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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.
91

Some studies on transition metal alkyl complexes

Hawthorne, John Duncan January 1969 (has links)
No description available.
92

EXPLORING THE LIVED EXPERIENCE OF THE POST 9-11 ARMY VETERAN IN TRANSITION: TOWARD A THEORETICAL FRAMEWORK

DeGroat, Arthur S. January 1900 (has links)
Doctor of Education / Department of Educational Leadership / W. Franklin Spikes / This exploratory study applies lived experience phenomenological theory from the human science academic literature to understand the nature of Post 9-11 era Army veteran’s transition experience to life and work after the military. The purpose of this study was to determine the original meaning of this unique life event of transition of contemporary Army veterans. Also, this study sought to develop a better understanding of possible ways in which this life event of transitioning can be enhanced. Using primary data from in-depth, semi-structured interviews with eight Army veterans in transition, a structural analysis was performed to identify original meaning structures and a narrative description of this human life event. Findings from this study indicate that five original themes exist that convey the original meaning of this phenomenon. Post 9-11 Army veterans’ transition was found to be a situated and dynamic life event which affects one’s mobility to cross boundaries from military to civilian life. It is a socially mediated effort that involves reconstruction of personal identity through the process of self-realization and reformation or non-formation of one’s personal mindset and socialization to form new social bonds.
93

The synthesis and characterization of macrocyclic ligands and investigations of the thermo and photo reactivity of their transition metal ion complexes

Mackay, Ian Douglas 28 June 2017 (has links)
The mono protection of 1,4,7-triazacyclononane ([9]-aneN₃) was accomplished efficiently through the formation of an orthoamide derivative. The orthoamide was used to form three mono protected derivatives of [9]-aneN₃ which contained either a formyl, methyl, or benzyl protecting group attached to one of the nitrogen donors. The macrobicyclic complexes bicycloN₅, Me-bicycloN₅, and Bz-bicycloN₅ were synthesized through the Michael addition of two functional arms to the mono protected derivatives of [9]-aneN₃ followed by a ring closure template reaction around copper with glyoxal. Incomplete reduction by BH₃ THF led to the isolation of an enamine intermediate. The solution behavior o f the Ni(II) and Ni(III) complexes of these macrobicyclic ligands is presented. The methyl and benzyl derivatives were found to have similar abilities as the parent bicycloN₅ ligand to stabilize the Ni(III) metal ion. Removal of the benzyl protecting group was achieved by reaction with formic acid in the presence of a Pd/C catalyst. Attempts to couple two mono protected nonane molecules through the addition of functional acid chloride arms under conditions of high dilution were unsuccessful. Reaction of the benzyl protected bicyclic ligand Bz-bicycloN₅ with a bridging ligand in a high dilution reaction did provide evidence for the formation of a small amount of the novel macrotricyclic ligand tricyclo[9.14.9]N₆. The Ni(II) complexes of the macrobicyclic ligands, and a series of other macrocyclic and related Ni(II) complexes having varying NiIII/II redox potentials, were used to study the quenching of the excited state of the platinum(II) dimeric complex Pt₂(pop)₄⁴− . The quenching rate constants kq were determined, and quenching of the excited state *Pt₂(pop)₄⁴− by the nickel complexes was found to proceed by reductive electron transfer. These results are discussed in terms of Marcus Theory. A plot of logkq versus the ΔG for electron transfer was found to exhibit classic Rehm- Weller behavior. The excited state potential Pt₂(pop)₄⁴⁻*/⁵- was estimated from this series of quenching reactions and a range of 1.24 to 1.34 V (vs. NHE) was identified. The photochemical and photophysical properties of the macrocyclic complex Cr([18]-aneN₆)³+ ([18]-aneN₆ = 1,4,7,10,13,16-hexaazacyclooctadecane) were investigated and compared to the properties of the photoreactive Cr(III) complex Cr(sen)³+ (sen = 4,4',4"-ethylidynetris(3-azabutan-l-amine)). The complex Cr([18]- aneN₆)³+ was found to be unreactive (Ørxn < 10⁻³) while the photoreactivity of Cr(sen)³+ was confirmed (Ørxn = 0.10). Both of these complexes have very short ambient ²E emission lifetimes and this is discussed in terms of distortions imposed on the complexes by the coordination of the ligands. Direct irradiation into the doublet excited state of Cr(sen)3⁺ at 675 nm resulted in a decrease in the quantum yield for the photoreaction of this complex from Ørxn=0.10 for quartet irradiation to Ørxn=0.08 for doublet irradiation. A model is suggested in which there are two competitive processes deactivating the doublet excited state; reverse intersystem crossing to the lowest quartet excited state and nonradiative decay back to the ground state. The temperature dependence of the ²E emission lifetime was fitted to a two-term Arrhenius function to give estimates for the pre-exponential factors and activation energies of these two deactivation processes. Values of A₁ = (1.2 ± 0.9) x 1O¹⁵ s⁻¹ and Eₐ₁ = 45 ± 1 kJ mol⁻¹,and A₂ = (5.4 ± 1.2) x 10¹¹s⁻¹ and Eₐ2 = 29 ± 1 kJ mol⁻¹ were obtained. The photostereochemistry of Cr(sen)³⁺ was investigated using a modified reversed phase HPLC technique. A total of four photoproducts were identified from the photolysis of the resolved stereoisomers of Cr(sen)³⁺ and a loss of optical activity was found to be associated with the photoreaction. These results are discussed in terms of current models for predicting photostereoreactivity of Cr(III) complexes. / Graduate
94

