by Lam Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 70-75). / Acknowledgements --- p.i / Abbreviations --- p.ii / Abstract --- p.iii / Introduction --- p.1 / Results and Discussion --- p.16 / Conclusion --- p.55 / Experimental --- p.56 / References --- p.70 / Appendix --- p.76 / List of Spectra --- p.80

by Won Hon Kit. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 66-70). / by Won Hon Kit. / Acknowledgment --- p.i / Abstract --- p.ii / Chapter Chapter1 --- Introduction --- p.1 / Chapter 1.1 --- Uniqueness of ZnxCd/1-x Se --- p.1 / Chapter 1.2 --- The Choice of OMVPE --- p.1 / Chapter 1.3 --- Epilayer Relaxation in Heteroepitaxy --- p.2 / Chapter 1.4 --- The Most Suitable Substrate --- p.4 / Chapter Chapter2 --- Experimental Procedures --- p.6 / Chapter 2.1 --- Degreasing and Etching --- p.6 / Chapter 2.2 --- Preheating --- p.6 / Chapter 2.3 --- OMVPE Growth --- p.6 / Chapter Chapter3 --- Characterization --- p.9 / Chapter 3.1 --- X-ray Diffraction --- p.9 / Chapter 3.2 --- EDX Spectroscopy --- p.13 / Chapter 3.3 --- Optical Reflectance --- p.15 / Chapter Chapter4 --- Data Analysis --- p.20 / Chapter 4.1 --- Control of Composition --- p.20 / Chapter 4.2 --- Structural Quality and Epilayer Relaxation --- p.22 / Chapter 4.3 --- Critical Point Energies --- p.24 / Chapter 4.4 --- Refractive Index and Extinction coefficient --- p.26 / Chapter Chapter5 --- Conclusions --- p.28 / List of Figures --- p.30 / Reference --- p.66

<p>It is well-known that f-block elements can exhibit coordination modes which surpass those of the transition metals. With uranyl and uranium bis(imido) complexes a strong preference is shown for the oxo or imido ligands in the <i>trans-</i> position; a phenomenon which is known as the inverse trans- influence which is unique to high valent actinides. However, when a third imido is added to the complex, a decrease in bond order occurs and this preference is diminished. Through the synthesis of several novel coordination complexes of tris(2,6-diisopropylphenyl)imido uranium [U(NDipp)₃] with a variety of ligands, we were able to analyze the energy differentials between bonding modes in both the solution and solid state. Furthermore, density functional theory calculations were employed to model the energetic preferences between these geometries. The combination of analyses gives rise to the observation that the orientation of the imido substituents is fluxional depending on the rigidity of the supporting ligands, and oftentimes exhibits low energetic barriers for the formation of different conformers.</p> <p> Uranium tris(imido) species bearing <i>trans</i>-imidos are desirable synthons as they can be used to mimic reactivity of more complicated uranium oxide polymeric systems. Such systems are advantageous as they are easily soluble in organic solvents, making them amenable to standard characterization methods and ligand substitution strategies. Our group has previously shown that uranium tris(imidos), easily synthesized from [(^MesPDI^Me)U(THF)]₂ and various azides, feature axial imido substituents exhibiting differing bond characteristics than the adjacent equatorial imido substituent. The aim of this work is to show that multiple analogues of mixed imido products can be formed from either the aforementioned dimer or stable tris(imido) synthons by exploiting reactivity differences between the axial and equatorial positions. </p> Presented herein are novel copper-​catalyzed ring opening reactions of cyclopropanols and various electrophiles to synthesize a variety of beta-​functionalized ketones. The reactions feature mild conditions and tolerates a wide selection of functional groups leading to complex products which can be used in the synthesis of bioactive molecules.

