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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Conjugated macrocycles based on phenanthrene: from syntheses to applications. / 構建以菲為基本單元的共軛大環: 從合成到應用 / Gou jian yi fei wei ji ben dan yuan de gong e da huan: cong he cheng dao ying yong

January 2010 (has links)
Zheng, Xing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract --- p.iii / 摘要 --- p.iv / Acknowledgements --- p.v / Table of Contents --- p.vi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Macrocycles based on Phenanthrene - Syntheses and Applications --- p.31 / Chapter 1. --- Project Aim and Molecule Design --- p.31 / Chapter 1.1. --- Project Aim --- p.31 / Chapter 1.2. --- Design of Molecules --- p.31 / Chapter 2. --- Synthesis of Macrocycles with Different Linkages --- p.37 / Chapter 2.2. --- Synthesis of Macrocycle with Monoacetylene Units as Linkages --- p.38 / Chapter 2.3. --- Synthesis of Macrocycle with Carbon-Carbon Double Bond as linkages --- p.45 / Chapter 2.4. --- Synthesis of Macrocycle with Carbon-Carbon Singe Bond as Linkages --- p.48 / Chapter 2.5. --- Synthesis of Macrocycle with Mixed Diacetylene and Acetylene Units as Linkages --- p.49 / Chapter 2.6. --- Synthesis of Macrocycle with Diacetylene Units as Linkages without Side Chains --- p.52 / Chapter 3. --- Characterization and Application of Macrocycles based on Phenanthrene --- p.53 / Chapter 3.1. --- Self-assembly of Macrocycles 2.1 --- p.53 / Chapter 3.2. --- Induced Ring Currents in Phenanthrene-Fused Dehydroannulenes --- p.58 / Chapter 3.3. --- Application as Fluorescence Sensors for Explosives --- p.62 / Chapter 3.4. --- Application as Organic Semiconductors --- p.62 / Chapter 3.5. --- Application as Precursors in Attempted Synthesis of Carbon Nano Belt and Polymeric Nanotubes --- p.64 / Chapter 4. --- Experiment --- p.68 / Appendix --- p.93
2

Synthesis of macrocyclic 1,3-diketones from metacyclophanes and their applications in organic synthesis.

January 1994 (has links)
by Siu-leung Ng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 61-62). / Acknowledgments --- p.i / Content --- p.ii / List of Schemes --- p.iii / List of Tables --- p.iv / List of Spectra --- p.v / Abstract --- p.viii / Abbreviations --- p.x / Chapter I. --- Introduction --- p.1 / Chapter II. --- Literature survey / Chapter II.1. --- Ring expansion of cyclic enamines via a [2+2]cycloaddition --- p.4 / Chapter II.2. --- The Ito-Saegusa protocol --- p.6 / Chapter II.3. --- "The Suzuki-Watanabe-Noyori palladium(0)-catalyzed ring opening of cyclic α,β-epoxy ketones" --- p.7 / Chapter III. --- Synthetic plan --- p.9 / Chapter IV. --- Results and discussion / Chapter IV. 1. --- General routes to [n]metacyclophanes (24) and (n+2)- methoxy[n]metacyclophane 35 --- p.15 / Chapter IV.2. --- Birch reduction of 24 and 35 and ozonolvsis of 25 and 36 --- p.17 / Chapter IV.3. --- Synthetic applications / Chapter IV.3.1. --- Synthesis of heterocyclophanes --- p.27 / Chapter IV.3.2. --- Synthesis of exaltone (8) --- p.28 / Chapter V. --- Conclusion --- p.30 / Chapter VI. --- Experimental --- p.31 / Chapter VII. --- References --- p.61 / Chapter VIII. --- 1H and 13C NMR spectra of selected compounds --- p.63
3

Synthesis of [beta]-ketomacrolides via 1-oxa[n]meta-cyclophanes and a new route to (+-)-patulolide C.