A new perspective on the jamming transition: geometry reveals hidden symmetries

Morse, Peter 27 October 2016 (has links)
Jamming is a physical process which is both easy to describe and incredibly difficult to understand. One such difficulty is that mechanical treatments of jamming focus on pressure, force, stress, and strain, which are identically zero below jamming, making it hard to differentiate systems whcih which are near or far from the transition. Instead, I introduce a geometric framework based on the Voronoi tesselation which treats all of phase space on an equal footing. This work will show that the jamming transition can be seen entirely through the geometry of the local environment of particles encoded in the Voronoi tesselation, and it will build the framework for an as yet undefined field theory for jamming.
95

The chemistry of low-valent late transition metal amides and amidinates.

January 2002 (has links)
by Tung Suet Lam. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references. / Abstracts in English and Chinese. / Table of Contents --- p.i / Acknowledgments --- p.iv / Abstract --- p.v / Abstract (Chinese version) --- p.vii / Abbreviations --- p.ix / List of Compounds --- p.xi / Chapter Chapter1. --- synthesis and structures of iron(ii) and cobalt(ii) complexes derived from pyridine-functionalized amido ligands / Chapter 1.1 --- INTRODUCTION --- p.1 / Chapter 1.1.1 --- General Background --- p.1 / Chapter 1.1.2 --- A Brief Review on Amides of the Late Transition Metals --- p.3 / Chapter 1.2 --- OBJECTIVES OF THIS WORK --- p.5 / Chapter 1.3 --- RESULTS AND DISCUSSION --- p.7 / Chapter 1.3.1 --- Alkali Metal Derivatives of N-Silylated 2-Aminopyridines --- p.7 / Chapter 1.3.1.a. --- "Synthesis of Aminopyridines [HN(SiMe3)》(2-C5H3N-6-R)] (R=H (1a), Me (1b)) and Their Lithium Derivatives" --- p.7 / Chapter 1.3.1.b. --- Synthesis of the Potassium Derivative [{K(L1)(tmeda)}2 ] (4) --- p.8 / Chapter 1.3.1.c. --- "Physical Characterization of Compounds 2a, 3 and" --- p.4 9 / Chapter 1.3.1.d. --- Molecular Structures of Compounds 3 and4 --- p.10 / Chapter 1.3.2 --- "Synthesis, Structures and Reactivities of Iron(II) and Cobalt(II) Amides" --- p.16 / Chapter 1.3.2.a. --- Synthesis of Mononuclear Iron(II) and Cobalt(II) Diamides --- p.16 / Chapter 1.3.2.b. --- Physical Characterization of Compounds 5-8 --- p.16 / Chapter 1.3.2.C. --- Molecular Structures of Compounds 5-8 --- p.17 / Chapter 1.4 --- EXPERIMENTAL FOR CHAPTER1 --- p.28 / Chapter 1.5 --- REFERENCES FOR CHAPTER1 --- p.31 / Chapter Chapter2. --- reaction of iron(II) and cobalt(II) amides with phenolic compounds / Chapter 2.1 --- "SYTHESIS, STRUCTURES AND REACTIVITIES OF IRON(II) AND COBALT(II) BIS(ARYLOXIDE)" --- p.36 / Chapter 2.1.a. --- "Reaction of Compounds 7 and 8 with 2,2 -ethylidenebis(4,6-di-tert-butyl phenol)" --- p.36 / Chapter 2.1.b. --- "Molecular Structures, Magnetic Moments, and Reactivities of Compounds 9and10" --- p.36 / Chapter 2.2 --- A GENERAL REVIEW ON CATECHOL DIOXYGENASES --- p.44 / Chapter 2.3 --- "SYTHESIS, STRUCTURES AND REACTIVITIES OF IRON(II) AND COBALT(II) CATECHOLATES" --- p.46 / Chapter 2.3.a. --- Synthesis of Binuclear Iron(II) and Cobalt(II) Catecholates --- p.46 / Chapter 2.3.b. --- Molecular Structures of Compounds 11 and12 --- p.48 / Chapter 2.3.c. --- Reactions of Compounds 11 and 12 with Dioxygen --- p.54 / Chapter 2.3.d. --- Identification of Oxidative Cleavage Products --- p.54 / Chapter 2.4 --- EXPERIMENTAL FOR CHAPTER2 --- p.56 / Chapter 2.5 --- REFERENCES FOR CHAPTER2 --- p.59 / Chapter Chapter3. --- synthesis of late transition metal amidinates / Chapter 3.1 --- INTRODUCTION --- p.62 / Chapter 3.1.1 --- General background --- p.62 / Chapter 3.1.1.a --- Metal´ؤAmidine Bonding Modes --- p.63 / Chapter 3.1.1.b. --- Preparation of Metal Amidinates Complexes --- p.64 / Chapter 3.1.2 --- "N-Silylated Benzamidinates of Li, Na and K 一 The Starting Materials" --- p.65 / Chapter 3.1.3 --- A General Review on The Chemistry of Low-Valent Late Transition- Metal Amidinates --- p.67 / Chapter 3.2 --- OBJECTIVES OF THIS WORK --- p.72 / Chapter 3.3 --- RESULTS AND DISCUSSION --- p.73 / Chapter 3.3.1 --- Synthesis and Structures of Lithium Benzamidinates --- p.73 / Chapter 3.3.1.a. --- "Synthesis of [Li(L3)(tmeda)] (L3 = [PhC(NSiMe3){N(2,6´ؤ Me2C6H3}]) and [Li(L4)(tmeda)] (L4 = [PyC(NSiMe3){N(2,6- Me2C6H3)}]) as Ligand´ؤTransfer Reagents" --- p.73 / Chapter 3.3.1.b. --- Physical Characterization of Compounds 15 and16 --- p.74 / Chapter 3.3.1.c. --- Molecular Structures of Compounds 15 and16 --- p.75 / Chapter 3.3.2 --- "Synthesis, Structures and Reactivities of Iron(II) and Cobalt(II) Amidinates" --- p.81 / Chapter 3.3.2.a. --- Synthesis of Mononuclear Iron(II) Benzamidinates --- p.81 / Chapter 3.3.2.b. --- Synthesis of a Binuclear Cobalt(II) Benzamidinate --- p.82 / Chapter 3.3.2.c. --- Physical Characterization of Compounds 17-19 --- p.83 / Chapter 3.3.2.d. --- Molecular Structures of Compounds 17-19 --- p.84 / Chapter 3.3.2.e. --- Reaction of Compound 18 with Dioxygen --- p.94 / Chapter 3.3.2.f. --- Molecular Structure of Compound20 --- p.95 / Chapter 3.3.3 --- Synthesis and Structures of Nickel(II) and Copper(I) Benzamidinates --- p.98 / Chapter 3.3.3.a --- Synthesis of a Nickel(II) Benzamidinate --- p.98 / Chapter 3.3.3.b. --- Synthesis of a Binuclear Copper(I) Benzamidinate --- p.99 / Chapter 3.3.3.c. --- Physical Characterization of Compounds 21 and22 --- p.101 / Chapter 3.3.3.d. --- Molecular Structures of Compounds 21 and22 --- p.102 / Chapter 3.3.4 --- Synthesis and Structures of Mononuclear Zinc(II) and Cadmium(II) Amidinates --- p.107 / Chapter 3.3.4.a --- Synthesis of Mononuclear Zinc(II) and Cadmium(II) Benzamidinates --- p.107 / Chapter 3.3.4.b. --- Physical Characterization of Compounds 23 and24 --- p.107 / Chapter 3.3.4.C. --- Molecular Structures of Compounds 23 and24 --- p.108 / Chapter 3.4 --- EXPERIMENTAL FOR CHAPTER3 --- p.113 / Chapter 3.5 --- REFERENCES FOR CHAPTER3 --- p.119 / appendix1 --- p.127 / appendix2 --- p.129
96

