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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.
391

Base-promoted benzylic carbon-hydrogen bond activation and benzlic carbon-carbon bond activation with rhodium (III) porphyrin: scope and mechanism. / CUHK electronic theses & dissertations collection

January 2011 (has links)
Choi, Kwong Shing. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / 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.
392

Activation of carbon-carbon and carbon-silicon bonds of nitriles by rhodium porphyrin radical.

January 2002 (has links)
by Fung Chun-wah. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 117-119). / Abstracts in English and Chinese. / Table of Contents --- p.i / Acknowledgments --- p.v / Abbreviations --- p.vi / Abstract --- p.vii / Chapter PART I: --- ACTIVATION OF CARBON-CARBON BONDS OF NITRILES BY RHODIUM PORPHYRIN RADICAL / Chapter CHAPTER 1 --- General Introduction --- p.1 / Chapter 1.1.1 --- Activation of Carbon-Carbon Bond (CCA) by Transitional Metals --- p.1 / Chapter 1.1.1.1 --- Potential Application of C-C Bond Activation --- p.1 / Chapter 1.1.1.1.1 --- Cracking --- p.1 / Chapter 1.1.1.1.2 --- Depolymerization --- p.2 / Chapter 1.1.1.2 --- Thermodynamic and Kinetic Considerations in CCA --- p.3 / Chapter 1.1.1.3 --- C-C Bond Activation in Strained System --- p.3 / Chapter 1.1.1.4 --- C-C Bond Activation facilitated by Aromatization --- p.7 / Chapter 1.1.1.5 --- C-C Bond Activation of Carbonyl Compounds --- p.9 / Chapter 1.1.1.6 --- C-C Bond Activation of the Nitriles --- p.13 / Chapter 1.1.1.7 --- Selective C-C Bond Activation on a Multimetallic Site --- p.16 / Chapter 1.1.1.8 --- Intramolecular sp2 -sp3 C-C Bond Activation in PCP System --- p.17 / Chapter 1.1.1.9 --- CCA in N-Heterocyclic Carbene --- p.18 / Chapter 1.1.1.10 --- CCA in Pt(0) complexes bearing Chelating P´ةN- and P´ةP- Ligands --- p.19 / Chapter 1. 1.1.11 --- CCA of Alkyne via Hydroiminoacylation by Rh(I) Catalyst --- p.20 / Chapter I. 1.1.12 --- CCA in Homoallylic Alcohol by β-Allyl Elimination --- p.21 / Chapter I. 1.1.13 --- C-C Bond Activation by Metathesis of Alkanes --- p.23 / Chapter I.1.2 --- Structural Features of Rhodium Porphyrins --- p.25 / Chapter I.1.3 --- Objective of the Work --- p.27 / Chapter CHAPTER 2 --- Carbon-Carbon Bond Activation (CCA) of Nitriles by Rhodium Porphyrin Radical --- p.28 / Chapter I.2.1 --- Introduction --- p.28 / Chapter I.2.1.1 --- CCA of Nitroxides by Rhodium(II) Porphyrin Radical Rh(por) --- p.28 / Chapter I.2.2 --- CCA of Nitriles by Rh(tmp) Radical --- p.29 / Chapter I.2.2.1 --- Synthesis of Rh(tmp)Me --- p.29 / Chapter I.2.2.2 --- Synthesis of Rh(tmp) Radical --- p.30 / Chapter I.2.2.3 --- Ligand effect on CCA --- p.31 / Chapter I.2.2.3.1 --- Synthesis of Phosphines --- p.31 / Chapter I.2.2.3.2 --- Reactions between Rh(tmp) and Phosphines --- p.32 / Chapter I.2.2.3.3 --- Synthesis of Alkyl Rh(tmp) --- p.35 / Chapter I.2.2.4 --- CCA of Nitriles by Rh(tmp) with PPh3 added --- p.36 / Chapter I.2.2.4.1 --- Synthesis of Nitrile --- p.36 / Chapter I.2.2.4.2 --- Reactions between Rh(tmp) and Nitriles --- p.37 / Chapter I.2.3.4 --- Proposed Mechanism of CCA --- p.44 / Chapter CHAPTER 3 --- Experimental Section --- p.46 / Conclusion --- p.63 / References --- p.64 / Chapter PART II --- ACTIVATION OF CARBON-SILICON BONDS OF NITRILES BY RHODIUM PORPHYRIN RADICAL --- p.71 / Chapter CHAPTER 1 --- General Introduction --- p.71 / Chapter II. 1.1 --- Carbon-Silicon Bond Activation by Transitional Metals --- p.71 / Chapter II. 1.1.1 --- Potential Application of C-Si Bond Activation --- p.72 / Chapter II.l. l.2 --- C(sp3)-Si Bond Activation --- p.73 / Chapter II. 1.1.2.1 --- Intermolecular C(sp3)-Si Bond Activation in Strained System --- p.73 / Chapter II. 1.1.2.2 --- Intermolecular C(sp3)-Si Bond Activation in Unstrained System --- p.76 / Chapter II. 1.1.3 --- C(sp2)-Si Bond Activation --- p.78 / Chapter II. 1.1.3.1 --- Intermolecular C(aryl)-Si Bond Activation --- p.78 / Chapter II. 1.1.3.2 --- Intramolecular C(aryl)-Si Bond Activation --- p.84 / Chapter II. 1.1.3.3 --- C(vinyl)-Si Bond Activation --- p.87 / Chapter II. 1.1.4 --- C(sp)-Si Bond Activation --- p.89 / Chapter II. 1.2 --- Objective of the Work --- p.92 / Chapter CHAPTER 2 --- Carbon-Silicon Bond Activation (CSA) of Nitriles --- p.93 / Chapter II.2.1 --- Introduction --- p.93 / Chapter II.2.2 --- Reactions between Rh(tmp) Radical and Silylnitriles --- p.93 / Chapter II.2.2.1 --- Investigation the CSA of Trimethylsilylcyanide by Rh(tmp) --- p.93 / Chapter II.2.2.1.1 --- Synthesis of Rh(tmp)SiMe3 --- p.93 / Chapter II.2.2.1.2 --- Synthesis of Rh(tmp)CN --- p.94 / Chapter II.2.2.1.3 --- Reactions between Rh(tmp) and Trimethylsilylcyanide --- p.95 / Chapter II.2.2.1.4 --- Ligands effect on CSA of Trimethylsilylcyanide by Rh(tmp) --- p.98 / Chapter II.2.2.1.5 --- Temperature effect on CSA --- p.101 / Chapter II.2.2.2 --- Reactions between Rh(tmp) and other Silylnitriles --- p.102 / Chapter II.2.3 --- Mechanism of CSA of Trimethylsilylcyanide --- p.103 / Chapter II.2.3.1 --- Proposed Mechanism of CSA of Trimethylsilylcyanide by Rh(tmp) --- p.104 / Chapter II.2.4 --- A Comparison of CSA and CCA of Nitriles --- p.105 / Chapter CHAPTER 3 --- Experimental Section --- p.107 / Conclusion --- p.116 / References --- p.117 / List of Spectra --- p.120 / Spectra --- p.121
393

