by Raymond Chi-Yuen Kwong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 60-62). / Acknowledgements --- p.i / Abbreviations --- p.ii / Abstract --- p.iii / Chapter 1. --- Introduction --- p.1 / Chapter 2. --- Synthetic Methodology for Arylenevinylenes --- p.12 / Chapter 3. --- Result and Discussion --- p.15 / Chapter 4. --- Conclusion --- p.42 / Chapter 5. --- Experimental --- p.43 / Chapter 6. --- References --- p.60 / Chapter 7. --- Spectra

by Marco Ming Yeung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1997. / Includes bibliographical references (leaves 90-96). / ACKNOWLEDGMENTS --- p.i / ABSTRACT --- p.ii / CONTENTS --- p.iii / LIST OF FIGURES --- p.v / LIST OF TABLES --- p.vi / ABBREVIATIONS --- p.vii / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1. --- Theoretical Background of Nonlinear Optics --- p.1 / Chapter 1.2. --- Organic Nonlinear Optical Chromophores --- p.5 / Chapter 1.3. --- Porphyrins as Nonlinear Optical Chromophores --- p.8 / Chapter 1.4. --- Synthetic Aspects of Porphyrins --- p.16 / Chapter 1.4.1. --- Porphyrin Substrates --- p.16 / Chapter 1.4.2. --- Vilsmeier Formylation --- p.17 / Chapter 1.4.3. --- Bromination --- p.21 / Chapter 1.4.4. --- Knoevenagel Condensation --- p.24 / Chapter 1.4.5. --- Palladium-mediated Cross-coupling --- p.25 / Chapter 2. --- RESULTS AND DISCUSSION --- p.28 / Chapter 2.1. --- "Preparation of 5,15-Diphenylporphyrinatonickel(II)" --- p.28 / Chapter 2.2. --- "Vilsmeier Formylation of 5,15-Diphenylporphyrinatonickel(II)" --- p.30 / Chapter 2.3. --- Preparation of Push-pull Porphyrins --- p.47 / Chapter 2.4. --- Molecular Structures of 65 and76 --- p.59 / Chapter 2.5. --- Nonlinear Optical Properties of Push-pull Porphyrins 65 and66 --- p.63 / Chapter 2.6. --- Attempted Syntheses of Push-pull Porphyrin Trimer and Dimer --- p.65 / Chapter 2.7. --- Conclusion --- p.69 / Chapter 3. --- EXPERIMENTAL SECTION --- p.70 / Chapter 3.1. --- General Methods --- p.70 / Chapter 3.2. --- Physical Measurements --- p.70 / Chapter 3.3. --- Preparation of Push-pull Porphyrins --- p.71 / Chapter 3.4. --- Attempted Preparation of Push-pull Porphyrin Trimer and Dimer --- p.86 / Chapter 4. --- REFERENCES --- p.90 / APPENDIX A 1 H NMR Spectra of Porphyrins --- p.97 / APPENDIX B Crystal Data for 65 and 76 --- p.115 / APPENDIX C Computed Geometry of 65 and 66 from Semiempirical PM3(tm) Calculations --- p.131

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Thesis (Ph. D.)--Columbia University, 1934. / Vita. Bibliography: p. 26.

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A group of azabiphenyl complexes and supramolecules, and their reduced and oxidized forms when possible, were characterized by cyclic voltammetry and electronic absorption spectroscopy. The oxidized and reduced species, if sufficiently stable, were further generated electrochemically inside a specially designed quartz cell with optically transparent electrode, so that the spectra of the electrochemically generated species could be taken in situ. Assignments were proposed for both parent and product electronic spectra. Species investigated included a range of Ru(II) and Pt(II) complexes, as well as catenanes and their comparents. Using the localized electronic model, the electrochemical reduction can be in most cases assigned as azabiphenyl-based, and the oxidation as transition metal-based. This is consistent with the fact that the azabiphenyl compounds have a low lying π* orbital. The electronic absorption spectra of the compounds under study are mainly composed of π —> π* bands with, in some cases, charge transfer bands also.

Two bis-imidazol-2-ylidine N-heterocyclic carbenes have been employed as ancillary ligands in an attempt to illustrate their utility in the palladium-mediated preparation of aryl ethers from aryl halides. Ullman-type homo-coupling of the aryl halides persistently occurred instead of ether formation. One of the well known N-heterocyclic carbenes, IPr, was employed with the same results. A variety of reaction conditions and reagents were investigated including solvents, N-heterocyclic carbene species, palladium source, alkoxide base, palladium to ligand ratio and reaction time. Reactivity of the individual N-heterocyclic carbenes as ancillary ligands in the palladium-catalyzed amination reaction of aryl halides was investigated to determine functionality of the carbenes. Alternative procedures to prepare the key intermediates in the synthesis of the bisimidazol- 2-ylidines were developed. In this study the aryl imidazoles were prepared from the corresponding phenol and carbonyldiimidazole. Subsequent N-alkylation then furnished the Nheterocyclic carbenes in high yield. Novel unsymmetrical N-heterocyclic carbenes with aryl and benzylic side groups have been synthesized as models for the subsequent synthesis of unsymmetrical polymer-bound Nheterocyclic carbenes. The unsymmetrical ligands were employed in the palladium-catalyzed amination of aryl halides and in the Suzuki-Miyaura Reaction. Two Merrifield resin polymerbound N-heterocyclic carbene ligands were then synthesized and employed in the aryl amination and Suzuki-Miyaura Reactions. Both reactions were greatly accelerated by the implementation of microwave heating. The Merrifield resin polymer-bound palladium-ligand complexes have been recycled through several reactions without loss of activity.