Synthetic and structural studies of groups 4-6 transition metal amides and amidinates.

January 2007 (has links)
Lam, Pui Chi. / Thesis submitted in: November 2006. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references. / Abstracts in English and Chinese. / Table of Contents --- p.i / Acknowledgements --- p.v / Abstract --- p.vi / 摘要 --- p.viii / List of Compounds --- p.x / Abbreviations --- p.xiii / Chapter CHAPTER 1. --- A GENERAL INTRODUCTION TO METAL AMIDES / Chapter 1.1 --- GENERAL BACKGROUND --- p.1 / Chapter 1.2 --- OBJECTIVES OF THIS WORK --- p.7 / Chapter 1.3 --- REFERENCES FOR CHAPTER1 --- p.8 / Chapter CHAPTER 2. --- SYNTHESIS AND STRUCTURES OF GROUP 4 METAL AMIDES / Chapter 2.1 --- INTRODUCTION --- p.15 / Chapter 2.1.1 --- General Background --- p.15 / Chapter 2.1.2 --- Common Preparation Methods for Group 4 Metal Amides --- p.15 / Chapter 2.1.3 --- "An Overview on Titanium(IV), Zirconium(IV) and Hafnium(IV) Amides" --- p.17 / Chapter 2.2 --- AIMS OF OUR STUDIES --- p.26 / Chapter 2.3 --- RESULTS AND DISCUSSION --- p.27 / Chapter 2.3.1 --- Synthesis of the Ligand Precursor (HL1) and the Corresponding Lithium Derivative [Li(L1tmeda)] --- p.27 / Chapter 2.3.2 --- Synthesis and Structures of Monomeric and Dimeric Titanium(IV) Amides --- p.28 / Chapter 2.3.2.1 --- Synthesis of [Ti(L1 )Cl2(μ-Cl)2] (V and [TiL1)Ch3(THF)] (4) --- p.28 / Chapter 2.3.2.2 --- Reactivity Studies --- p.31 / Chapter 2.3.2.3 --- Physical Characterization of Compounds 3 and 4 --- p.33 / Chapter 2.3.2.4 --- Molecular Structures of Compounds 3 and 4 --- p.36 / Chapter 2.3.3 --- Synthesis and Structures of Mononuclear Zirconium(IV) and Hafnium(IV) Amides --- p.44 / Chapter 2.3.3.1 --- Synthesis of[M(L1)3Cl] (M = Zr 5 and Hf6) --- p.44 / Chapter 2.3.3.2 --- Reactivity Studies --- p.45 / Chapter 2.3.3.3 --- Synthesis of[MCL1)3H] (M = Zr7 and Hf8) --- p.48 / Chapter 2.3.3.4 --- Reactivity Studies of Compound7 --- p.49 / Chapter 2.3.3.5 --- Physical Characterization of Compound 8 --- p.51 / Chapter 2.3.3.6 --- Molecular Structures of Compound 8 --- p.53 / Chapter 2.3.3.7 --- Synthesis of [Zr(L1)3Me] (9) --- p.57 / Chapter 2.3.3.8 --- Reactivity Studies of Compound 9 --- p.58 / Chapter 2.3.3.9 --- Physical Characterization of Compound 9 --- p.59 / Chapter 2.3.3.10 --- Molecular Structure of Compound 9 --- p.60 / Chapter 2.4 --- EXPERIMENTALS FOR CHAPTER 2 --- p.64 / Chapter 2.4.1 --- General Procedures --- p.64 / Chapter 2.4.2 --- Synthesis of Compounds --- p.65 / REFERENCES FOR CHAPTER 2 --- p.68 / Chapter CHAPTER 3. --- SYNTHESIS AND STRUCTURES OF VANADIUM(III) AMIDO AND BENZAMIDINATO COMPLEXES / Chapter 3.1 --- INTRODUCTION --- p.74 / Chapter 3.1.1 --- General Background --- p.74 / Chapter 3.1.2 --- A Brief Introduction on Metal Amidinates --- p.75 / Chapter 3.1.3 --- An Overview on