January 1994 (has links)
by Fong Sun. / On t.p., "+" appears over "-". / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 41-43). / Acknowledgements --- p.i / Contents --- p.ii / Abstract --- p.iii / Abbreviations --- p.iv / Chapter I --- Introduction / Chapter I-1 --- General background --- p.1 / Chapter I-2 --- Literature survey --- p.3 / Chapter I-2-1 --- Ley's approach to β-ketomacrolides --- p.3 / Chapter I-2-2 --- Weiler's approach to β-ketomacrolides --- p.4 / Chapter I-2-3 --- Macrocyclic β-ketomacrolides formation through sulfide contraction ´ؤIreland's approach --- p.5 / Chapter II --- Result and Discussion / Chapter II-1 --- General strategy for the synthesis of 1 -oxa[n]metacyclophanes --- p.7 / Chapter II-2 --- l-Oxa[n]metacyclophanes as masked β-ketomacrolides synthons --- p.9 / Chapter II-3 --- Application to the synthesis of natural products --- p.10 / Chapter II-4 --- An alternate approach for the synthesis of (2E)-2-dodecen-l 1-olide´ؤA structural proof --- p.15 / Chapter III --- Conclusion --- p.17 / Chapter IV --- Experimental --- p.18 / Chapter V --- References --- p.41 / Chapter VI --- Spectra --- p.44
4

Part I, chemoselective and oxo-controlled s-oxidation of sulfides containing pyridine rings and olefinic double bonds: Part II, directed synthesis of all-Homocalix(n)arenes with various cavity sizes. / Chemoselective and oxo-controlled s-oxidation of sulfides containing pyridine rings and olefinic double bonds / Part II. directed synthesis of all-Homocalix(n)arenes with various cavity sizes / Directed synthesis of all-Homocalix(n)arenes with various cavity sizes

January 1999 (has links)
Ho-Fai Lee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 90-91). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abbreviations --- p.ii / Abstract --- p.iii / Chapter Part I. --- Chemoselective and Oxo-Controlled S-Oxidation of Sulfides Containing Pyridine Rings and Olefinic Double Bonds / Chapter 1.1. --- Introduction --- p.2 / Chapter 1.2. --- Results and Discussion --- p.5 / Chapter 1.3. --- Conclusion --- p.14 / Chapter 1.4. --- Experimental --- p.15 / Chapter 1.5. --- References --- p.32 / Chapter Part II. --- Directed Synthesis of all-Homocalix[n]arenes with Various Cavity Sizes / Chapter II. 1. --- Introduction --- p.35 / Chapter II.2. --- Previous Synthetic Routes for all-Homocalixarenes --- p.37 / Chapter II.3. --- Synthetic Plan --- p.39 / Chapter II.4. --- Results and Discussion --- p.41 / Chapter II.5. --- Conclusion --- p.55 / Chapter II.6. --- Experimental --- p.56 / Chapter II.7. --- References --- p.90 / Chapter Appendix --- 1H and 13C NMR Spectra / List of and 13C NMR Spectra of Part I --- p.92 / 1Hand 13C NMR Spectra of Part I --- p.93 / List of 1H and 13C NMR Spectra of Part II --- p.100 / 1H and 13C NMR Spectra of Part II --- p.102
5

Syntheses and studies of sapphyrins and anion receptors

Cho, Dong Gyu, 1970- 29 August 2008 (has links)
Polypyrrolic (or aromatic) macrocycles have attracted considerable recent interest due to their potential utility in various applications, including as novel materials, anion receptors, and therapeutic leads. In order to explore further the range and utility of this generalized class of molecules, various sapphyrin and sapphyrin analogues were synthesized. Among the new compounds prepared is an inverted sapphyrin, a species that displayed weak, but noticeable aromaticity. Another new system, benzoxasapphyrin was found to display a reduced anion binding affinity compared to other analogous macrocycles. Finally, several derivatized sapphyrins were prepared as potential anticancer leads. Separate from the above, efforts were made to develop anion receptors based on the indole motif. This substructure plays a key role is stabilizing a range of non-covalent interactions in complex biological structures. However, prior to the present study, indole-type hydrogen bonding donors had not been widely used to prepare synthetic anion receptors. Accordingly, a diindolyl quinoxaline system was prepared; it served to demonstrate that small molecule indole receptors can effectively bind phosphate anions in organic media. Finally, a set of cyanide anion indicators were prepared; these were predicated on the use of a cyanide-specific reaction, namely the benzil rearrangement reaction. The benzil reaction-based indicators produced in this way were found to be quite selective for the cyanide anion in organic solvents. Further, their study helped provide insights into the mechanism of this as-yet not fully studied reaction. In the context of developing this specific anion indicator, a review of other reaction-based indicators was reviewed. This is provided in Chapter 3. / text
6