Synthesis and structural characterization of amido- and imido-lanthanide compounds.

January 2000 (has links)
by Chan Hoi Shan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 111-119). / Abstracts in English and Chinese. / Acknowledgement --- p.iii / Abbreviation --- p.iv / List of Compounds --- p.vi / Abstract --- p.vii / Abstract (Chinese) --- p.ix / Chapter Chapter 1. --- Introduction / Chapter 1.1 --- Lanthanide-Amine Compounds --- p.1 / Chapter 1.2 --- Lanthanide-Amide Compounds --- p.3 / Chapter 1.3 --- Lanthanide-Imide Compounds --- p.11 / Chapter 1.4 --- Some Applications of Lanthanide-Amide Compounds in Organic Synthesis --- p.15 / Chapter 1.5 --- Aims --- p.19 / Chapter Chapter 2. --- Synthesis and Structural Characterization of Anionic and Neutral Dichlorolanthanocene Compounds / Chapter 2.1 --- Synthesis --- p.20 / Chapter 2.2 --- Structural Characterization --- p.22 / Chapter 2.3 --- Conclusion --- p.23 / Chapter Chapter 3. --- Synthesis and Structural Characterization of Amido-Lanthanide Compounds / Chapter 3.1 --- Synthesis and Structural Characterization of Yb(NHAr)3(THF)n --- p.26 / Chapter 3.2 --- "Synthesis and Structural Characterization of Yb(NHC6H3iPr2- 2,6)4Na(THF)" --- p.38 / Chapter 3.3 --- "Synthesis and Structural Characterization of Yb(Cp"")(NHAr)2(L)" --- p.45 / Chapter 3.4 --- "Synthesis and Structural Characterization of Yb(Cp"")(NHC6H3iPr2- 2,6)3M(L)" --- p.54 / Chapter 3.5 --- Synthesis and Structural Characterization of Yb(NHAr)3(NH2Ar)(L) --- p.74 / Chapter 3.6 --- Conclusion --- p.76 / Chapter Chapter 4. --- Synthesis and Structural Characterization of Imido-Lanthanide Compounds / Chapter 4.1 --- Synthesis --- p.81 / Chapter 4.2 --- Structural Characterization --- p.82 / Chapter 4.3 --- Conclusion --- p.85 / Chapter Chapter 5. --- Summary and Remarks / Chapter 5.1 --- Summary --- p.96 / Chapter 5.2 --- Remarks --- p.97 / Chapter Chapter 6. --- Experimental Section --- p.98 / References --- p.111 / Appendix --- p.120
394

Tantalum and niobium alkylidene complexes via ligand induced alpha-hydrogen abstraction.

Rupprecht, Gregory Andrew January 1979 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1979. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Vita. / Includes bibliographical references. / Ph.D.
395

Transition-Metal Complexes Catalyzed Hydrogen Atom Transfer: Kinetic Study and Applications to Radical Cyclizations