Vanadium(III) Amides --- p.77 / Chapter 3.1.4 --- An Overview on Vanadium(III) Amidinates --- p.82 / Chapter 3.2 --- AIMS OF OUR STUDIES --- p.85 / Chapter 3.3 --- RESULTS AND DISCUSSION --- p.86 / Chapter 3.3.1 --- Synthesis and Structures of Dinuclear Vanadium(III) Amides --- p.86 / Chapter 3.3.1.1 --- Synthesis of[V(L1)2(μ~Cl)]2(10) --- p.86 / Chapter 3.3.1.2 --- Reactivity Studies --- p.88 / Chapter 3.3.1.3 --- Synthesis of [V(L1)2(μ-H)]2 (11) --- p.90 / Chapter 3.3.1.4 --- Physical Characterization of Compounds 10 and 11 --- p.90 / Chapter 3.3.1.5 --- Molecular Structures of Compounds 10 and 11 --- p.94 / Chapter 3.3.2 --- Synthesis and Structure of Mononuclear Vanadium(III) Benzamidinate --- p.102 / Chapter 3.3.2.1 --- "Synthesis of [Li(L2)(tmeda)] (13) (L2 = [PhC(NSiMe3) (NC6H3Me2-2, 6)])" --- p.102 / Chapter 3.3.2.2 --- Synthesis of [V(L2)2Cl] (14) and trans´ؤ[V(tmeda)2Cl2] (15) --- p.103 / Chapter 3.3.2.3 --- Reactivity Studies --- p.104 / Chapter 3.3.2.4 --- Physical Characterization of Compound 14 --- p.107 / Chapter 3.3.2.5 --- Molecular Structure of Compound 14 --- p.107 / Chapter 3.4 --- EXPERIMENTALS FOR CHAPTER 3 --- p.111 / Chapter 3.4.1 --- General Procedures --- p.111 / Chapter 3.4.2 --- Synthesis of Compounds --- p.112 / Chapter 3.5 --- REFERENCES FOR CHAPTER 3 --- p.115 / Chapter CHAPTER 4. --- SYNTHESIS AND STRUCTURES OF CHROMIUM AMIDO AND BENZAMIDINATO COMPLEXES / Chapter 4.1 --- INTRODUCTION --- p.122 / Chapter 4.1.1 --- General Background --- p.122 / Chapter 4.1.2 --- An Overview on Chromium(III) Amides --- p.122 / Chapter 4.1.3 --- An Overview on Chromium(II) Amidinates --- p.125 / Chapter 4.2 --- AIMS OF OUR STUDIES --- p.129 / Chapter 4.3 --- RESULTS AND DISCUSSION --- p.130 / Chapter 4.3.1 --- Synthesis and Structures of A Monomeric Chromium(III) Amide and A Chromium(II) Benzamidinate --- p.130 / Chapter 4.3.1.1 --- Synthesis of[Cr(L1)3] (16) --- p.130 / Chapter 4.3.1.2 --- Synthesis of [Cr(L2)2] (17) --- p.132 / Chapter 4.3.1.3 --- Physical Characterization of Compounds 16 and 17 --- p.133 / Chapter 4.3.1.4 --- Molecular Structures of Compounds 16 and 17 --- p.135 / Chapter 4.4 --- EXPERIMENT ALS FOR CHAPTER 4 --- p.141 / Chapter 4.4.1 --- General Procedures --- p.141 / Chapter 4.4.2 --- Synthesis of Compounds --- p.141 / Chapter 4.5 --- REFERENCES FOR CHAPTER 34 --- p.144 / APPENDIX 1 / Physical Measurements and X-Ray Crystallography --- p.147 / APPENDIX 2 / "Mass Spectra, 1'H and 13C{]H} NMR Spectra, and IR Spectra" --- p.148 / APPENDIX 3 --- p.172 / Table A-1. Selected crystallographic data for compounds 3-4 --- p.173 / Table A-2. Selected crystallographic data for compounds 8-9 --- p.174 / Table A-3. Selected crystallographic data for compounds 10-11 --- p.175 / Table A-4. Selected crystallographic data for compounds 14,16-17 --- p.176
97

