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Chan Wing Kin. / Thesis submitted in: Oct 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Abstracts in English and Chinese. / Abstract --- p.i / Abstract (in Chinese) --- p.iii / Acknowledgement --- p.iv / Table of Contents --- p.vi / List of Figures --- p.xi / List of Tables --- p.xv / List of Schemes --- p.xvi / Abbreviations --- p.xviii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- General Background of Phthalocyanines --- p.1 / Chapter 1.2 --- General Background of Liquid Crystals --- p.3 / Chapter 1.3 --- Structural Classification of the Mesophases --- p.6 / Chapter 1.3.1 --- The Columnar Liquid Crystals --- p.6 / Chapter 1.3.2 --- The Nematic Phase --- p.10 / Chapter 1.3.3 --- The Lamellar Phase --- p.11 / Chapter 1.4 --- Applications of Columnar Discotic Liquid Crystals --- p.13 / Chapter 1.4.1 --- General Properties of HATn Materials and Phthalocyanines --- p.13 / Chapter 1.4.2 --- Supramolecular Channels and Wires --- p.16 / Chapter 1.4.3 --- Phthalocyanine Based Gas Sensors --- p.21 / Chapter 1.5 --- General Synthesis of Liquid Crystalline Phthalocyanines --- p.23 / Chapter 1.5.1 --- Peripherally Substituted Phthalocyanines --- p.23 / Chapter 1.5.1.1 --- Octakis(alkoxymethy l)phthalocy anines --- p.23 / Chapter 1.5.1.2 --- Octa-alkoxyphthalocyanines --- p.26 / Chapter 1.5.1.3 --- Octa-alkylphthalocyanines --- p.29 / Chapter 1.5.1.4 --- Octakis-(alkoxycarbonyl)phthalocyanines --- p.30 / Chapter 1.5.1.5 --- Octa-(p-alkoxylphenyl)phthalocyanines --- p.32 / Chapter 1.5.1.6 --- Tetrakis[oligo(ethyleneoxy)] phthalocyanines --- p.34 / Chapter 1.5.2 --- Non-Peripherally Substituted Phthalocyanines --- p.35 / Chapter 1.5.2.1 --- Octa(alkoxymethyl)phthalocyanines --- p.35 / Chapter 1.5.2.2 --- Octa-alkylphthalocyanines --- p.37 / Chapter 1.5.3 --- Unsymmetrically Substituted Phthalocyanines --- p.40 / Chapter 1.5.4 --- Liquid Crystalline Metallophthalocyanines --- p.42 / Chapter 1.5.4.1 --- Copper Phthalocyanines --- p.42 / Chapter 1.5.4.2 --- "Manganese, Cobalt, Nickel, and Zinc Phthalocyanines" --- p.43 / Chapter 1.5.4.3 --- Lutetium Phthalocyanines --- p.43 / Chapter 1.5.4.4 --- "Silicon, Tin, and Lead Phthalocyanines" --- p.44 / Chapter 1.6 --- Summary --- p.45 / Chapter 1.7 --- References --- p.47 / Chapter Chapter 2 --- "Syntheses, Aggregation Behavior and Liquid Crystalline Properties of Peripherially Octaalkynyl Phthalocyanines" --- p.57 / Chapter 2.1 --- Synthesis and Characterization of Octaalkynyl Phthalocyanines --- p.57 / Chapter 2.1.1 --- Preparation of Alkynyl Fragment 22 --- p.57 / Chapter 2.1.2 --- Preparation of Alkynyl Phthalonitrile 23 --- p.58 / Chapter 2.1.3 --- "Synthesis and Characterization of [2,3,9,10,16,17,23,24-Octakis(3,4,5-tris (dodecyloxy)phenylethynyl)phthalocyaninato]magnesium(II) (29)" --- p.62 / Chapter 2.2 --- Electronic Absorption of Alkynylated Phthalocyanine 29 --- p.65 / Chapter 2.3 --- Liquid Crystalline Properties of Alkynyl Phthalocyanine 29 --- p.71 / Chapter 2.4 --- Summary --- p.73 / Chapter 2.5 --- Experimental Section --- p.74 / Chapter 2.5.1 --- General Information --- p.74 / Chapter 2.5.2 --- Physical Measurements --- p.74 / Chapter 2.5.3 --- Photophysical Measurements --- p.75 / Chapter 2.5.4 --- Experimental Procedure --- p.76 / Chapter 2.6 --- References --- p.83 / Chapter Chapter 3 --- Facile Synthesis of Liquid Crystalline Phthalocyanines Through Transesterification Reactions --- p.86 / Chapter 3.1 --- Synthesis and Characterization --- p.86 / Chapter 3.1.1 --- "Preparation of 4,5-bis(4-methoxycarbonylphenoxy)phthalonitrile (30)" --- p.86 / Chapter 3.1.2 --- Preparation of Phthalocyanines --- p.87 / Chapter 3.2 --- Electronic Absorption Properties and Aggregation Behavior --- p.91 / Chapter 3.3 --- Liquid Crystalline Properties of Phthalocyanines 31 -37 --- p.101 / Chapter 3.4 --- Summary --- p.104 / Chapter 3.5 --- Experimental Section --- p.105 / Chapter 3.5.1 --- Experimental Procedure --- p.105 / Chapter 3.6 --- References --- p.114 / Chapter Chapter 4 --- "In vitro Photodynamic Activities of Peripherially Octa-substituted Zinc Phthalocyanines with Terminal Mono-, Di- and Triethylene Glycol Chains" --- p.115 / Chapter 4.1 --- Photodynamic Therapy (PDT) --- p.115 / Chapter 4.1.1 --- Brief Introduction of Photodynamic Therapy --- p.115 / Chapter 4.1.2 --- Photophysical Mechanism Involved in PDT --- p.117 / Chapter 4.2 --- Photophysical Properties of Phthalocyanines 34-36 --- p.119 / Chapter 4.2.1 --- An overview of photochemical and photophysical processes --- p.119 / Chapter 4.2.2 --- Spectroscopic and Photophysical Properties of Phthalocyanines 34-36 --- p.122 / Chapter 4.3 --- In vitro Photodynamic Activities --- p.128 / Chapter 4.4 --- Summary --- p.128 / Chapter 4.5 --- Experimental Section --- p.129 / Chapter 4.5.1 --- In vitro Studies --- p.129 / Chapter 4.6 --- References --- p.131 / Appendix --- p.135

Chapter 1 presents an overview of the synthetic methods and properties of phthalocyanines, focusing on the unsymmetrical analogues, side-strapped derivatives, and crown ether-containing phthalocyanines. The use of these compounds in photodynamic therapy and their supramolecular chemistry are also reviewed. / Chapter 2 reports the synthesis of a series of unsymmetrical "3+1" zinc(II) phthalocyanines via a one-pot cyclization-transesterification procedure in different alcoholic solvents. Their photophysical properties and in vitro photodynamic activities toward HT29 human colorectal adenocarcinoma cells and HepG2 human hepatocarcinoma cells are also reported. One of the compounds, a zinc(II) phthalocyanine substituted with two polyethylene glycol chains, can form surfactant-free nanoparticles in water and in the culture media. These phthalocyanine-containing nanoparticles exhibit a high photocytotoxicity toward HepG2 cells showing that the polymeric substituents may serve as an effective carrier system. / Chapter 4 reports the synthesis and spectroscopic properties of a side-strapped bis(17-crown-5)-containing zinc(II) phthalocyanine. In contrast to the previously reported benzo-fused crown ether-appended phthalocyanines, the ether rings of this molecule are orthogonal to the phthalocyanine plane. As a result, this compound forms J-aggregate in chloroform. Upon addition of alkali metal ions, these aggregates are disrupted forming a linear supramolecular structure, which has been inferred by absorption and fluorescence spectroscopic methods. / Chapter 5 describes the synthesis and spectroscopic properties of two side-strapped zinc(II) phthalocyanines, which have one and two benzo-25-crown-8 moieties, respectively. The bis(crown ether) analogue favors the formation of J-aggregate in non-coordinating solvents. In CHCl 3, the aggregation of these compounds is promoted by the addition of 1,2-bis(pyridinium)ethane bis(hexfluorophosphate). The aggregation of these compounds can also be induced by the oxonium ions generated by the addition of organic acids such as trifluoroacetic acid and acetic acid. After neutralization with Et3N, the aggregate is disrupted and the phthalocyanines are converted back to their original nonaggregated state. For the symmetrically substituted compound, this acid-base switched aggregation-disaggregation process can be recycled for more than 8 times. / The synthesis, spectroscopic characterization, photophysical properties, aggregation properties, and in vitro photodynamic activities of several side-strapped phthalocyanines are described in Chapter 3. Pentaerythritol, having four hydroxyl groups, has been used as the linker to connect hydrophilic oligoethylene glycol chains or hydrophobic alkyl chains to the phthalocyanine core. The aggregation tendency of these compounds, which depends on their amphiphility, has been studied by absorption spectroscopy. The relationship of this property with the in vitro photocytotoxicity has also been revealed. / This thesis reports our studies on several novel series of phthalocyanines including a series of "3+1" unsymmetrical phthalocyanines formed by a one-pot cyclization-transesterification procedure, and several side-strapped phthalocyanines having an amphiphilic character or containing crown ether units. The applications of these compounds in photodynamic therapy and supramolecular chemistry have also been explored. / by Bai, Ming. / "September 2007." / Source: Dissertation Abstracts International, Volume: 69-08, Section: B, page: 4745. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.