Li, Gang January 2015 (has links)
Radical cyclizations have been proven to be extremely important in organic synthesis. However, their reliance on toxic trialkyltin hydrides has precluded their practical applications in pharmaceutical manufacturing. Many tin hydride substitutes have been suggested but none of them are adequate alternates to the traditional tin reagent. Transition-metal hydrides have been shown to catalyze the hydrogenation and hydroformylation of unsaturated carbon-carbon bonds. Theses reactions begin with a Hydrogen Atom Transfer (HAT) from a metal to an olefin, generating a carbon-centered radical. The cyclization of that radical is an effective route to five- and six-membered rings. The HAT will be fastest if the M–H bond is weak. However, making the reaction catalytic will require that the hydride can be regenerated with H2. HCr(CO)3Cp has proven to be a good catalyst for such cyclizations, but it suffers from air sensitivity. The yield of the cyclization product depends on how the rate of radical cyclization compares with the rates of side reactions (hydrogenation and isomerization), so special substituents on a substrate are best installed to increase the cyclization rate. In attempting to improve the efficiency of radical cyclization I have studied the effect of substituents on the target double bond on the rate of cyclization. A single phenyl substituent has proven to stabilize a radical better than two phenyls. This stabilization leads to faster cyclizations and a higher cyclization yield. I also have found that Co(dmgBF2)L2 (L = THF, H2O, MeOH…) under H2 is an effective hydrogen atom donor. I have monitored by NMR the catalysis by the system of the hydrogenation of stable radicals (trityl radical and TEMPO radical) and found the rate-determining step to be the activation of hydrogen gas by CoII. The reactive form of the complex is five-coordinated cobalt complex Co(dmgBF2)2L. The Co/H2 system can also transfer hydrogen atom to C=C bonds, thus initiate radical cyclizations. The resting state of the cobalt is the CoII metalloradical, so a cycloisomerization is obtained. Such a reaction neither loses nor adds any atom and has 100% atom economy.
396

Computational studies of some pericyclic reactions.

January 2005 (has links)
Ho Ho-On. / Thesis submitted in: August 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references. / Abstracts in English and Chinese. / Thesis Committee --- p.i / Abstract --- p.ii / Acknowledgements --- p.iv / Table of Contents --- p.v / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- The Gaussian-3 Method --- p.1 / Chapter 1.2 --- The G3 Method with Reduced MΦller-Plesset Order and Basis Set --- p.2 / Chapter 1.3 --- Calculation of Thermodynamical Data --- p.2 / Chapter 1.4 --- Remark on the Location of Transition Structures --- p.3 / Chapter 1.5 --- Natural Bond Orbital (NBO) Analysis --- p.3 / Chapter 1.6 --- Scope of the Thesis --- p.4 / Chapter 1.7 --- References --- p.4 / Chapter Chapter 2 --- The Important Basic Concepts of Ab Initio Calculations and Their Application to Pericyclic Reactions --- p.6 / Chapter 2.1 --- Potential Energy Surfaces --- p.6 / Chapter 2.2 --- Ab Initio Method --- p.6 / Chapter 2.2.1 --- Basic Sets --- p.7 / Chapter 2.2.2 --- Correlation Methods --- p.8 / Chapter 2.3 --- Pericyclic Reaction --- p.10 / Chapter 2.4 --- The Perturbation Theory of Reactivity --- p.10 / Chapter 2.5 --- References --- p.11 / Chapter Chapter 3 --- Ab Initio Study of the Cycloaddition Reaction between Ethylene and Butadiene as well as That between Ethylene and Hexatriene --- p.13 / Chapter 3.1 --- Introduction --- p.13 / Chapter 3.2 --- Methods of Calculation --- p.15 / Chapter 3.3 --- Results and Discussion --- p.15 / Chapter 3.3.1 --- Reaction between ethylene and butadiene --- p.30 / Chapter 3.3.2 --- Reaction between ethylene and hexatriene --- p.34 / Chapter 3.3.3 --- Electrocyclic reaction of hexatriene --- p.37 / Chapter 3.4 --- Conclusion --- p.40 / Chapter 3.5 --- References --- p.41 / Chapter Chapter 4 --- A G3(MP2) Study on the Electrocyclic Reactions of [12]annulene --- p.43 / Chapter 4.1 --- Introduction --- p.43 / Chapter 4.2 --- Methods of Calculation --- p.44 / Chapter 4.3 --- Results and Discussion --- p.45 / Chapter 4.4 --- Summary --- p.51 / Chapter 4.5 --- Conclusion --- p.52 / Chapter 4.6 --- References --- p.52 / Chapter Chapter 5 --- A G3(MP2) Study on the Cycloaddition Reactions between Ethylene and Azines as well as Other Related Systems --- p.54 / Chapter 5.1 --- Introduction --- p.54 / Chapter 5.2 --- Methods of Calculation --- p.55 / Chapter 5.3 --- Results and Discussion --- p.55 / Chapter 5.3.1 --- Addition of ethylene to azines --- p.55 / Chapter 5.3.2 --- "Addition of ethylene to quinolene, isoquinolene and 1,8-naphthyridine" --- p.64 / Chapter 5.4 --- Conclusion --- p.70 / Chapter 5.5 --- References --- p.70 / Chapter Chapter 6 --- Conclusion --- p.72 / Appendix A Energetic and Bonding Investigation of Phosphabenzene and Arsabenzene: A Gaussian-3 Study --- p.73 / Chapter A.1 --- Introduction --- p.73 / Chapter A.2 --- Methods of Calculation --- p.73 / Chapter A.3 --- Results and Discussion --- p.74 / Chapter A.4 --- Conclusion --- p.77 / Chapter A.5 --- References --- p.77 / Appendix B Energetic and Bonding Study of Hexamethylenetetramine (HMT) and Fourteen Related Cage Molecules: A G3(MP2) Investigation --- p.79 / Chapter B.1 --- Introduction --- p.79 / Chapter B.2 --- Methods of Calculation --- p.80 / Chapter B.3 --- Results and Discussion --- p.80 / Chapter B.4 --- Conclusion --- p.87 / Chapter B.5 --- References --- p.87 / Appendix C The Gaussian-3 Theoretical Models --- p.89 / Chapter C.1 --- The G3 Theory --- p.89 / Chapter C.2 --- The G3(MP2) Theory --- p.90 / "Appendix D Calculation of Enthalpy at 298 K, H298" --- p.91
397