Att flyta till särskilt boende : Ur ett patientperspektiv

Nadira, nazmun nahar, Ali Ibrahim, Media January 2019 (has links)
Bakgrund: Att flytta från sitt eget hem till ett särskilt boende är en stor förändring för en äldre människa. Man lämnar sina vanliga rutiner och hamnar i en situation som kan upplevas svår att behärska. Man kanske inte får plats med alla sina ägodelar och många gånger kan man behöva hjälp med att äta, klä på sig och minnas saker. Ofta lämnar man även sitt sociala liv bakom sig. Syfte: Att beskriva äldre personers upplevelse av att flytta hemifrån till ett särskilt boende. Metod: En systematisk litteraturstudie har utförts, i vilken kvalitativa artiklar har analyserats. Resultat: Det framkom två teman och fyra subteman i analysen. Resultatet visade att de äldre människorna inte kände sig delaktiga och att upplevelsen inte var som förväntat. De upplevde ofta att de inte fick ta ett medansvar. Majoriteten upplevde att de var i trygga händer, vilket var en grundläggande faktor för att känna sig accepterade och trygga. Många upplevde att det som började som en negativ händelse (att flytta till särskilt boende), i slutändan löste sig till det bästa. Slutsats: Äldre människor beskriver att de kan lära sig att acceptera situationen de befinner sig i, och även uppleva att något förväntansfullt väntar dem i livet.
98

Transition metal complexes of flexible ligands containing a dipyridinylmethanone moiety. / CUHK electronic theses & dissertations collection