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Organometallic complexes containing transition metals, such as Ru(II), Os(II), Ir(III), have been moderately and recently used in medicinal chemistry as anticancer, antimalarial, antimicrobial or diagnostic agents. Current trends have led researchers to explore and define new synthetic methods in the quest for the design of new drugs and reduce the inherit associated toxic side-effects by using metal based compounds. Ferrocene based derivatives have been subjected to study for their biological and medicinal applications. Examples include ferrocenophane polyphenol, ferrocenyl quinone methides, ferrocenyl-aminoquinoline-carboxamide and a ferrocene-substituted hydroxytamoxifen, which has been proved as a potential new breast cancer therapeutic. Ferroquine displays antimalarial activity and ferrocifen is a tamoxifen-ferrocene anticancer agent. During the course of our research, we have focused on synthesizing and studying the biological activity of novel organometallic compounds containing the corresponding ferrocene moiety. We aimed to make, at least, 3 different families of compounds, which were cannabinoid receptor (CB1/CB2 receptor agonists), histone deacetylase (HDAC) selective inhibitors and general kinase inhibitors. Firstly, a review covering the state-of-the-art in bioorganometallic chemistry will be presented. Secondly, we started with the synthesis of a small library of compounds containing the following groups: ferrocenylamine, 4-oxo-1, 4-dihydropyridine and dihydroquinoline. We used aminoferrocene as a bioisostere of the adamantylamine group where previous studies of compounds containing the latter group had showed it to effectively interact with the cannabinoid receptors, CB1 and CB2. Some of our compounds displayed good to excellent potency in the nM range against the CB1 and CB2 receptors. Thirdly, we embarked to synthesise HDAC inhibitors knowing their potential as anti-cancer drugs and trying to obtain, wherever possible, enzyme isoform selectivity. One of the well-known HDAC inhibitors is suberoylanilide hydroxamic acid (SAHA). Vorinastat, as it is also known, has received Food and Drug Administration approval for treating patients with cutaneous T-cell lymphoma. The compound developed in our group by replacing ferrocene for the phenyl ring in SAHA, called JAHA, is another example of a highly potent HDAC inhibitor. Our research led to compounds where the hydroxamic acid moiety in JAHA has been replaced by a benzamide group. This transformation has produced a significant effect in delivering a potent HDAC3 selective HDAC inhibitor. This is supported by biological studies and a molecular modelling rationalisation. Next, a series of oxindole based analogues have been synthesized by the Knoevenagel condensation reaction of: 5-(pentafluorosulfanyl)-1,3-dihydro-indol-2-one and 6-(pentafluorosulfanyl)-1,3-dihydro-indol-2-one compound with: ferrocenecarboxaldehyde and pyrrole-2-carboxaldehyde. The compounds thereby synthesised have been studied against a panel of kinases, and kinase inhibitory data will be discussed and presented. In a Future directions section, we will describe the synthesis of FAAH (fatty acid amide hydrolase) inhibitors based on an aminoferrocene backbone.

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Thesis (Ph. D.)--University of Hong Kong, 2006. / Title proper from title frame. Also available in printed format.

The objective of this thesis is to explore quinoline and pyridine functionalized multidentate ligand systems that are capable of accommodating two metal species and to study the reactivity of the resulting bimetallic complexes, in the aim of investigating potential synergistic effects between the metal centres. A series of functionalized 1,2,4,5-tetrakis(quinolin-8-yl)benzene ligands were synthesized. The dinuclear platinum complexes of these ligands could activate C-Cl bonds of chlorinated solvents and dearomatize the central benzene ring of the ligand concurrently. A series of extended ligands where the central benzene ring was replaced by trans-stilbene, diphenylacetylene and pyrene groups were synthesized in order to explore more ligand-based reactivity. Two dinuclear diphenylplatinum complexes were synthesized. A series of mono- and bis-quinolinyl functionalized thiophene ligands have also been synthesized. Dinuclear platinum complexes of the bisquinolinyl thiophenes were isolated, which represented the first group 10 metal complexes of η2-thiophene, a long sought-after intermediate relevant to the hydrodesulfurization (HDS) process. Oxidation of these diplatinum complexes by MeOTf led to the isolation of mononuclear chiral five-coordinate platinum(IV) complexes, and a ligand twisting mechanism of these complexes was proposed on the basis of dynamic NMR studies and DFT calculations to elucidate the interconversion of two enantiomers. The reactions of monoquinolinyl functionalized thiophenes and [Pt(CH3)2(SMe2)]2/[PtH(dippe)]2 led to selective C-H/C-S bonds activation of the thiophene moieties respectively. A luminescent U-shaped bis-dipyridylamine functionalized anthracene ligand was designed and synthesized. This compound was fabricated into OLED devices and shown to be a promising emissive material. As a ligand, it adopted different coordination modes, acting as either binucleating double bidentate ligand, or mononucleating tetradentate ligand. Three dirhodium, dizinc and monozinc complexes were synthesized. Pyridine and phosphine functionalized 4,5-diazafluorene ligands were synthesized and the former ligand served as a mononucleating ligand via the two nitrogen donor atoms of the diazafluorenyl moiety while the latter ligand could act as a binucleating ligand via the phosphorus donor atom, two nitrogen donor atoms and the carbon donor atom. Several Ru, Rh, Pt, Cu and Au complexes were synthesized, and two Pt-Pt, Pt-Cu bimetallic complexes were isolated and characterized based on the phosphine functionalized ligand.