Selective carbon(CO)-carbon(α) bond activation of ketones by rhodium porphyrin complex and aldehydic carbon-hydrogen bond activation by iridium porphyrin complex. / Selective carbon(carbonyl)-carbon(alpha) bond activation of ketones by rhodium porphyrin complex and aldehydic carbon-hydrogen bond activation by iridium porphyrin complex

January 2013 (has links)
本論文主要探討銠卟啉和銥卟啉絡合物,分別與酮類與醛類進行的鍵活化化學。 / 第一部分主要介紹由β-乙基羥基銠卟啉絡合物(Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH)與酮類進行的羰基碳及α-碳(C(CO)-C(α)) 鍵活化(下稱碳碳鍵活化)。於室溫至50ºC時,在非溶劑的條件下,Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH選擇性地斷裂芳香酮和脂肪酮類的C(CO)-C(α)鍵,生成相對應的銠卟啉酰基絡合物(Rh{U+1D35}{U+1D35}{U+1D35}(ttp)COR, R = 烷基或芳基),產率最高可達80%。作為銠卟啉羥基絡合物(Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH)的前體,Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH的活性展示出Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH是碳碳鍵活化的重要中間體。 / 第二部分主要介紹由β-乙基羥基銥卟啉絡合物(Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH)與芳香醛類進行,具選擇性的醛碳氫鍵活化。在160ºC和非溶劑的條件下,Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH與芳香醛類反應,生成相對應的銥卟啉酰基絡合物(Ir{U+1D35}{U+1D35}{U+1D35}(ttp)COAr)作為碳氫鍵活化產物,產率最高可達72%。銥卟啉羥基絡合物(Ir{U+1D35}{U+1D35}{U+1D35}(ttp)OH)和乙烯配位銥卟啉絡合正離子((CH₂=CH₂)Ir{U+1D35}{U+1D35}{U+1D35}(ttp)⁺)被推斷為醛碳氫鍵活化的可能中間體。 / This research focuses on the bond activation chemistry by rhodium and iridium porphyrin complexes with ketones and aldehyde respectively. / Part 1 describes the C(CO)-C(α) bond activation (CCA) of ketones by Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH (ttp = 5,10,15,20-tetratolylporphyrinato dianion). Rh{U+1D35}{U+1D35}{U+1D35}(ttp)- CH₂CH₂OH selectively cleaved the C(CO)-C(α) bond of aromatic and aliphatic ketones in solvent-free conditions at room temperature to 50ºC, giving the corresponding rhodium(III) porphyrin acyls (Rh{U+1D35}{U+1D35}{U+1D35}(ttp)COR, R = alkyl or aryl) up to 80% yield. The activity of the Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH precursor, Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH, demonstrates Rh{U+1D35}{U+1D35}{U+1D35}(ttp)OH as the key intermediate in the CCA of ketones. / [With images]. / Part 2 describes the selective aldehydic carbon-hydrogen bond activation (CHA) of aryl aldehydes by Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH. Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH reacted with aryl aldehydes in solvent-free conditions at 160ºC to give the corresponding iridium(III) porphyrin acyls (Ir{U+1D35}{U+1D35}{U+1D35}(ttp)COAr) as the CHA products up to 72% yield. Ir{U+1D35}{U+1D35}{U+1D35}(ttp)OH and (CH₂=CH₂)Ir{U+1D35}{U+1D35}{U+1D35}(ttp)⁺ were proposed as the possible intermediate for the CHA reaction. / [With images]. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Chan, Chung Sum. / "November 2012." / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references. / Abstracts also in Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Table of Contents --- p.iv / Abbreviations --- p.vii / Structural Abbreviations of Porphyrin --- p.viii / Chapter Part 1 --- Carbon-Carbon Bond Activation of Ketones with Rhodium(III) Porphyrin β-Hydroxyethyl --- p.1 / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Properties of Ketones --- p.1 / Chapter 1.2 --- Carbon(CO)-Carbon(α) Bond Activation (CCA) of Ketones --- p.2 / Chapter 1.2.1 --- CCA of Ketones by Transition Metal Complexes --- p.2 / Chapter 1.2.2 --- CCA of Ketones by Metalloporphyrins --- p.5 / Chapter 1.3 --- Porphyrin Ligands and Rhodium(III) Porphyrins --- p.7 / Chapter 1.3.1 --- Porphyrin Ligands --- p.7 / Chapter 1.3.2 --- Rhodium(III) Porphyrins --- p.8 / Chapter 1.4 --- Rhodium(III) Porphyrin Hydroxide --- p.10 / Chapter 1.4.1 --- Nature of Bonding in Late Transition Metal Hydroxides --- p.10 / Chapter 1.4.1.1 --- Hard-Soft Acid-Base principle --- p.11 / Chapter 1.4.1.2 --- dπ-pπ Interaction Model --- p.11 / Chapter 1.4.1.3 --- E-C Model --- p.12 / Chapter 1.4.2 --- Attempted Preparation of Rhodium(III) Porphyrin Hydroxides --- p.13 / Chapter 1.4.3 --- Chemistry of Rhodium(III) Porphyrin Hydroxides --- p.15 / Chapter 1.5 --- Rhodium(III) Porphyrin β-hydroxyethyl as Rhodium(III) Hydroxide Precursor --- p.18 / Chapter 1.6 --- Objective --- p.20 / Chapter Chapter 2 --- Carbon-Carbon Bond Activation of Ketones with Rhodium(III) Porphyrin β-Hydroxyethyl --- p.21 / Chapter 2.1 --- Preparation of Starting Materials --- p.21 / Chapter 2.1.1 --- Synthesis of Porphyrin --- p.21 / Chapter 2.1.2 --- Synthesis of Rhodium(III) Porphyrins --- p.21 / Chapter 2.2 --- CCA of Diisopropyl Ketone by Rh{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH --- p.22 / Chapter 2.3 --- Optimization of Reaction Conditions --- p.22 / Chapter 2.3.1 --- Atmosphere Effect --- p.22 / Chapter 2.3.2 --- PPh3 Effect --- p.23 / Chapter 2.3.3 --- Solvent Effect --- p.24 / Chapter 2.4 --- Substrate Scope --- p.26 / Chapter 2.4.1 --- CCA of Isopropyl Ketones --- p.26 / Chapter 2.4.2 --- CCA of Non-Isopropyl Ketones --- p.28 / Chapter 2.5 --- Proposed Mechanism --- p.29 / Chapter 2.6 --- Comparison on CCA of Ketones by Different Rh{U+1D35}{U+1D35}{U+1D35}(por)OH Sources --- p.31 / Chapter 2.6.1 --- Reaction Conditions --- p.31 / Chapter 2.6.2 --- Substrate Scope --- p.32 / Chapter 2.6.3 --- Regioselectivity --- p.33 / Chapter 2.7 --- Comparison on Bond Activation of Carbonyl Compounds by Rhodium Porphyrin β-Hydroxyethyl --- p.34 / Chapter 2.8 --- CCA of Ketones with Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH --- p.36 / Chapter 2.9 --- Conclusion --- p.37 / Chapter Chapter 3 --- Experimental Sections --- p.39 / References --- p.54 / List of Spectra I --- p.59 / Spectra --- p.60 / Chapter Part 2 --- Aldehydic Carbon-Hydrogen Bond Activation with Iridium(III) Porphyrin β-Hydroxyethyl --- p.63 / Chapter Chapter 1 --- Introduction --- p.63 / Chapter 1.1 --- Properties of Aldehydes --- p.63 / Chapter 1.2 --- Carbon-Hydrogen Bond Activation (CHA) of Aldehydes --- p.64 / Chapter 1.2.1 --- CHA of Aldehydes by Transition Metal Complexes --- p.64 / Chapter 1.2.2 --- Aldehydic CHA by Metalloporphyrins --- p.74 / Chapter 1.3 --- Iridium(III) Porphyrins --- p.77 / Chapter 1.4 --- Iridium(III) Porphyrin Hydroxide --- p.78 / Chapter 1.4.1 --- Attempted Preparation of Iridium(III) Porphyrin Hydroxides --- p.78 / Chapter 1.4.2 --- Chemistry of Iridium(III) Porphyrin Hydroxides --- p.81 / Chapter 1.5 --- Iridium(III) Porphyrin β-hydroxyethyl as Iridium(III) Hydroxide Precursor --- p.83 / Chapter 1.6 --- Objective --- p.85 / Chapter Chapter 2 --- Aldehydic Carbon-Hydrogen Bond Activation with Iridium(III) Porphyrin β-Hydroxyethyl --- p.86 / Chapter 2.1 --- Preparation of Iridium(III) Porphyrins --- p.86 / Chapter 2.2 --- Aldehydic CHA of Benzaldehyde by Ir{U+1D35}{U+1D35}{U+1D35}(ttp)CH₂CH₂OH --- p.87 / Chapter 2.3 --- Optimization of Reaction Conditions --- p.87 / Chapter 2.3.1 --- Temperature Effect --- p.87 / Chapter 2.3.2 --- Solvent Effect --- p.88 / Chapter 2.3.3 --- PPh₃ Effect --- p.90 / Chapter 2.4 --- Substrate Scope --- p.93 / Chapter 2.5 --- Proposed Mechanism --- p.94 / Chapter 2.6 --- Conclusion --- p.96 / Chapter Chapter 3 --- Experimental Sections --- p.97 / References --- p.108 / List of Spectra II --- p.112 / Spectra --- p.112
398