January 2005 (has links)
Di-2-pyridinylmethanone (di-2-pyridyl ketone) is a well-known ligand within the family of basic building blocks for the construction of metal-organic complexes with diverse architectures and potential applications in relation to their physical and chemical properties. A systematic investigation on the generation and structure of transition metal complexes based on six ligands containing the dipyridinylmethanone moiety is reported in this thesis. Although all these ligands are known except L7, their coordination chemistry remains unexplored to date. / Ligand 2-pyridinyl-3-pyridinylmethanone (L1) is an excellent building block for the construction of infinite single-strand helical architectures with various metal salts. In the resultant helical complexes, Ll exhibits three kinds of coordination modes involving two kinds of bridging conformations, resulting in four types of single-strand helical chains. Among them is a pair of helical conformational polymorphs generated by the solvent-controlled process, in which the 21 helices of opposite chirality in one are stacked alternately to form a racemate, whereas the 41 helices in the other are assembled homochirally by inter-chain argentophilic interaction to generate a conglomerate. In a series of six isostructural 21 helical Ag(I) complexes, the pitch length corresponds not only to the size of the embedded anion but also to the manner of its fitting into the groove of the helix. In the Co(II) and Zn(II) complexes that comprise helical chains without anion embedment, the pitch lengths are dictated by the size of the metal cations. / Ligand 2-pyridinyl-4-pyridinylmethanone (L2) readily gives rise to dimeric metallacyclophanes with various Ag(I) salts, which bear close structural similarity. An ordered sequence of the coordinating ability of a series of nine polyatomic monoanions has been established on the basis of structural parameters derived from their interaction with a common disilver(I) metallacyclophane skeleton in isostructural complexes. The reactions of L2 with Co(II), Cu(II), Zn(II) and Cd(II) salts give rise to supramolecular architectures assembled through weak interactions including hydrogen bonding and pi&middot;&middot;&middot;pi stacking, in which L2 adopts various ligation modes. / Metal complexes of 3-pyridinyl-4-pyridinylmethanone (L4) exhibit a variety of structural types: single chain, ladder-like chain, (4,4) network and tetrameric unit. (Abstract shortened by UMI.) / Chen Xudong. / "July 2005." / Adviser: Thomas C. W. Mak. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3787. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 143-164). / 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.
99

The development of novel enantioselective transition metal-catalysed 1,4- and 1,6-additions

Roy, Iain David January 2015 (has links)
1. ENANTIOSELECTIVE RHODIUM-CATALYSED 1,4-ARYLATION OF ALKENYLAZAARENES An extended study on the enantioselective rhodium-catalysed 1,4-arylation of alkenylazaarenes has been conducted. The 1,4-arylation of various alkenylazaarenes was performed with an extended range of arylboronic acids using a modified catalytic system with a superior chiral diene ligand. The result is the generation of a large number of b-stereocentre-containing azaarene compounds in high enantiopurity. Further studies also enabled the completion of a reactivity index between alkenylazaarenes and more traditional α,β-unsaturated carbonyl compounds and the incorporation of the arylation into arylation-aldol domino processes. 2. ENANTIOSELECTIVE RHODIUM-CATALYSED 1,4-ALKENYLATION OF ALKENYLAZAARENES An extensive study on the enantioselective rhodium-catalysed 1,4-alkenylation of alkenylazaarenes has been performed. Development of the reaction parameters identified novel heterogeneous reaction conditions in pure water with sub-stoichiometric SDS. Subsequent ligand development identified an anilide-based chiral diene that provided the best balance between conversion and enantiopurity. Using the novel conditions, a selection of alkenylazaarenes underwent enantioselective rhodium-catalysed 1,4-alkenylation with two alkenyl MIDA boronates to provide the alkenylation products in good to excellent yields and moderate to excellent enantioselectivities. 3. ENANTIOSELECTIVE COPPER-CATALYSED 1,6-BORATION OF ELECTRON-DEFICIENT DIENES The development of an enantioselective copper-catalysed 1,6-boration of electrondeficient dienes using B2(pin)2 has been achieved. The reactions provide chiral allylboronic esters that, after oxidation, result in secondary allylic alcohols in moderate to high yields with excellent enantioselectivities and 1,6:1,4-regioselectivities. The 1,6-borations proceed efficiently employing catalyst loadings as low as 0.0049 mol% and their scalability has been demonstrated up to 40.4 mmol. The methodology was applied to a concise synthesis of atorvastatin, in which the key 1,6-boration was performed using a catalyst loading of 0.02 mol%.
100

Preparation of chiral diimino- and diaminodiphosphine ligands and their reactivities towards transition metals

Chik, Tat Wai 01 January 1996 (has links)
No description available.

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