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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.
201

An approach to the synthesis of some nitrogen analogues of bridged annulenes.

January 1979 (has links)
Pang Sik Wing. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1979. / Bibliography: leaves 70-73. / Acknowledgement --- p.i / Abstract --- p.ii / Chapter Section I --- Introduction -- Annulenes, azaannulenes, bridged annulenes, and bridged azaannulenes --- p.1 / Chapter Section II --- Synthetic Plans --- p.19 / Chapter Section III --- Results and Discussions --- p.26 / Chapter Section IV --- Experimental --- p.51 / Bibliography --- p.70 / List of Spectra
202

The synthesis of 4-substituted indoles and their elaboration to the ergot alkaloids

Liang, Paul Hsiao-tseng January 1981 (has links)
Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / by Paul Hsiao-tseng Liang. / Ph.D.
203

The synthesis of fluorocarbon monomers and polymers by direct fluorination.

Gerhardt, Glenn Edward January 1978 (has links)
Thesis. 1978. Ph.D.--Massachusetts Institute of Technology. Dept. of Chemistry. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND SCIENCE. / Includes bibliographical references. / Ph.D.
204

Manganese(III) acetate catalyzed allylic oxidation.

January 2005 (has links)
Su Pak Lee. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 79-84). / Abstracts in English and Chinese. / Table of Contents --- p.i / Acknowledgement --- p.iii / Abstract --- p.iv / Abbreviation --- p.vi / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- General Background --- p.1 / Chapter 1.2 --- Stoichiometric Oxidant --- p.4 / Chapter 1.2.1 --- Chromium Trioxide-pyridine --- p.5 / Chapter 1.2.2 --- "Chromium Trioxide-3,5-dimethylpyrazole" --- p.6 / Chapter 1.3 --- Catalytic Allylic Oxidation --- p.8 / Chapter 1.3.1 --- Homogeneous Catalysts --- p.8 / Chapter 1.3.1.1 --- Chromium Catalysts --- p.8 / Chapter 1.3.1.2 --- Iron Catalysts --- p.11 / Chapter 1.3.1.3 --- Copper Catalysts --- p.13 / Chapter 1.3.1.4 --- Palladium Catalysts --- p.14 / Chapter 1.3.1.5 --- Rhodium Catalysts --- p.19 / Chapter 1.3.2 --- Heterogeneous Catalysts --- p.22 / Chapter 1.4 --- Manganese(III) Acetate --- p.24 / Chapter 1.5 --- General Application of Manganese(III) Acetate --- p.25 / Chapter 1.5.1 --- Oxidative Free Radical Cyclization --- p.25 / Chapter 1.5.2 --- α-Acetoxylation --- p.27 / Chapter 1.6 --- Manganese(III) Catalyzed Reactions --- p.28 / Chapter 1.6.1 --- Epoxidation --- p.28 / Chapter 1.6.2 --- Sulfur oxidation --- p.29 / Chapter 2. --- Results and Discussions --- p.31 / Chapter 2.1 --- The Scope --- p.31 / Chapter 2.2 --- Tuning of Reaction Conditions --- p.32 / Chapter 2.2.1 --- Variation of Oxidant --- p.32 / Chapter 2.2.2 --- Variation of the Amount of Oxidant and Catalyst --- p.34 / Chapter 2.2.3 --- Variation of Solvent --- p.36 / Chapter 2.3 --- Results of Allylic Oxidation under Optimized Conditions --- p.39 / Chapter 2.4 --- Modification of Manganese(III) Acetate Catalysed Allylic Oxidation --- p.46 / Chapter 2.4.1 --- By Adding Base --- p.46 / Chapter 2.4.2 --- Assistance by Oxygen --- p.49 / Chapter 2.5 --- Mechanism --- p.53 / Chapter 3. --- Conclusion --- p.60 / Chapter 4. --- Experimental Section --- p.62 / Chapter 5. --- References --- p.79 / Chapter 6. --- Appendix --- p.85
205

