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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.
71

Synthesis and studies of 1,4,5,8,9,12,13,16-octahydroxytetraphenylene.

January 2003 (has links)
by Chun Wing Lai. / Thesis submitted in: August 2002. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 87-92). / Abstracts in English and Chinese. / ACKNOWLEDMENTS --- p.1 / CONTENTS --- p.2 / ABTRACT --- p.5 / Chapter CHAPTER 1 --- INTRODUCTION --- p.7 / Chapter 1.1 --- General background --- p.7 / Chapter 1.2 --- Synthesis of tetraphenylene and its derivatives --- p.8 / Chapter 1.2.1 --- From electrophililc aromatic substitution --- p.9 / Chapter 1.2.2 --- From biphenylene pyrolysis --- p.10 / Chapter 1.2.3 --- From aryl halide coupling --- p.13 / Chapter 1.2.4 --- From bis-acetylene --- p.15 / Chapter 1.2.5 --- Synthesis of tetraphenylenes fused with carbocycles and heterocycles --- p.17 / Chapter 1.3 --- Inversion barrier of tetraphenylenes --- p.21 / Chapter 1.4 --- Clathrate inclusion properties of tetraphenylene and its derivatives --- p.27 / Chapter 1.5 --- Tetraphenylenols --- p.33 / Chapter CHAPTER 2 --- RESULTS AND DISCUSSION / Chapter 2.1 --- Aim of the present work --- p.38 / Chapter 2.2 --- "Retrosynthetic studies on 1,4,5,8,9,12,13,16-octahydroxytetraphenylene" --- p.39 / Chapter 2.2.1 --- "1,4,5,8-tetramethoxybiphenylene approach" --- p.39 / Chapter 2.2.2 --- "2,2'-diiodo-3,3',6,6'-tetramethoxybiphenyl approach" --- p.42 / Chapter 2.3 --- "Preparation of 1,4,5,8-tetramethoxybiphenylene" --- p.44 / Chapter 2.3.1 --- "From 2-amino-3,6-dimethoxybenzoic acid" --- p.44 / Chapter 2.3.2 --- "From l-amino-4,7-dimethoxybenzotriazole" --- p.47 / Chapter 2.4 --- "Synthesis of 1,4,5,8,9,12,13,16-octamethoxytetraphenylene from 1,4,5,8-tetramethoxybiphenylene" --- p.50 / Chapter 2.5 --- "Synthesis of 2,2'-diiodo-3,3',6,6'-tetramethoxybiphenyl" --- p.51 / Chapter 2.6. --- "Synthesis of 1,4,5,8,9,12,13,16-octamethoxytetraphenylene from 2,2,-diiodo-3,3 ',6,6' -tetramethoxybiphenyl" --- p.53 / Chapter 2.7 --- Synthesis of other tetraphenylene derivatives --- p.57 / Chapter 2.8 --- X-ray crystallographic studies of tetraphenylene derivatives --- p.59 / Chapter 2.8.1 --- "X-ray crystallographic studies of 1,4,5,8,9,12,13,16-octamethoxytetraphenylene" --- p.59 / Chapter 2.8.2 --- "X-Ray crystallographic studies of 1,4,5,8,9,12,13,16-octahydroxytetraphenylene" --- p.61 / Chapter 2.9 --- "Electrochemical properties of 1,4,5,8,9,12,13,16-octamethoxytetraphenylene and l,4,5,8,9,12,13,16-octahydro-l,4,5,8,9,12,13,16-octaoxo- tetraphenylene" --- p.62 / Chapter 2.9.1 --- "Electrochemical properties of 1,4,5,8,9,12,13,16-octamethoxytetraphenylene" --- p.65 / Chapter 2.9.2 --- "Electrochemical properties of 1,4,5,8,9,12,13,16-octahydro-1,4,5,8,9,12,13,16-octaoxo- tetraphenylene" --- p.66 / Chapter CHAPTER 3 --- CONCLUSION --- p.69 / Chapter CHAPTER 4 --- EXPERIMENTAL SECTION --- p.70 / REFERENCES --- p.87 / APPENDICES --- p.93 / Chapter I. --- List of NMR spectra --- p.95 / Chapter II. --- List of cyclic voltammetric data --- p.109 / Chapter III. --- List of X-ray crystallographic data --- p.111
72

Synthesis and studies of 1,4,5,16-tetrasubstituted tetraphenylenes.