New highly functionalised porphyrazines and their precursors : structure, synthesis and spectral data

Steyn, Almero Martin 27 August 2012 (has links)
M.Sc. / Porphyrazines, having similar structures to porphyrins, exhibit interesting characteristics as well as applications. These mainly stem from the highly conjugated nature of these compounds, making them useful in fields ranging from functional dyes to molecular devices to biomedical applications. Of these a highlight must be the photodynamic treatment of cancer. The usefulness of porphyrazines in these fields is very closely linked to the structure of the macrocycles. Therefore it is necessary to find methods to customise these compounds in the hopes of improving the current applications as well as broaden the horizons. There exists a gap in porphyrazine synthesis in the sense that it has not been possible before to ensure the formation of cis-porphyrazines. Therefore, the main effort in this project was directed towards addressing this void. A focus of the research was to investigate introduction of a linker between two monomer dinitrile units, used during the macrocyclisation step, to force the cis geometry into the porphyrazine. Attention was also given to finding a way to functionalise the macrocycles in such a way that the functionality could be removed at a later stage to be able to differently functionalise the porphyrazines to yield other potentially interesting structures. By manipulating existing methods to prepare porphyrazines, we were able to synthesise, with a great deal of selectivity, a cis-porphyrazine from monomers that were generally viewed as trans-directors. This represented a breakthrough in porphyrazine research. It was also possible to prepare a macrocycle with removable functionality (ally! groups) on the peripheral oxygens, thereby opening up the way towards further functionalisation. Building on this success, in which two new porphyrazines (one of which was cis functionalised) had been synthesised, it was attempted to introduce the linker unit as previously described, such that cis geometry only was possible in the macrocycle. Various reaction conditions and reaction types, ranging from Mitsunobu reactions to imine formation and reduction, were utilised in various synthetic approaches to these moieties. This effort allowed the successful synthesis of a variety of linked dinitrile dimers, which were set up to undergo Linstead macrocyclisation. However due to time constraints, these compounds have not yet been subjected to macrocyclisation but represents a challenge for the future.
7

Synthesis and characterisation of porphyrazines with chiral recognition motifs.

Mbatha, Bheki Goodson 15 May 2008 (has links)
Increased interest in porphyrazines is due to the role they play as photosensitisers in tumour therapy. A continuing problem in photodynamic therapy is selective uptake of the photosensitiser into cancerous tissue versus healthy tissue. A potential solution would be to functionalise the photosensitiser with biological molecules to assist in its selective uptake and for enhanced water solubility. The main objective of the project was the synthesis, deprotection, metalation and characterisation of peripherally carbohydrate substituted porphyrazines. A succesful synthetic pathway for the incorporation of carbohydrate moeities into porphyrazine systems in the form of 1:3, where 1 represents the carbohydrate-substituent and 3 represents the propyl-substituted pyrrole unit, has been demonstrated by this study. To this end, a range of selectively protected monosaccharide precursors was coupled to a small variety of phthalonitriles in nucleophilic aromatic substitution reactions. The products were co-macrocyclised to form hybrid porphyrazines via Linstead macrocyclisation reactions to form the desired 1:3 cyclisation products. Similarly, two protected disaccharides were synthesised de novo, coupled with the phthalonitriles and macrocyclised into their porphyrazine derivatives. Several problems were encountered in the latter set of reactions, but various methods were devised to overcome these issues. Demetalation of the porphyrazine products mentioned above was effected with relative ease using glacial acetic acid to afford the free-base pigments, which were subsequently converted into their zinc or nickel complexes. One of the problems encountered with some of the metalated products was poor solubility in spectroscopic solvents used for their characterisation. The UV-visible spectra revealed some features related to those of free-base porphyrazines or phthalocyanines but demonstrated diagnostic unsplit Q-bands confirming the success of each metalation reaction. In the second part of this investigation, some of the porphyrazines were deprotected of their isopropylidene groups of the carbohydrates to increase their hydrophilicity. This was done by using a catalytic amount of p-TsOH acid in the presence of a nucleophilic solvent. This extraction coefficients were determined as measured between 2-octanol and PBS solution. Comparison of the partition coefficients of the carbohydrate-substituted porphyrazines and their deprotected counterparts to those of non-carbohydrate substituted pigments showed that the structural alteration offers a way to significantly increase the hydrophilicity of substituted porphyrazines. Finally, photophysical studies on the porphyrazine products were performed, and these include singlet oxygen generation, triplet lifetimes and -yields, etc. The results of this part of study showed that the products are good candidates for PDT and that the nature of the carbohydrate played an insignificant role in the activity of the pigments. Rather, the position of attachment and the presence/absence of a metal in the core cavity were found to be more important. / Prof. D.B.G. Williams
8