Synthetic and structural studies of organolanthanide compounds. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Chapter 1 presents an overview of the lanthanide chemistry with cyclopentadienyl and cyclopentadienyl-free ligands. The chemistry of divalent lanthanide is also briefly reviewed. / Chapter 2 describes the preparation and characterization of a series of lanthanide(III) amides derived from the bidentate 2-pyridyl amido ligand [N(SiMe3)(2-C5H3 N-6-Me)] (L 1): [Ln(L1)3] [L1=, Ln = Yb (7), Sm (8), Dy (9)], [Ln(L 1)3(THF)] [Ln = Pr (10), Gd (11)], and [(L1)2Ln(mu-OBut) 2Li(THF)x] (x = 2, Ln = Nd (12), Sm ( 13), Eu (14); x = 1, Ln = Dy (15), Er ( 16)). / Chapter 3 describes the preparation and characterization of divalent lanthanide amides derived from L1 and the more bulky [N(SiButMe2)(2-C5H 3 N-6-Me)] (L2) ligands, namely [Ln(Ln) 2(tmeda)] (n = 1, Ln = Yb (17), Eu (20); n = 2, Ln = Yb (18)), [(L1)3YbK(THF)] (19), and [(L2)3EuK(tmeda)] ( 21). Complexes 17-21 were prepared by direction reaction of LnI2(THF)), (Ln = Eu or Yb) with the potassium salts of L 1 and L2. Attempts to synthesize the analogous Sm(II) and Dy(II) derivatives were unsuccessful. The divalent samarocene, [(C 5H3(SiMe3)2)2Sm(THF)] ( 24), was also prepared in our work. Subsequent reaction of 24 with 1,3-dicyclocarbodiimide (DCC) in THF yielded the dinuclear Sm(III) bisamidinate compound [(Cp")2Sm(NC6H11) 2CC(H11C6N)2Sm(Cp")2] ( 25). / Chapter 4 describes the preparation and characterization of divalent Sm, Eu and Yb complexes derived from the bulky dianionic [R 2Si(NC6H3Pri2-2,6) 2]2- (R = Me or Ph) ligands. Treatment of LnI2(THF)), (Ln = Sm, Eu, and Yb) with K2(Ln)(THF) x (L3 = Me2Si(NC6H3Pr i2-2,6)2, L4 = Ph2Si(NC 6H3Pri2-2,6)2) afforded the corresponding Ln(II) derivatives, [(L4)2Sm{K(OEt 2)}2] (36), [(C)2Ln {K(THF) 2}2] (n = 4, Ln = Yb (39); n = 3, Ln = Sm ( 37), Yb (40), Eu (44), and the mononuclear compound [(L4)Yb(THF)3] (38). / However, attempts to prepare divalent Nd and Dy complexes of the dianionic ligands were unsuccessful. Only the corresponding Nd(III) and Dy(III) complexes were isolated. In our studies, five lanthanide(III) complexes, namely [{K(THF) 6}Ln(L4)2] (Ln = Sm (34), Yb (41), Nd (42), Dy (43)) and [(L 3)2SmK(THF)3] (35) were isolated. / This thesis describes the synthetic and structural studies of lanthanide complexes derived from the monoanionic 2-pyridyl amido ligands [N(R)(2-C 5H3N-6-Me)]- (R = SiMe3, SiBu tMe2), the dianionic [R2Si(NC 6H3 Pri2-2,O2] 2- (R = Me or Ph) ligands, and the bis(trimethylsilyl)-cyclopentadienyl [C5H3(SiMe3)2]- ligand. / Pan, Chengling. / "February 2008." / Source: Dissertation Abstracts International, Volume: 70-03, Section: B, page: 1665. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / 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.
206

Synthesis and catalytic properties of chiral amphiphilic dendritic organocatalysts. / CUHK electronic theses & dissertations collection

January 2008 (has links)
Several series of amphiphilic dendritic organocatalysts 100--112 containing an optically active, polar proline-derived core, bearing [G1]--[G3] nonpolar hydrocarbon dendrons were synthesized by a convergent approach. These compounds were characterized by NMR spectroscopy, mass spectrometry, elemental analysis and size exclusion chromatographic analysis. Such proline-based organocatalysts have been found to give products in high enantioselectivities in asymmetric aldol reactions and Michael additions in emulsion systems. The incorporation of hydrophobic dendrons in our catalyst has the advantages of promoting emulsion formation in water, enhancing the reactivity and selectivity of the asymmetric reactions, and facilitating catalyst recovery after the reactions. / This thesis describes the syntheses of chiral amphiphilic dendritic organocatalysts and their catalytic applications in asymmetric aldol reactions, Michael additions, and Mannich reactions. / Lo, Chui Man. / Adviser: Hak-Fun Chow. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3511. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 158-179). / 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.
207

Synthetic studies of carbocycles from carbohydrates. / CUHK electronic theses & dissertations collection

January 2008 (has links)
An enone was synthesized from delta-D-gluconolactone in four steps, involving a one-pot TPAP oxidation-K2CO3-mediated intramolecular Horner-Wadsworth-Emmons (HWE) olefination as the key step. / In this thesis, a review regarding intramolecular direct aldol reaction from 1971 to 2008 is presented. The background information on pseudo-acarviosin, valiolamine and its containing compounds, gabosines and human glutathione transferase (hGST) is introduced. / Intramolecular direct aldol reaction was investigated for the construction of cyclohexanones and cycloheptanones from carbohydrates. Amine bases, amide bases and L-proline were employed to facilitate cyclization of 1,5- and 1,6-diketones successfully. These 1,5- and 1,6-diketones were prepared from carbohydrates by standard transformations. Different bases were employed to promote cyclization of 1,5-diketone derived from D-glucose to give cyclohexanones stereoselectively. / Intramolecular nitrile oxide-alkene cycloaddition (INOC) was studied with sugar derivatives having free hydroxyl groups. The INOC reaction, by incorporating chloramine-T and silica gel for the formation of nitrile oxide from oxime, proceeded smoothly with one, two, and four unmasked hydroxyl groups to give cyclopentanes and cyclohexanes. / The polyhydroxylated carbocycles constructed from sugars were successfully transformed into a variety of target molecules including pseudo-acarviosin, valiolamine and its containing compounds and gabosines. A series of 2-crotonyloxymethyl-(4 R,5R,6R)-4,5,6-trihydroxy-2-cyclohexenone (COTC) analogues as inhibitors of hGST were prepared in order to study the structure-activity relationships. / Cheng, Hau Man. / Adviser: Tony K. M. Shing. / Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3508. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 214-224). / 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.
208