January 2008 (has links)
Yang, Bi Bo. / Thesis submitted in: October 2007. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references (leaves 58-64). / Abstracts in English and Chinese. / ABSTRACT --- p.iii / ABBREVIATIONS --- p.vi / INTRODUCTION --- p.1 / Chapter 1.1 --- General background --- p.1 / Chapter 1.1.1 --- Cyclooctatetraene --- p.1 / Chapter 1.1.2 --- Benzannelated cyclooctatetraenes --- p.2 / Chapter 1.1.3 --- Cyclooctatrienyne --- p.4 / Chapter 1.1.4 --- Benzannelated cyclooctatrienynes --- p.4 / Chapter 1.2 --- "Tetrabenzo[a,c,e,g]cyclooctatetraene (tetraphenylene) (1)" --- p.7 / Chapter 1.2.1 --- Ring inversion barrier of tetraphenylenes --- p.8 / Chapter 1.2.2 --- Inclusion properties of tetraphenylenes --- p.9 / Chapter 1.3 --- Synthetic methods for tetraphenylene (1) and its derivatives --- p.10 / Chapter 1.3.1 --- Electrophilic aromatic substitution on tetraphenylenes --- p.10 / Chapter 1.3.2 --- Diels-Alder reactions of cyclooctadienediyne --- p.11 / Chapter 1.3.3 --- Pyrolysis of biphenylene --- p.12 / Chapter 1.3.4 --- Transition metal complexes-promoted ring expansion-dimerization of biphenylene --- p.13 / Chapter 1.3.5 --- "Coupling of 2,2'-dihalobiphenyls" --- p.14 / Chapter 1.4 --- Applications of tetraphenylene derivatives as functional materials --- p.17 / Chapter 1.4.1 --- Tetraphenylene derivatives employed as molecular devices --- p.17 / Chapter 1.4.2 --- Tetraphenylene derivatives employed as building blocks for liquid crystals --- p.18 / Chapter 1.5 --- Tetraphenylenols as building blocks for molecular scaffolds --- p.18 / RESULTS AND DISCUSSION --- p.23 / Chapter 2.1 --- "Synthesis of 1,4,5,16-tetrahydroxytetraphenylene (68)" --- p.23 / Chapter 2.1.1 --- "Preparation of 1,10-dimethoxydibenzo[a,e]cyclooctene (82)" --- p.25 / Chapter 2.1.2 --- "Preparation of 1,12-dimethoxytribenzo[a,c,e]cyclooctene (97)" --- p.28 / Chapter 2.1.3 --- "Preparation of 1,4-endoxo-1,4-dihydro-5,l6- dimethoxytetraphenylene (81)" --- p.31 / Chapter 2.1.4 --- "Preparation of 1,4,5,16-tetrahydroxytetraphenylene (68)" --- p.33 / Chapter 2.2 --- Molecular scaffold consisting of tetraphenylenol 68 and (S)-(BINAP)PtC03 --- p.36 / Chapter 2.3 --- "Preparation of 1,4,5,16-tetracyanotetraphenylene (77)" --- p.37 / CONCLUSION --- p.40 / EXPERIMENTAL --- p.41 / REFERENCES --- p.58 / APPENDICES --- p.65
73

(Rh(CO)₂Cl)₂-catalyzed allylic substitution reactions and domino sequences and application of the Pauson-Khand reaction to the synthesis of azabicyclic structures total synthesis of (-)-alstonerine /

Miller, Kenneth Aaron, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
74

Determinants of currency substitution and money demand in the Russian Federation /

Yang, Steve S., January 2001 (has links)
Thesis (Ph. D.)--University of Washington, 2001. / Vita. Includes bibliographical references (leaves 185-190).
75

Influence of the nephelauxetic effect on the kinetic and thermodynamic stability of cobalt (III) complexes of the tetramine type.

Tong, Ha-wai. January 1973 (has links)
Thesis Ph. D., University of Hong Kong. / Includes reprints of 2 papers entitled Structural and mechanistic studies of co-ordination compounds. Part II ... by C.K. Poon and H.W. Tong, from the Journal of the Chemical Society (A), 1971, and Structural and mechanistic studies of co-ordination compounds. Part V ... by K.S. Mok and others, from the Journal of the Chemical Society (Dalton), 1972.
76

The kinetics and mechanism of substitution in some cobalt (III) complexes.

Leung, Ping-yuen. January 1969 (has links)
Thesis (M. Sc.)--University of Hong Kong, 1970. / Typewritten.
77

The transmission of substituent effects in phosphonitrilics.

Leung, Chung-pui. January 1969 (has links)
Thesis--Ph. D., University of Hong Kong. / Typewritten.
78

Synthetic studies of N-heterocycles via catalytic reductive C-C bond formation and tertiary neopentyl substitution / Synthetic studies of N-heterocycles via catalytic reductive C-C bond coupling and tertiary neopentyl substitution

Grant, Christopher Donald 06 July 2012 (has links)
Whilst there are a large number of C-C bond forming reactions available for the construction of heterocycles a number of these protocols require the use of stoichiometric organometallic reagents. Since heterocycles are present in the vast majority of pharmaceutical agents the ability to forge these structures efficiently with a minimal amount of stoichiometric metallic waste is important. With this in mind we initiated a series of projects that focus on the use of [pi]-unsaturates to serve as surrogates to toxic, air and moisture sensitive nucleophilic organometallic reagents utilized in traditional C-C bond forming reactions. This has allowed us to develop catalytic couplings of vinyl azines to imines to form branched amines, to couplings of dimethylallene to isatin forming a tert-prenyl hydroxy oxindole and this neopentyl alcohol can be substituted with C-nucleophiles forming two contiguous quaternary all-carbon centers in our synthetic studies tert-prenyl indole alkaloid natural products. / text
79

Synthesis of cyclic trisubstituted olefinic monomers for copolymerization and 2+2 cycloaddition

Wai, George Kwok Cheung, 1949- January 1976 (has links)
No description available.
80

An investigation of the effect of benzene substitution pattern on the formation of discotic phases

Chau, Sotheary 12 1900 (has links)
No description available.

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