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The affinity of hemoglobin for CO relative to O₂ is decreased compared to simple iron-porphyrin systems mainly due to electronic effects. Hydrogen-bond formation with the His E7 residue of hemoglobin has been revealed to stabilize the bound dioxygen. This thesis describes the development of a series porphyrin models, benzene-4/4 (49a), benzene-5/5 (49b), amidobenzene-4/4 (49c) and amidobenzene-5/5 (49d) capped porphyrins, which serve as simple models to imitate the hydrogen bonding in hemoglobin. The chain linked bis pyrroles 38 were synthesized by Friedel-Crafts acylation of the benzene and nitrobenzene diacid chain derivatives with two equivalents of the β-unsubstituted pyrrole 36, followed by diborane reduction of the ketonic groups. After the nitro functions were transformed to the acetamides, modification of the ethyl ester functions of 38a, 38b and 39 via the benzylesters 40, the carboxypyrroles 41 and the α-unsubstituted pyrroles 42 afforded the important bis formyl pyrroles 43. The cyanoacrylate protected formyl pyrrole derivatives 44 were subjected to monochlorination at the α-methyl groups followed by condensation with two equivalents of the α-unsubstituted pyrrole 46 to give dipyrromethane dimers 47. Strong aqueous alkali caused saponification of the two ester groups and deprotection of the formyl functions to give 48. The α formyl-α′-unsubstituted dipyrromethane dimer, resulting from the thermal decarboxylation of 48, was cyclized to produce the porphyrin 49 in acidic medium. The interactions of CO and O₂ with the heme derivatives, Fe[superscript]Ⅱ(porphyrin)(DcIm), have been studied. The CO binding constant of the amide substituted heme is two foldlarger than that of the non-amide substituted heme. In contrast, the low temperature (-45°C) O₂ binding constants of the hemes have shown a 6-8 fold increase from nonamide to amide substituted hemes, probably because of a hydrogen bonding between the amide function and bound dioxygen similar to the hydrogen bonding in hemoglobin. [formula omitted] / Science, Faculty of / Chemistry, Department of / Graduate

by Man Kin Tse. / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

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本論文主要研究了鹼性添加劑促進二價鈷卟啉絡合物(Co{U+1D35}{U+1D35}(por))在苯溶劑中與溴代苯及其衍生物(ArX)的反應及鹼性條件下，該絡合物催化溴代苯及其衍生物的脫鹵反應。 / 第一部分主要介紹了在KOH和{U+1D57}BuOH存在下，Co{U+1D35}{U+1D35}(por)斷裂碳-溴鍵（Ar-Br）形成各種三價鈷卟啉芳基絡合物（Co{U+1D35}{U+1D35}{U+1D35}(por)Ar）(eq. 1)。 / 機理研究顯示，Co{U+1D35}{U+1D35}(por)首先從ArBr中得到Br·形成芳基自由基（Ar·）及Co{U+1D35}{U+1D35}{U+1D35}(por)Br (Scheme 1, i). Ar 與另一個Co{U+1D35}{U+1D35}(por)反應得到Co{U+1D35}{U+1D35}{U+1D35}(por)Ar (Scheme 1, ii)。在鹼性條件中，Co{U+1D35}{U+1D35}{U+1D35}(por)Br 最終形成CoII(por)從而繼續反應 (Scheme 1, iii-iv)。 / 第二部份主要介紹了在200 ºC時， 鹼性條件下Co{U+1D35}{U+1D35}(por)催化鹵代苯及其衍生物脫鹵形成對應芳烴的反應 (eq. 2)。 該反應在四氫呋喃（THF）及異丙醇 ({U+2071}PrOH) 中都可以進行。 / 機理研究顯示， Co{U+1D35}{U+1D35}(ttp) 首先與ArBr反應得到Ar· 和Co{U+1D35}{U+1D35}{U+1D35}(ttp)Br (Scheme 2, i)。 Ar 從溶劑（THF 或者 {U+2071}PrOH）得到一個氫原子從而形成芳烴 (ArH) (Scheme 2, ii)。 Ar 也可以與另一個Co{U+1D35}{U+1D35}(ttp) 反應得到Co{U+1D35}{U+1D35}{U+1D35}(ttp)Ar。 在鹼性條件下， Co{U+1D35}{U+1D35}{U+1D35}(ttp)Ar水解形成ArH 和 Co{U+1D35}{U+1D35}{U+1D35}(ttp)OH (Scheme 2, iii)。 Co{U+1D35}{U+1D35}{U+1D35}(ttp)Br 與KOH進行取代反應得到Co{U+1D35}{U+1D35}{U+1D35}(ttp)OH, 并最終形成催化劑Co{U+1D35}{U+1D35}(ttp) (Scheme 1, iii-iv)。所以， 溶劑 （THF 或者 {U+2071}PrOH）及H₂O 都可以作為Co{U+1D35}{U+1D35}(ttp) 催化鹵代苯脫鹵形成芳烴的氫的來源。 / This thesis focuses on (1) the base-promoted aryl bromine bond (Ar-Br) cleavages by cobalt(II) porphyrins and (2) catalytic hydrodehalogenation of aryl bromides by cobalt(II) porphyrin in alkaline conditions. / Part I describes the aryl bromine bond cleavage with cobalt(II) porphyrin (Co{U+1D35}{U+1D35}(por)) in the presence of KOH and {U+1D57}BuOH in benzene at 150ºC to give cobalt(III) porphyrin aryls (Co{U+1D35}{U+1D35}{U+1D35}(por)Ar) (eq. 1). / [With images] / Mechanistic studies suggest that CoII(por) first abstracts the bromine atom from the aryl bromide to form aryl radical (Ar) and Co{U+1D35}{U+1D35}{U+1D35}(por)Br (Scheme 1, i). Ar· further reacts with Co{U+1D35}{U+1D35}(por) to generate Co{U+1D35}{U+1D35}{U+1D35}(por)Ar (Scheme 1, ii). Co{U+1D35}{U+1D35}{U+1D35}(por)Br undergoes ligand substitution with KOH to form Co{U+1D35}{U+1D35}{U+1D35}(por)OH, which quickly gives Co{U+1D35}{U+1D35}(por) and H₂O₂ (Scheme 1, iii). H₂O₂ undergoes base-promoted decomposition to form H₂O and O₂ (Scheme 1, iv). / [With images] / Scheme 1 Reaction Mechanism of Base-promoted Ar-Br Cleavage with Co{U+1D35}{U+1D35}(por) / Part II describes the catalytic hydrodehalogenation of aryl bromides by Co{U+1D35}{U+1D35}(ttp) at 200 ºC in alkaline conditions to generate arenes (eq. 2). The reaction can occur in both THF and {U+2071}PrOH. / [With images] / Mechanistic studies suggest that Co{U+1D35}{U+1D35}(ttp) also first abstracts the bromine atom from the aryl bromide in the presence of KOH to form Ar· and Co{U+1D35}{U+1D35}{U+1D35}(ttp)Br (Scheme 2, i). Ar· can abstract a hydrogen atom from the solvent (THF or {U+2071}PrOH) to form arenes (Scheme 2, ii). Ar also could be trapped by Co{U+1D35}{U+1D35}(ttp) to give Co{U+1D35}{U+1D35}{U+1D35}(ttp)Ar, which undergoes hydrolysis in the presence of OH⁻ to the arene (ArH) and Co{U+1D35}{U+1D35}{U+1D35}(ttp)OH (Scheme 2, iii). Co{U+1D35}{U+1D35}{U+1D35}(ttp)Br gives Co{U+1D35}{U+1D35}{U+1D35}(ttp)OH by ligand substitution with KOH and Co{U+1D35}{U+1D35}{U+1D35}(ttp)OH regenerates the catalyst Co{U+1D35}{U+1D35}(ttp) (Scheme 1, iii-iv). The solvent (THF or {U+2071}PrOH) and H₂O are the hydrogen sources for the catalytic dehalogenation of aryl bromides by Co{U+1D35}{U+1D35}(ttp). / Scheme 2 Mechanism of Catalytic Dehalogentaion of ArBr by CoII(ttp) in Alkaline Media / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Liu, Chunran. / "October 2012." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves ). / Abstracts also in Chinese. / Chapter Table of Contents --- p.i / Chapter Acknowledgements --- p.iv / Chapter Abbreviations --- p.v / Chapter Abstract --- p.vi / Chapter Part I --- The Base-promoted Aryl Bromine Bond Cleavage of Aryl Bromides by Cobalt(II) Porphyrins / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter 1.1 --- Introduction to Porphyrins and Group 9 metalloporphyrins --- p.1 / Chapter 1.1.1 --- Porphyrin Ligand --- p.1 / Chapter 1.1.2 --- Group 9 metalloporphyrins --- p.2 / Chapter 1.1.3 --- Chemistry of Group 9 Metalloporphyrin --- p.3 / Chapter 1.1.3.1 --- Chemsitry of M{U+1D35}(por) --- p.3 / Chapter 1.1.3.2 --- Chemsitry of M{U+1D35}{U+1D35}(por) --- p.4 / Chapter 1.1.3.3 --- Chemsitry of M{U+1D35}{U+1D35}{U+1D35}{U+1D35}(por) --- p.4 / Chapter 1.1.3.4 --- Chemsitry of M{U+1D35}{U+1D35}{U+1D35}{U+1D35}(por)OH --- p.6 / Chapter 1.2 --- Physical Properties of Aryl Halides --- p.9 / Chapter 1.3 --- Synthesis of Metalloporphyrin Aryl --- p.10 / Chapter 1.4 --- Modes of Reactivity of Aryl Carbon-Halogen Bond Cleavage by Transition Metal Complexes --- p.11 / Chapter 1.4.1 --- Oxidative Addition (OA) --- p.11 / Chapter 1.4.2 --- Nucleophilic Aromatic Substitution (SNA) --- p.14 / Chapter 1.4.3 --- Halogen Atom Transfer (HXA) --- p.14 / Chapter 1.4.4 --- Radical ipso-Substitution --- p.15 / Chapter 1.5 --- Scope of Part I --- p.16 / Chapter Chapter 2 --- Base-promoted Aryl Bromine Bond Cleavage of Aryl Bromides by Cobalt(II) Porphyrins / Chapter 2.1 --- Introduction --- p.17 / Chapter 2.2 --- Objectives of the Work --- p.18 / Chapter 2.3 --- Preparation of Starting Materials --- p.18 / Chapter 2.3.1 --- Synthesis of Porphyrin --- p.18 / Chapter 2.3.2 --- Synthesis of Cobalt(II) Porphyrin --- p.18 / Chapter 2.3.3 --- Synthesis of Co{U+1D35}{U+1D35}{U+1D35}(ttp)Br --- p.19 / Chapter 2.4 --- Discovery of Ph-Br Bond Cleavage by Co{U+1D35}{U+1D35}(ttp) with KOH --- p.19 / Chapter 2.5 --- Optimization of Reaction Conditions --- p.20 / Chapter 2.5.1 --- {U+1D57}BuOH Effect --- p.20 / Chapter 2.5.2 --- Solvent Effect --- p.21 / Chapter 2.5.3 --- Temperature Effect --- p.21 / Chapter 2.5.4 --- Base Loading Effect --- p.22 / Chapter 2.6 --- Summary of Optimization of the Base-promoted Ph-Br Bond Cleavage by Co{U+1D35}{U+1D35}(ttp) --- p.22 / Chapter 2.7 --- Porphyrin Ligand Effect --- p.23 / Chapter 2.8 --- Substrate Scope of Aryl Bromides --- p.24 / Chapter 2.9 --- Mechanistic Studies --- p.25 / Chapter 2.9.1 --- Possible Pathways of Ar-Br Bond Cleavage --- p.25 / Chapter 2.9.1.1 --- Oxidative Addition (OA) --- p.26 / Chapter 2.9.1.2 --- Nucleophilic Aromatic Substitution (SNA) --- p.27 / Chapter 2.9.1.3 --- Radical ipso-Substitution --- p.28 / Chapter 2.9.1.4 --- Halogen Atom Transfer (HXA) --- p.28 / Chapter 2.9.2 --- Electronic Effect of 4-Substituted ArBr by Hammett Plot --- p.29 / Chapter 2.9.3 --- Proposed Mechanism --- p.32 / Chapter 2.9.4 --- Evidence for Halogen Atom Transfer --- p.33 / Chapter 2.10 --- Conclusion --- p.35 / Chapter Chapter 3 --- Experimental Section --- p.36 / Reference --- p.53 / Chapter Part II --- Catalytic Hydrodehalogenation of Aryl Bromides by Cobalt(II) Porphyrin in Alkaline Conditions / Chapter Chapter 4 --- General Introduction --- p.58 / Chapter 4.1 --- Introduction --- p.58 / Chapter 4.1.1 --- Properties of Halogenated Aromatic Compounds --- p.58 / Chapter 4.1.2 --- Reactivity of Aryl Carbon-Halogen Bond --- p.59 / Chapter 4.2 --- Hydrodehalogenation of Aryl Halides by Transiton Metal Complexes --- p.59 / Chapter 4.2.1 --- Molecular Hydrogen (H₂) --- p.60 / Chapter 4.2.2 --- Alcohols and Metal Alkoxides --- p.61 / Chapter 4.2.3 --- Dimethyformamide (DMF) --- p.64 / Chapter 4.2.4 --- Hydrazine (NH₂-NH₂) --- p.65 / Chapter 4.2.5 --- Metal Hydrides --- p.65 / Chapter 4.2.6 --- Alkyl Grignard Reagents --- p.67 / Chapter 4.2.7 --- Formic Acid and Its Salts --- p.67 / Chapter 4.3 --- Common Reducing Agents --- p.69 / Chapter 4.3 --- Scope of Part II --- p.69 / Chapter Chapter 5 --- Catalytic Hydrodehalogenation of Aryl Bromides by Cobalt(II) Porphyrin in Alkaline Conditions / Chapter 5.1 --- Introduction --- p.70 / Chapter 5.2 --- Objectives of the Work --- p.71 / Chapter 5.3 --- Optimization of Reaction Conditions --- p.71 / Chapter 5.3.1 --- Solvent Effect --- p.71 / Chapter 5.3.2 --- Temperature Effect --- p.72 / Chapter 5.3.3 --- Base Loading Effect --- p.73 / Chapter 5.3.4 --- Porphyrin Loading Effect --- p.73 / Chapter 5.3.5 --- Atmosphere Effect --- p.74 / Chapter 5.4 --- Summary of Optimization of Hydrodehalogention of Aryl Bromides by Co{U+1D35}{U+1D35}(ttp) --- p.74 / Chapter 5.5 --- Substrate Scope of Aryl Bromides --- p.75 / Chapter 5.5.1 --- THF as the Solvent --- p.75 / Chapter 5.5.2 --- {U+2071}PrOH as the Solvent --- p.76 / Chapter 5.6 --- Catalytic Reactivity of Co{U+1D35}{U+1D35}(ttp) as the Catalyst --- p.77 / Chapter 5.7 --- Mechanistic Studies --- p.78 / Chapter 5.7.1 --- Proposed Mechanism of Hydrodehalogenation of Aryl Bromides by Co{U+1D35}{U+1D35}(ttp) --- p.78 / Chapter 5.7.2 --- Hydrogen Source Investigation --- p.80 / Chapter 5.8 --- Conclusion --- p.83 / Chapter Chapter 6 --- Experimental Section --- p.84 / Reference --- p.92 / Chapter Appendix --- Appendix I --- p.101 / Appendix II --- p.112 / Appendix III --- p.118