Mechanistic studies of bond activations by rhodium porphyrin radical and silicon-hydrogen bond activation by Rh(III) porphyrins. / CUHK electronic theses & dissertations collection

January 2006 (has links)
by Zhang Lirong. / "September 2006." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references. / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese.
209

Synthetic studies on zoapatanol.

January 1998 (has links)
by Yip Ting. / Thesis submitted in 1997. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1998. / Includes bibliographical references (leaves 55-59). / Abstract also in Chinese. / Acknowledgment --- p.i / Table of Contents --- p.ii / Abstract --- p.iii / Abbreviation --- p.iv / Chapter Part 1 --- Introduction --- p.1 / Chapter 1.1 --- General Background --- p.1 / Chapter 1.2 --- Review on the Published Syntheses of Zoapatanol --- p.2 / Chapter Part 2 --- Results and Discussion --- p.12 / Chapter 2.1 --- Synthetic Strategy --- p.12 / Chapter 2.1.1 --- Synthesis of Tertiary Alcohol46 --- p.14 / Chapter 2.1.2 --- Synthesis of Vinyl Bromide 55-Z --- p.15 / Chapter 2.1.3 --- Synthetic studies on39 --- p.18 / Chapter 2.1.4 --- Synthetic studies on40 --- p.19 / Chapter 2.2 --- Synthetic Strategy --- p.23 / Chapter 2.2.1 --- Synthesis of 79 - route1 --- p.24 / Chapter 2.2.2 --- Synthesis of 79 - route2 --- p.26 / Chapter 2.2.3 --- Synthesis of 79 - route3 --- p.28 / Chapter 2.2.4 --- Synthetic studies on free radical cyclization of79 --- p.30 / Chapter 2.2.5 --- Synthesis of83 --- p.31 / Chapter 2.2.6 --- Synthetic studies on carbanion cyclization of83 --- p.31 / Chapter Part 3 --- Conclusion --- p.33 / Chapter Part 4 --- Experimental --- p.34 / Chapter Part 5 --- References --- p.55
210

Construction of carbocycles from carbohydrates via 1,3-dipolar cycloadditions.

January 2007 (has links)
Kwok, Wun Sang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 147-152). / Abstracts in English and Chinese. / Acknowledgment --- p.i / Table of Contents --- p.ii / Abstract --- p.iii / Abstract (Chinese Version) --- p.iv / Abbreviation --- p.v / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- General Background --- p.1 / Chapter 1.1.1 --- "1,3-Dipolar Cycloaddition" --- p.1 / Chapter 1.1.2 --- Structure of Preparation of Nitrile Oxide --- p.3 / Chapter 1.2 --- Intramolecular Nitrile Oxide Alkene Cyclization (INOC) --- p.7 / Chapter 1.2.1 --- INOC in Organic Synthesis --- p.7 / Chapter 1.2.2 --- Formation of Oximolactone as Unwanted Reaction in INOC --- p.10 / Chapter 1.2.3 --- Nitrile Oxide Alkene Cyclization with Free Hydroxyl Group --- p.11 / Chapter 1.3 --- Natural Occurring Gabosine --- p.14 / Chapter 1.3.1 --- "Structure, Biological Effect and Syntheses of Gabosines" --- p.14 / Chapter 1.3.2 --- Synthesis of Gabosine O and its 4-epimer --- p.17 / Chapter 1.4 --- Protected 6-dehydroxy-Pseudo-a-D-Talose --- p.21 / Chapter 1.4.1 --- Structures and Biological Effects of Valienamine and its Derivatives --- p.21 / Chapter 1.4.2 --- Structural and Biological Studies of Valienamine by Our Group --- p.23 / Chapter 2. --- Results and Discussion --- p.28 / Chapter 2.1 --- Studies on INOC of Sugar Derivatives with Free Hydroxyl Group(s) --- p.28 / Chapter 2.2 --- Enantiospecific Synthesis of 4-epi-Gabosine O --- p.47 / Chapter 2.3 --- Enantiospecific Synthesis of Gabosine O --- p.84 / Chapter 2.4 --- Synthesis of 6-Deoxy-Pseudo-a-D-Talose --- p.87 / Chapter 3. --- Conclusion --- p.95 / Chapter 4. --- Experimental --- p.100 / References --- p.147 / Appendix NMR spectra --- p.153

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