Synthesis and characterization of b-substituted porphyrins and their metal complexes: Monomer, Dimer and coordination polymer.

January 1996 (has links)
by Xiang Zhou. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references. / Acknowledgment --- p.i / Abstract --- p.ii / Abbreviations --- p.iii / Table of Contents --- p.iv-v / Chapter Chapter I --- Synthesis of β-substituted porphyrins --- p.1 / Chapter I-1 --- Introduction --- p.1 / Chapter I-1-1 --- Activation of alkanes: the biomimetic approach --- p.2 / Chapter I-1-2 --- Electronic effects in β-substituted porphyrins --- p.5 / Chapter I-1-3 --- Synthetic approach to β-substituted porphyrins --- p.7 / Chapter I-2 --- Results and discussions --- p.14 / Chapter I-2-1 --- Bromination of porphyrins at β-positions --- p.14 / Chapter I-2-2 --- Synthesis of boronic acids --- p.17 / Chapter I-2-3 --- Synthesis of β-substituted porphyrins --- p.18 / Chapter I-2-4 --- Uv spectra --- p.25 / Chapter I-2-5 --- "Crystal structures of H2TPP(Ph)4, H2TPP(Me)4, H2TPP(Tol)8 and H2TMP(Ph)8" --- p.26 / Chapter I-3 --- Conclusion --- p.43 / Chapter I-4 --- Experimental section --- p.44 / Chapter I-5 --- References --- p.58 / Chapter Chapter II --- Synthesis and Properties of Diporphyrins --- p.63 / Chapter II-1 --- Introduction --- p.63 / Chapter II-1-1 --- Linear dimers --- p.64 / Chapter II-1-2 --- Cofacial porphyrins (or strati-bisporphyrins) --- p.68 / Chapter II-1-3 --- Synthetic approach --- p.71 / Chapter II-2 --- Results and discussions --- p.73 / Chapter II-2-1 --- Synthetic strategy --- p.73 / Chapter II-2-2 --- Synthesis of diporphyrins via condensation and Suzuki cross- coupling --- p.75 / Chapter II-2-3 --- Synthesis of diporphyrins via Suzuki cross-coupling and condensation --- p.75 / Chapter II-2-4 --- Metalation of diporphyrins --- p.78 / Chapter II-2-5 --- Spectroscopy --- p.81 / Chapter II-3 --- Conclusion --- p.89 / Chapter II-4 --- Experimental section --- p.90 / Chapter II-5 --- Reference --- p.100 / Chapter Chapter III --- Novel Rhodium Porphyrin Complexes: Intermolecular Activation of Arene Carbon-Hydrogen Bond and Formation of a Nitrile-Bridged Coordination Polymer --- p.104 / Chapter III-l --- Introduction --- p.104 / Chapter III-1-1 --- Activation of C-H bonds --- p.104 / Chapter III-1-2 --- Activation of C-H bond by rhodium porphyrin complexs --- p.106 / Chapter III-2 --- Results and discussions --- p.108 / Chapter III-2-1 --- Synthesis of rhodium porphyrin complexes --- p.108 / Chapter III-2-2 --- Proton NMR --- p.112 / Chapter III-2-3 --- UV and binding studies of rhodium porphyrin complexes --- p.115 / Chapter III-2-4 --- IR spectra --- p.117 / Chapter III-2-5 --- Crystal structures of rhodium porphyrin complexes --- p.118 / Chapter III-3 --- Conclusion --- p.148 / Chapter III-4 --- Experimental section --- p.149 / Chapter III-5 --- References --- p.154 / Appendix --- p.157 / NMR Spectra --- p.159
9