Selective carbon(carbonyl)-carbon(α) bond activation of ketones by group 9 metalloporphyrins. / Selective carbon(carbonyl)-carbon(alpha) bond activation of ketones by group 9 metalloporphyrins / Selective carbon(CO)-carbon(α) bond activation of ketones by group 9 metalloporphyrins / CUHK electronic theses & dissertations collection

January 2012 (has links)
本文主要探討在有水的條件下,分別以銠卟啉和鈷卟啉絡合物與無張酮反應發生選擇羰基碳及α碳(C(CO)-C(α))鍵活化(下稱碳碳鍵活化)的反應活性和反應機。 / 在200°C,無張芳香和脂肪酮與5, 10, 15, 20-(四甲苯) 銠卟啉絡合物(RhIII(ttp)X,X = Cl 和Me)進反應,生成相對應的碳碳鍵活化產物-銠卟啉酰基絡合物,產最高可達97%。與甲基和乙基酮衍生物相比,丙基酮衍生物有較高的活性,而且丙基酮衍生物的碳碳鍵活化反應甚至能在50°C 的低溫條件下進。 / 根據化學計學,環酮的碳碳鍵開環反應顯示RhIII(ttp)OH 是斷開C(CO)-C(α)鍵的中間體。 / 進一步的反應機研究表明, RhIII(ttp)OH 的羥基是從水中得。RhIII(ttp)X首先進α碳氫鍵活化生成動學產物。經過水解,α碳氫鍵活化產物可以重新形成RhIII(ttp)OH。然後,RhIII(ttp)OH 繼續進碳碳鍵活。 / 另外,經濟的5, 10, 15, 20-(四甲苯) 鈷卟啉絡合物與丙基酮衍生物反應,在室溫下可選擇性進碳碳鍵活化並得到鈷卟啉酰基化合物,產最高達82%。根據化學計學,CoIII(ttp)OH 被認為是碳碳鍵活化的中間體。CoIII(ttp)OH很有可能是通過鈷卟啉與水的歧化反應生成的。 / This thesis focuses on the reactivities and mechanistic studies of the rhodium and cobalt porphyrins (M(por)X) assisted selective carbon(CO)-carbon(α) bond activation (CCA) of unstrained ketones with water. / Unstrained aromatic and aliphatic ketones reacted with 5,10,15,20-tetratolylporphyrinato rhodium(III) complexes, Rh[superscript III](ttp)X (X = Cl and Me), at 200°C to give the corresponding rhodium porphyrin acyls as the CCA products up to 97% yield. Isopropyl ketones exhibit much higher reactivities over methyl and ethyl ketones and the CCA can even occur at a low temperature of 50 °C. / The ring openmg CCA of cyclic ketones suggests the carbon(CO)-carbon(α)bond is cleaved by Rh(ttp )OH according to the reaction stoichiometry. / Further mechanistic investigations suggest that water is the source of hydroxyl group to form Rh[superscript III](ttp)OH. Rh[superscript III](ttp)X first undergoes α-carbon-hydrogen bond activation (α-CHA) to give a kinetic product. Hydrolysis of the α-CHA complex affords Rh[superscript III](ttp)OH for subsequent CCA process. / Alternatively, the economically attractive 5,1 0,15,20-tetratolylporphyrinato cobalt(II) complexes, Co[superscript II](ttp), reacted chemoselectively with isopropyl ketones at the carbon(CO)-carbon(α) bond under room temperature to give high yields of cobalt porphyrin acyls up to 82% yields. Co[superscript III](ttp)OH is identified to be the CCA intermediate as suggested by the reaction stoichiometry. Generation of Co[superscript III](ttp )OH from Co[superscript II](ttp) via the disproportionation with water is proposed. / 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. / Fung, Hong Sang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / 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. / Abstract --- p.i / Acknowledgements --- p.iv / Table of Contents --- p.v / Abbreviations --- p.ix / Structural Abbreviations for Porphyrins --- p.x / Chapter Chapter 1 --- General Introduction --- p.1 / Chapter 1.1 --- General Introduction to Carbon-Carbon Bond Cleavage --- p.1 / Chapter 1.1.1 --- Organic Examples of Carbon-Carbon Bond Cleavage --- p.1 / Chapter 1.1.2 --- Carbon-Carbon Bond Activation with Transition Metal 2Complexes --- p.2 / Chapter 1.1.2.1 --- Ring Strain Relief --- p.2 / Chapter 1.1.2.2 --- Chelation Assistance --- p.3 / Chapter 1.1.2.3 --- Aromatization --- p.3 / Chapter 1.1.2.4 --- Carbonyl Functionality --- p.4 / Chapter 1.1.2.5 --- β-Alkyl Elimination --- p.4 / Chapter 1.1.2.6 --- Formal Alkane Metathesis --- p.5 / Chapter 1.2 --- Carbon-Carbon Bond Cleavage of Ketones --- p.6 / Chapter 1.2.1 --- Properties of