biological Studies" by Kar-yee, Lam, 林嘉儀, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Abstract of thesis entitled CHIRAL IRON PYRIDINE COMPLEXES AND RUTHENIUM COMPLEXES WITH N-HETEROCYCLIC CARBENE AND MACROCYCLIC(N, O) DONOR ATOM LIGANDS: SYNTHESIS, CATALYTIC ACTIVITY AND BIOLOGICAL STUDIES Submitted by Lam Kar Yee For the degree of Doctor of Philosophy at The University of Hong Kong in April 2016 Transition metal complexes are widely applied as catalysts for organic transformation reactions such as the oxygen atom and nitrene transfer reactions and there is a growing interest to develop the medicinal applications of transition metal complexes. The studies of reactive metal-oxo and metal-nitrene intermediates are important in probing the underlying reaction mechanisms. This thesis is comprised of three main parts. In the first part, iron complexes with chiral pyridine ligands, such as 4′,6-disubstituted 2,2′ 6′,2″-terpyridine (NNN ) and 4′,6,6″-trisubstituted 2,2′ 6′,2″''-terpyridine (NNN ), were studied for their catalytic activities in asymmetric epoxidation, aziridination, amidation and sulfimidation reactions. The Fe-NNN complex catalyzed intermolecular nitrene transfer/CN bond formation reactions of styrenes with PhINTs in moderate product yields. For the asymmetric intramolecular amidation, the Fe-NNN complex can catalyze intramolecular C-N bond formation using PhI(OAc) as oxidant to form five- or six-membered ring products. The highest product yield obtained was 91 %. The complete conversion of para-substituted phenyl methyl sulfides to corresponding sulfimides was observed by using the Fe-NNN 1 2 complex as catalyst. Both the Fe-NNN and Fe-NNN complexes catalyzed asymmetric epoxidation of styrene using PhIO as oxidant at 0 C. The reaction intermediates of the nitrene/oxygen transfer reactions were studied by ESI-MS and high-valent iron-ligand multiple bonded species are proposed to be the reaction intermediates. In the second part, ruthenium pincer N-heterocyclic carbene (CNC) complexes were prepared and characterized by spectroscopic means and X-ray crystallography. II 2+ Complex [Ru (CNC)(bpy)(MeCN)], in which the CNC ligand adopts a fac-coordination mode and contains reactive CH bond of bridging methylene group, was found to react with PhINTs to result in the formation of a new CN bond and cleavage of one existing NC(methylene) bond of the CNC ligand, as revealed by X-ray crystal structure determination of the ruthenium complex product. The reaction 2+ of [Ru(CNC)(bpy)(MeCN)] with PhINTs was monitored by ESI-MS, UV-vis, and NMR spectroscopy; a paramagnetic Ru(III)-amido complex was isolated, which apparently resulted from intramolecular imido/nitrene CH insertion of a Ru(IV)-imido/nitrene intermediate and was found to undergo the observed CN bond cleavage. Such type of CN bond cleavage induced by metal-mediated imido/nitrene insertion is unprecedented in literature. The final part of this thesis is the study of the anti-angiogenic and anti-metastatic properties of the ruthenium complexes. Ruthenium complexes with different oxidation states (+2 and +3) and ligands (pincer NHC and macrocyclic (N, O) donor atom ligands) were examined for their cytotoxicity and anti-angiogenesis activity. III Among the complexes studied, [Ru (N O )Cl ]Cl (Ru-1) displays promising 2 2 2 inhibi