Part I, synthesis, spectroscopic properties and aggregation behavior of substituted 2,3-naphthalocyanines: and, Part II, synthetic studies of substituted dicyano-anthracenes and tetracens(sic). / Synthesis, spectroscopic properties and aggregation behavior of substituted 2,3-naphthalocyanines / Part II, synthetic studies of substituted dicyano-anthracenes and tetracens / Synthetic studies of substituted dicyano-anthracenes and tetracens

January 1999 (has links)
by Michael Tsang Ming Choi. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 85-90). / Abstracts in English and Chinese. / ACKNOWLEDGMENT --- p.i / TABLE OF CONTENTS --- p.ii / LIST OF FIGURES --- p.iv / LIST OF TABLES --- p.vi / ABBREVIATIONS --- p.vii / ABSTRACT --- p.viii / 摘要 --- p.ix / Chapter PART I. --- "SYNTHESIS, SPECTROSCOPIC PROPERTIES AND AGGREGATION BEHAVIOR OF SUBSTITUTED 2,3- NAPHTHALOCYANINES" / Chapter 1 --- INTRODUCTION --- p.2 / Chapter 1.1 --- "Synthesis of 2,3 -Naphthalocyanines" --- p.6 / Chapter 1.2 --- Aggregation Phenomena of Phthalocyanines --- p.14 / Chapter 1.3 --- Phthalocyanines with Crown Ether Voids --- p.20 / Chapter 2 --- RESULTS AND DISCUSSION --- p.26 / Chapter 2.1 --- "Synthesis of Substituted 2,3-Naphthalocyanines" --- p.26 / Chapter 2.2 --- Synthesis of Substituted Phthalocyanines --- p.29 / Chapter 2.3 --- "Characterization of 2,3-Naphthalocyanines and Phthalocyanines" --- p.31 / Chapter 2.4 --- "Aggregation Behavior of Octasubstituted 2,3-Naphthalocyanines and Phthalocyanines" --- p.34 / Chapter 2.5 --- Liquid Crystalline Properties of64 --- p.43 / Chapter 2.6 --- "Synthesis of a Crown Ether-Substituted 2,3-Naphthalocyanine" --- p.45 / Chapter 2.7 --- Conclusion --- p.48 / Chapter 3 --- EXPERIMENTAL SECTION --- p.49 / Chapter 3.1 --- Materials --- p.49 / Chapter 3.2 --- Physical Measurements --- p.49 / Chapter 3.3 --- General Procedure for the Preparation of Dinitriles --- p.50 / Chapter 3.4 --- General Procedure for the Cyclization of Dinitriles --- p.53 / Chapter PART II. --- SYNTHETIC STUDIES OF SUBSTITUTED DICYANO-ANTHRACENES AND TETRACENES / Chapter 1 --- INTRODUCTION --- p.57 / Chapter 2 --- RESULTS AND DISCUSSION --- p.63 / Chapter 2.1 --- Synthesis of Substituted Anthracenes --- p.63 / Chapter 2.2 --- Synthesis of Substituted Tetracenes --- p.72 / Chapter 2.3 --- Conclusion --- p.77 / Chapter 3 --- EXPERIMENTAL SECTION --- p.78 / REFERENCES --- p.85 / Chapter APPENDIX --- Crystallographic data of dimer of anthracene118 --- p.91
10

Molecular engineering of N-heteroacenes and macrocyclic arenes: design, synthesis and properties. / 氮雜並萃和共軛芳烴大環的分子工程: 設計, 合成和性質研究 / CUHK electronic theses & dissertations collection / Dan za bing cui he gong e fang jing da huan de fen zi gong cheng: she ji, he cheng he xing zhi yan jiu

January 2013 (has links)
He, Zikai. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

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