Ketones --- p.6 / Chapter 1.2.2 --- Organic Examples of Carbon-Carbon Bond Cleavage of Ketones --- p.7 / Chapter 1.2.2.1 --- Haloform Reaction --- p.8 / Chapter 1.2.2.2 --- Haller-Bauer Reaction --- p.8 / Chapter 1.2.2.3 --- Baeyer-Villiger & Dakin Oxidation --- p.9 / Chapter 1.2.2.4 --- Beckmann & Schmidt Rearrangement --- p.10 / Chapter 1.2.2.5 --- Favorskii Rearrangement --- p.11 / Chapter 1.2.2.6 --- Norrish Type I Reaction --- p.12 / Chapter 1.2.2.7 --- Hydrolysis with Water --- p.12 / Chapter 1.2.3 --- Carbon(CO)-Carbon(α) Bond Activation of Ketones with Transition Metal Complexes --- p.13 / Chapter 1.2.3.1 --- Stoichiometric C(CO)-C(α) Bond Activation of Ketones --- p.18 / Chapter 1.2.3.1.1 --- Metal Insertion into Strained Ring --- p.18 / Chapter 1.2.3.1.2 --- Decarbonylation --- p.19 / Chapter 1.2.3.1.3 --- Chelation Assisted CCA of Unstrained Ketones --- p.19 / Chapter 1.2.3.1.4 --- Reaction with Benzyne Complex --- p.20 / Chapter 1.2.3.1.5 --- Reaction with Metal Hydroxide --- p.21 / Chapter 1.2.3.2 --- Catalytic C(CO)-C(α) Bond Activation of Ketones --- p.22 / Chapter 1.2.3.2.1 --- Decarbonylation --- p.22 / Chapter 1.2.3.2.2 --- Insertion with Unsaturated Compounds --- p.23 / Chapter 1.2.3.2.3 --- Hydrogenolysis --- p.24 / Chapter 1.2.3.2.4 --- Ring Fusion --- p.25 / Chapter 1.3.3.2.5 --- [4+2+2] Annulation --- p.26 / Chapter 1.2.3.2.6 --- Alcoholysis and Aminolysis --- p.27 / Chapter 1.2.3.2.7 --- Hydroarylation --- p.28 / Chapter 1.2.3.2.8 --- Arylative Ring Expansion with Alkynes --- p.29 / Chapter 1.3 --- Water as An Oxidizing Agent --- p.29 / Chapter 1.3.1 --- Water-Gas Shift Reaction --- p.30 / Chapter 1.3.2 --- Hydration of C-C π-Bond --- p.31 / Chapter 1.3.3 --- Cleavage of C≡C Bond --- p.31 / Chapter 1.3.4 --- Oxidation of C-H Bond --- p.32 / Chapter 1.4 --- Transition Metal Hydroxide Chemistry --- p.33 / Chapter 1.4.1 --- Preparation of Group 9 Metal Hydroxides --- p.34 / Chapter 1.4.1.2 --- Ligand Substitution --- p.34 / Chapter 1.4.1.3 --- Oxidative Addition --- p.34 / Chapter 1.4.1.4 --- Hydrolysis --- p.35 / Chapter 1.4.2 --- Chemistry of Transition Metal Hydroxide --- p.35 / Chapter 1.5 --- Introduction to Porphyrins and Group 9 Metalloporphyrins --- p.37 / Chapter 1.5.1 --- Porphyrin Ligand --- p.37 / Chapter 1.5.2 --- Metalloporphyrins --- p.38 / Chapter 1.5.3 --- Chemistry of Group 9 Metalloporphyrins --- p.39 / Chapter 1.5.3.1 --- M[superscript I](por) Chemistry --- p.40 / Chapter 1.5.3.2 --- M[superscript II](por) Chemistry --- p.41 / Chapter 1.5.3.3 --- M[superscript III](por) Chemistry --- p.44 / Chapter 1.5.4 --- Equilibration of MI(por), MI (por) and MIII(por) --- p.46 / Chapter 1.5.5 --- Chemistry of Group 9 Metalloporphyrin Hydroxide --- p.47 / Chapter 1.5.5.1 --- Metalloether Formation --- p.47 / Chapter 1.5.5.2 --- Reductive Dimerization --- p.48 / Chapter 1.5.5.3 --- Oxidation --- p.49 / Chapter 1.5.5.4 --- Carbon-Hydrogen Bond Activation --- p.50 / Chapter 1.5.5.5 --- Carbon-Carbon Bond Activation --- p.51 / Chapter 1.6 --- Scope of Thesis --- p.52 / Chapter Chapter 2 --- Carbon(CO)-Carbon(α) Bond Activation of Ketones with Rhodium(lII) Porphyrin Complexes --- p.63 / Chapter 2.1 --- Introduction --- p.63 / Chapter 2.2 --- Objectives of the Work --- p.66 / Chapter 2.3 --- Preparation of Starting Materials --- p.66 / Chapter 2.3.1 --- Synthesis of Porphyrin --- p.66 / Chapter 2.3.2 --- Synthesis of Rhodium(III) Porphyrin Chloride --- p.67 / Chapter 2.3.3 --- Synthesis of Rhodium(III) Porphyrin Methyl --- p.67 / Chapter 2.3.4 --- Synthesis of Rh[superscript