A novel series of silicon(IV) phthalocyanines substituted axially with one or two 1,3-bis(dimethylamino)-2-propoxy group(s) are described in Chapter 3. These compounds are essentially non-aggregated in common organic solvents and show a weak fluorescence emission, while their methylated derivatives are also non-aggregated even in aqueous media and exhibit a strong fluorescence emission. The photocytotoxicities of these compounds against HepG2 and J774 cells have also been investigated. These new phthalocyanines, in particular the unsymmetrical and amphiphilic analogues, are highly potent with IC50 values down to 20 nM. The cellular uptake and subcellular localisation of these compounds have also been studied by fluorescence microscopy. The unsymmetric phthalocyanine SiPc[OC3H5(NMe2 )2](OMe) has a high and selective affinity to the mitochondria of HepG2 cells. / Chapter 1 presents an overview of photodynamic therapy, including its historical development, current clinical status, and photophysical and biological mechanisms. Some representative photosensitisers are also reviewed. / Chapter 2 describes two silicon(IV) phthalocyanines containing poly(ethylene glycol) chains at the axial positions, including their synthesis, spectroscopic characteristics and photophysical properties. Their complexation with bovine serum albumin and in vitro photodynamic activities towards HepG2 human hepatocarcinoma cells and J774 mouse macrophage are also reported. / Chapter 4 discusses the photodynamic effects of a series of silicon(IV) phthalocyanines with different axial substituents against HT29 and T84 human colon adenocarcinoma cells, with the long-term goal of developing efficient photosensitising agents for colorectal cancer. While these compounds are not cytotoxic in the absence of light, they exhibit high photocytotoxicities with IC50 values as low as 17 nM. / Chapter 5 reports the synthesis and characterisation of a series of halogenated silicon(IV) phthalocyanines substituted axially with poly(ethylene glycol), 1,3-bis(dimethylamino)-2-propoxy or isopropylidene-protected galactose groups, with the goal of enhancing the photosensitising properties by heavy atom effect. (Abstract shortened by UMI.) / This thesis describes the synthesis, spectroscopic characterisation, and photo-physical and biological properties of a series of novel silicon(IV) phthalocyanines which are potentially useful as second-generation photosensitisers for photodynamic therapy. / Lo Pui-chi. / "September 2005." / Adviser: Dennis K. P. Ng. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3813. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

本论文主要研究了各种可见光光催化剂的合成。包括了Cu₂S，CuO/ZnO复合物以及钒酸根掺杂的磷酸银材料。论文讨论了这些光催化剂的性质与光催化活性，机理同应用也在本文中进行了探讨。 / 首先，发现并合成了硫化亚铜十四面体纳米粒子。研究中发现三正辛基膦对硫化亚铜多面体的形成是必需的。得到的硫化亚铜多面体具有暴露的罕见的面。通过对其光电活性的研究发现，相对于常见的硫化亚铜六边形片状纳米粒子，这种多面体具有5倍以上的活性。 / 其次，异质结构的CuO/ZnO复合材料通过光化学沉积合成。在这两种半导体的接触面形成了p-n结，促进了电子在两者间的传递。在荧光谱图中发现，因电子空穴淬灭引发的荧光峰消失了。这代表由于异质节的形成电荷分离的效率大大提高，从而光催化的效率也得到了很好的提高。 / 最后，含氧根离子作为一种新型的掺杂材料被用于提高磷酸银的性质。磷酸银光解水的能力经过掺杂后得到了显著提高。同时，其在可见光下的稳定性也获得了很大的提高。含氧根离子掺杂物对于磷酸银材料的性质改变及机理在文中都进行了探讨。 / This thesis focuses primarily on the development of visible-light-driven photocatalysts. These include Cu₂S, CuO/ZnO composites and vanadate doped Ag₃PO₄. The property and activity of the materials were studied. The application and mechanism of the enhancement were also explored. / Firstly, 14-facet polyhedra Chalcocite Cu₂S Nanocrystals were synthesized utilizing solvothermal method. It was found that the presence of trio-n-octylphosphine was essential for the exposure of unconventional faces. Studies of the photoelectrochemical performance have indicated that the polyhedra bounded by facets exhibit much higher activities than Cu₂S hexagonal plates with only facets. / Secondly, a heterostructure of CuO/ZnO was fabricated via photochemical deposition. The formation of p-n junction improved the visible light absorption property of ZnO. Photoluminescence spectra showed diminished peaks caused by recombination of excited electrons and holes in the semiconductor which demonstrated that the heterostructure facilitated the charge separation and thus enhanced the photocatalytic activity. / Thirdly, an oxoanion doping method was employed to improve the properties of Ag₃PO₄. The water oxidation ability was found to be higher than the pure Ag₃PO₄. The doping method was proven to be effective in both improving activity and durability. The mechanism of the doping method was also discussed. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Li, Yecheng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 71-77). / Abstracts also in Chinese. / Abstract (Chinese) --- p.i / Abstract --- p.ii / Acknowledgement --- p.iii / List of Figures --- p.v / Table of Contents --- p.viii / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1. --- Basic Principles of Photocatalysis --- p.1 / Chapter 1.2. --- Strategies to Develop Visible-light-driven Photocatalysts --- p.4 / Chapter 1.2.1. --- Native visible-light-driven photocatalysts --- p.4 / Chapter 1.2.2. --- Ion substitution (doping) --- p.6 / Chapter 1.2.3. --- Solid solution photocatalysts --- p.10 / Chapter 1.2.4. --- Dye sensitization to harvest visible light --- p.13 / Chapter 1.3. --- Strategies to Enhance Photocatalytic Activity --- p.15 / Chapter 1.3.1. --- Interface engineering --- p.15 / Chapter 1.3.2. --- Band gap engineering (Tuning distribution of dopants) --- p.17 / Chapter 1.3.3. --- Crystal structure and morphology engineering --- p.19 / Chapter 1.3.4. --- Cocatalyst loading --- p.23 / Chapter 1.4. --- Summary --- p.25 / Chapter 1.5. --- Objective of the Thesis --- p.25 / Chapter Chapter 2 --- Facet Effect of Copper(I) Sulfide Nanocrystals on Photoelectrochemical Properties --- p.28 / Chapter 2.1. --- Introduction --- p.28 / Chapter 2.2. --- Experimental --- p.30 / Chapter 2.2.1. --- Synthesis --- p.30 / Chapter 2.2.2. --- Characterization --- p.30 / Chapter 2.2.3. --- Photoelectrochemical performance analysis --- p.31 / Chapter 2.3. --- Results and Discussion --- p.32 / Chapter 2.4. --- Conclusions --- p.40 / Chapter Chapter 3 --- CuO-ZnO Composites for Enhanced Photoelectrochemical Performance --- p.41 / Chapter 3.1. --- Introduction --- p.41 / Chapter 3.2. --- Experimental --- p.42 / Chapter 3.2.1. --- Synthesis --- p.42 / Chapter 3.2.2. --- Characterization --- p.43 / Chapter 3.2.3. --- Photoelectrochemical performance analysis --- p.44 / Chapter 3.3. --- Results and Discussion --- p.45 / Chapter 3.4. --- Conclusions --- p.56 / Chapter Chapter 4 --- Vanadate Doped Ag₃PO₄ and Its Enhanced Photoactivity and Durability --- p.57 / Chapter 4.1. --- Introduction --- p.57 / Chapter 4.2. --- Experimental --- p.59 / Chapter 4.2.1. --- Synthesis --- p.59 / Chapter 4.2.2. --- Characterization --- p.59 / Chapter 4.2.3. --- Oxygen evolution tests --- p.60 / Chapter 4.3. --- Results and Discussion --- p.61 / Chapter 4.4. --- Conclusions --- p.68 / Chapter Chapter 5 --- Summary --- p.69 / Reference --- p.71

Transfer hydrogenation has been recognized to be an important synthetic method in both academic and industrial research to obtain valuable products including alcohols. Transition metal catalysts based on precious metals, such as Ru, Rh and Ir, are typically employed for this process. This thesis starts with a study on the potential of an Fe based complex carrying a PNP ligand (2,6-{Ph2PNH}2(NC5H3)) to function as an active transfer hydrogenation catalyst for the conversion of ketones to alcohols. During the analysis of the performance parameters of this potential catalyst, it was discovered that the added base, KOtBu, was the actual catalyst. Other bases were explored as catalysts for this transformation as well as the general performance features of this simple alkali metal base. In a separate project described in Chapter 3, the search for catalysts shifted focus to a study of the potential of a series of first row transition metal-based complexes supported by a bis(thioether)pyridine “SNS” ligand for photocatalytic hydrogen production. This initial study led to the observation that the Fe complex [Fe(k3-2,6-(CH3SCH2)2C5H3N)Br2]2 was a capable photocatalyst for H2 production in combination with a photosensitizer (Ru(bpy)3)2+) and an electron donor (triethanolamine). Although water was initially believed to be the source of protons that were reduced to H2, analysis of control experiments pointed to the hydrogen source being the electron donor.