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

Spectrophotometric titrations for a full series of 4-aminophenyl/4-pyridyl meso-substituted porphyrins were carried out using methanesulfonic acid in DMSO to study the hyperporphyrin effect across different substitution patterns. The series included zero, one, two (cis and trans), three, and four meso(4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups. The peripheral pyridyl groups consistently protonate before the interior porphyrin pyrrole nitrogens, which protonate before the aminophenyl groups. Aminophenyl substituents increase the basicity of the pyrrole nitrogens and lead to distinctive hyperporphyrin spectra with a broad Soret band and a strong red absorption. The structure proposed to give rise to these spectra is the previously proposed charge-transfer interaction between the aminophenyl and the protonated pyrrole. A novel hyperporphyrin structure involving charge-transfer interactions between two peripheral substituents is also proposed in one case - the triply protonated (+3) porphyrin with three aminophenyl and one pyridyl substituents; two of the aminophenyl groups delocalize the charges on the interior nitrogens while the third aminophenyl group delocalizes with the protonated pyridyl. The NMR titrations for a full series of 4-aminophenyl/4-pyridyl meso-substituted porphyrins were also performed by methanesulfonic acid in DMSO. Zero, one, two (cis), three, and four meso(4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups are the primary compounds studied here. The inductive effect of the meso-substituents and the π system of the macrocycle both determine the hyperporphyrin spectra, in which inductive effect has stronger influence on cis-A2Py2P and APy3P. TAPP and A3PyP both show slow exchanges from free base to hyperporphyrin, indicating these hyperporphyrin structures are stable. Both 1H-NMR and 2D NOESY spectra further validate the existence of the novel D-type hyperporphyrin from A3PyPH3+3. Electrochemical studies of these hyperporphyrins were also performed. The porphyrins involved here are zero, two (cis & trans), three, and four meso (4-aminophenyl) groups, with the remaining meso substituents being 4-pyridyl groups. The acid titrations were done in DMSO using methanesulfonic acid. Both TAPP and A3PyP can be extensively reduced with up to five distinct reduction waves. The hyperporphyrin from A3PyP, unlike that from TAPP, shows stable structures during the reduction, and A3PyPH3+3 was proposed to have the ability to reduce protons into hydrogen in a catalytic cycle.

published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

by Andy Kwong Shun Tse. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1995. / Includes bibliographical references (leaves 53-57). / ACKNOWLEDGMENTS --- p.i / ABBREVIATIONS --- p.ii / ABSTRACT --- p.iv / CONTENTS --- p.v / Chapter Part 1: --- Serendipitous Synthesis of Cobalt(III) and Rhodium (III) Porphyrin-phosphoryls / Chapter I. --- INTRODUCTION --- p.1 / Chapter II. --- RESULTS AND DISCUSSIONS --- p.6 / Chapter III. --- CONCLUSION --- p.28 / Chapter Part 2: --- Synthesis of Rhodium(III) Porphyrin-silyls / Chapter I. --- INTRODUCTION --- p.29 / Chapter II. --- RESULTS AND DISCUSSIONS --- p.32 / Chapter III. --- CONCLUSION --- p.41 / EXPERIMENTAL --- p.42 / REFERENCES --- p.53 / APPENDIX I-III --- p.58 / LIST OF SPECTRA --- p.61 / SPECTRA --- p.62