III](ttp)H --- p.68 / Chapter 2.3.5 --- Synthesis of Rh[superscript II]₂(ttp)₂ --- p.68 / Chapter 2.3.6 --- Synthesis of Rh[superscript I](ttp)-Na⁺ --- p.68 / Chapter 2.4 --- Optimization of Reaction Conditions with Acetophenone --- p.68 / Chapter 2.4.1 --- Reaction with Rh[superscript III](ttp )OTf, Rh[superscript III](ttp)Cl and Rh[superscript III](ttp)Me --- p.68 / Chapter 2.4.2 --- Temperature Effect --- p.70 / Chapter 2.4.3 --- Porphyrin Ligand Effect --- p.70 / Chapter 2.5 --- Substrate Scope of the CCAReaction --- p.71 / Chapter 2.5.1 --- CCA of Acetophenones --- p.71 / Chapter 2.5.2 --- CCA of Aromatic and Aliphatic Ketones --- p.72 / Chapter 2.6 --- Low Temperature CCA with Isopropyl Ketones --- p.76 / Chapter 2.7 --- Oxidation of the C(CO)-C(α) Bond --- p.77 / Chapter 2.8 --- Water as a Source of Oxidant --- p.80 / Chapter 2.9 --- Regioselectivity of CCA --- p.81 / Chapter 2.1 --- 0 X-ray Structure Determination --- p.83 / Chapter 2.11 --- Mechanistic Studies --- p.92 / Chapter 2.11.1 --- Proposed Mechanism --- p.92 / Chapter 2.11.2 --- Aldol Condensation Catalyzed by Rh(ttp)X (X = Me or Cl) --- p.93 / Chapter 2.11.3 --- Carbon-Hydrogen Bond Activation with Rh(ttp)X (X = Me or Cl) --- p.94 / Chapter 2.11.4 --- Hydrolysis of the α-CHA Product 100 --- p.100 / Chapter 2.11.5 --- Carbon(CO)-Carbon(α) Bond Oxidation with Rh(ttp)OH --- p.102 / Chapter 2.11.6 --- Dehydrogenation of Alcohol --- p.108 / Chapter 2.11.7 --- Thermodynamic Consideration --- p.109 / Chapter 2.12 --- Conclusion --- p.110 / Chapter Chapter 3 --- Carbon(CO)-Carbon(α) Bond Activation of Ketones with Cobalt(II)Porphyrin Complexes --- p.114 / Chapter 3.1 --- Introduction --- p.114 / Chapter 3.2 --- Objectives of the Work --- p.115 / Chapter 3.3 --- Preparation of Starting Materials --- p.115 / Chapter 3.3.1 --- Synthesis of H₂(tp-clPP) --- p.115 / Chapter 3.3.2 --- Synthesis of Co[superscript II] (por) --- p.116 / Chapter 3.4 --- Strategies of C(CO)-C(α) Bond Activation with Cobalt(II) Porphyrins --- p.116 / Chapter 3.5 --- Optimization of Reaction Conditions with Diisopropyl Ketone --- p.118 / Chapter 3.5.1 --- Solvent Effect --- p.118 / Chapter 3.5.2 --- Water Effect --- p.119 / Chapter 3.5.3 --- PPh3 Effect --- p.120 / Chapter 3.5.4 --- Porphyrin Ligand Effect --- p.121 / Chapter 3.5.5 --- Temperature Effect --- p.122 / Chapter 3.6 --- CCA of Isopropyl Ketones --- p.123 / Chapter 3.7 --- X-ray Structure Determination --- p.126 / Chapter 3.8 --- Mechanistic Studies --- p.131 / Chapter 3.8.1 --- Proposed Mechanism --- p.131 / Chapter 3.8.2 --- Disproportionation of Co[superscript II](ttp) with Water --- p.132 / Chapter 3.8.3 --- Dehydrogenation of Co[superscript III](ttp)H --- p.132 / Chapter 3.8.4 --- C(CO)-C(α) Bond Activation --- p.134 / Chapter 3.8.5 --- Dehydrogenation of the Alcohol --- p.134 / Chapter 3.8.6 --- Overall Enthalpy Change --- p.134 / Chapter 3.9 --- Stoichiometric Functionalization --- p.135 / Chapter 3.10 --- Conclusion --- p.138 / Chapter Chapter 4 --- Comparison on Carbon-Carbon Bond Activation by Cobalt, Rhodium and Iridium Porphyrin --- p.142 / Chapter 4.1 --- Introduction --- p.142 / Chapter 4.2 --- Reactivities of Metalloporphyrins --- p.143 / Chapter 4.3 --- Thermodynamic of CCA --- p.144 / Chapter 4.4 --- Rate of CCA --- p.147 / Chapter 4.5 --- Scope and Reactivities of Ketones --- p.147 / Chapter 4.6 --- Regioselectivities --- p.149 / Chapter 4.7 --- Chemoselectivity --- p.150 / Chapter 4.8 --- Conclusion --- p.152 / Chapter Chapter 5 --- Experimental Section --- p.153 / Appendices --- p.181
399