Thesis (Ph. D.)--Oregon Graduate Center, 1980.

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references.

Ph.D. / Inorganic Chemistry / Copper (I) forms π complexes with olefin-containing metal complexes in aqueous solution. Reduction of a series of pyridinepentaammineruthenium (III) ions, where L is a pyridine or 4-substituted pyridines, was studied. For the (NH[subscript 3]) [subscript 5] Ru (III)-4-viny1pyridine ion it is possible to measure separately preequilibrium binuclear ion formation and electron transfer. The electron transfer pathway is determined to be intramolecular from comparison with rate behavior of (NH[subscript 3]) [subscript 5] (III)-4-ethylpyridine, Cu (I) and (NH[subscript 3]) [subscript 5] (III)-pyridine, Cu (I) redox pairs. Rate parameters are also determined for the reverse reaction. Cu (II) catalyzed autoxidation of the (NH[subscript 3]) [subscript 5] (II) - 4-vinylpyridine ion. The redox equilibrium constant determined from the kinetic data agrees reasonably with that calculated from the redox potentials of the reactants. Qualitative models have been advanced from which it is suggested that the entropy of activation gives a measure of the probability for electron transfer in the activated complex, values near zero indicating that electron-tunneling is not rate-limiting. Cu(I)-olefin containing binuclear ions of (NH[subscript 3])[subscript 5]Co(III)L, where L is an alkylpyridine or alkylamine, undergo efficient intramolecular electron transfer when irradiated in the Cu(I)-olefin(n*) absorption band. The results of photoredox studies of a series of alkylamine and alkylpyridine containing binuclear ions are reported. The quantum yields for Co (II) production is shown to falloff monotonically for increasing number of methylene carbons in the chain. Binuclear ions containing polyisoprenyl bridging ligands were also investigated. Mixed solvent studies show decreased quantum yield with increasing ethanol content of the aqueous media. Medium and chain configuration effects are discussed.

This thesis describes the study of a variety of nanoscale materials and the development of novel synthetic strategies for their production. While the focus and bulk of this study have been directed specifically at subwavelength lithography, a significant portion of this thesis research involves nanoparticle synthesis, characterization, and functionalization. Put in very simple terms, optical lithography is a process where a beam of light, focused in a specific pattern, is used to generate a physical pattern on a solid substrate. This technology forms the basis for almost all microchip production in the world at the present time. As demand for faster and more powerful chips increases, the need to further miniaturize the patterns while minimizing cost has become very important. Multiple photochemical systems were developed in the search for non-reciprocal photochemistry at 193 nm to increase the resolution of lithographic processes at that wavelength. One approach, based on anthracene sensitization of sulfonium salts for acid generation, used photochemically reversible 4+4 aromatic cycloaddition reactions to introduce the non-linear photochemistry. A second approach took advantage of the photochemistry of N-methylphenothiazine and provided the first true example of a lithographically-relevant multi-photon acid generating process. Since all of the systems we studied used sulfonium salts as the acid generating species, we also looked at the photochemistry of the salts themselves. We evaluated the structural effects of the salts on their direct photochemistry and the implications for sensitized multi-photon photochemistry. We found that the identity of the anion plays a significant role in both processes and propose a new photochemical mechanism for acid generation that involves a charge transfer excitation process. We also describe the synthesis and characterization of novel fluorescent silver nanoparticles, both in solution and polymer films. We show that the fluorescent images can be patterned easily and preliminary results show that photolithography based on nanoparticle formation may be possible. This latter approach could provide a facile route to nanoparticle-embedded functional materials. This work with nanoparticles was inspired partly by earlier work, also presented herein, on semiconductor nanoparticles and their interactions with disulfide ligands.