Synthesis, molecular structure and reactivity studies of organolanthanide Fluoride and Carborane compounds. / CUHK electronic theses & dissertations collection

January 2000 (has links)
Kwoli Chui. / "August 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (p. 122-140). / 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.
400

Carbon-carbon bond activation of nitroxides and nitriles by rhodium(II) porphyrin. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Mechanistic investigation has been carried out for the reaction between Rh(tmp) and the nitroxide, 2,2,6,6-tetramethyl-piperidine-1-oxyl (TEMPO). Mechanistically, Rh(tmp) at first coordinated with one molecule of TEMPO to produce a 1:1 adduct. Through this complex, parallel major carbon-carbon bond activation (CCA) and minor carbon-hydrogen bond activation (CHA) occurred. CCA was more favorable at higher reaction temperatures. The CHA product Rh(tmp)H further reacted with excess TEMPO to produce Rh(tmp) again for further CCA and CHA. The overall activation reaction was found to follow second order kinetics, rate = k [Rh(tmp)] [TEMPO]. / Rhodium(II) meso-tetramesitylporphyrin (Rh(tmp)) has been prepared successfully by photolysis of Rh(tmp)Me under anaerobic conditions at low temperature. / The activation of carbon-carbon bond with high reactivity and selectivity has attracted many organometallic chemists due to its fundamental importance in basic chemical research and potential utility in organic synthesis. / The aliphatic, unstrained carbon-carbon bonds of a series of nitroxides 1,1,3,3-tetraalkylisoindolin-2-oxyl have been activated by Rh(tmp). In long chain alkyl substituted nitroxides, regioselective carbon-carbon bond activations were observed. This was attributed to the cooperative effects of the bond dissociation energy and the steric hindrance of alkyl groups in nitroxides. While PPh3 was used as the fifth ligand, the yields of regioselective CCA changed. For sterically less hindered nitroxides, the total yield of CCA increased. For sterically more hindered nitroxides, the total yield of CCA decreased. These can be attributed to the cooperation of steric and electronic effects in the rhodium porphyrin complexes and nitroxides. / The C(sp3)-C(sp3) bonds of a series of alpha-alkylphenylacetonitriles have been activated by Rh(tmp) using PPh3 as the optimized fifth ligand. The activation was not regioselective. The CCA yield was affected by bond energy and steric hindrance of the nitriles. The optimal reaction temperature was 130 °C. / Under same reaction conditions, CCA between Rh(tmp) and 2-alkylbenzonitriles also was carried out. Only C(sp3)-C( sp3) bond was activated. CCA yield depended on the BDE of C-C bond in alkyl substituents. / by Li Xinzhu. / "June 2006." / Adviser: Kin Shing Chan. / Source: Dissertation Abstracts International, Volume: 67-11, Section: B, page: 6396. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 197-210). / 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.

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