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Design, synthesis, and characterization of [1--]3 ; 1--](2 + 1 Me) ; 1--](2 + 1)] C-branched dendrons and dendritic architecturesKotta, Kishore Kumar. January 2006 (has links)
Thesis (Ph. D.)--University of Akron, Dept. of Chemistry, 2006. / "May, 2006." Title from electronic dissertation title page (viewed 09/17/2006). Advisor, George R. Newkome; Committee members, Michael J. Taschner, David A. Modarelli, Chrys Wesdemiotis, Robert R. Mallik; Department Chair, Michael J. Taschner; Dean of the College, Ronald F. Levant; Dean of the Graduate School, George R. Newkome. Includes bibliographical references.
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Synthesis of a new series of polyhydrocarbon-based dendritic fragments.January 1999 (has links)
by Ka-Fai Ng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 51-54). / Abstracts in English and Chinese. / Contents --- p.i / Acknowledgments --- p.iii / Abstract --- p.iv / Abbreviations --- p.vi / Chapter Chapter I --- Introduction / Chapter I-1 --- General background of dendrimers --- p.1 / Chapter I-2 --- Synthesis of dendritic molecules --- p.2 / Chapter I-2-1 --- Divergent methods --- p.2 / Chapter I-2-2 --- Convergent methods --- p.4 / Chapter Chapter II --- Functional dendrimers / Chapter II-1 --- Catalytically active dendrimers --- p.8 / Chapter II-2 --- Polyhydrocarbon-based dendrimers --- p.17 / Chapter Chapter III --- Results and Discussion / Chapter III-1 --- Solvent dependence of the rate of Diels-Alder reaction --- p.23 / Chapter III-2 --- Synthesis and characterization of polyhydrocarbon-based dendritic fragments --- p.25 / Chapter III-2-1 --- Architecture of the dendritic fragments --- p.25 / Chapter III-2-2 --- The iterative cycle --- p.27 / Chapter III-2-3 --- Synthesis of GO dendrimer --- p.28 / Chapter III-2-4 --- Construction of G1 dendrimers --- p.29 / Chapter III-2-5 --- Construction of the G2 dendrimers --- p.31 / Chapter III-3 --- Conclusions --- p.36 / Chapter Chapter IV --- Summary --- p.37 / Chapter Chapter V --- Experimental --- p.38 / References --- p.51 / Spectra --- p.55
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Synthesis of metallodendrimers.January 2000 (has links)
by Pui-Shan Fung. / Thesis submitted in: December 1999. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 67-69). / Abstracts in English and Chinese. / Acknowledgments --- p.ii / Abstract --- p.iii / Abbreviations --- p.v / Chapter Chapter I. --- Introduction / Chapter 1. --- General background of dendrimers --- p.1 / Chapter 2. --- Metallodendrimers --- p.4 / Chapter 3. --- Fluorinated dendrimers --- p.12 / Chapter Chapter II. --- Synthesis and characterization / Chapter 1. --- Structure of the dendritic fragments --- p.15 / Chapter 2. --- Synthesis of the terpy-based metallodendrimers --- p.16 / Chapter 3. --- Characterization / Chapter 3.1 --- Characterization of fluorinated dendrimers --- p.31 / Chapter 3.2 --- Characterization of non-fluorinated dendrimers --- p.36 / Chapter Chapter III. --- Redox properties of metallodendrimers / Chapter 1. --- Cyclic voltammetric studies --- p.38 / Chapter 1.1 --- Cyclic voltammograms of fluorinated metallodendrimers --- p.40 / Chapter 1.2 --- Cyclic voltammograms of non-fluorinated metallodendrimers --- p.44 / Chapter Chapter IV. --- Summary --- p.47 / Chapter Chapter V. --- Experimental --- p.49 / References --- p.67 / Spectra --- p.70
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An accelerated approach to the synthesis of dendrimers.January 1999 (has links)
by Vincent Yam-Fat Lau. / Thesis submitted in: November 1998. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 53-57). / Abstract also in Chinese. / Contents --- p.i / Acknowledgments --- p.ii / Publication --- p.iii / Abstract --- p.iv / Abbreviations --- p.vi / Chapter Chapter I. --- Introduction / Chapter 1. --- General background of synthetic chemistry in dendrimers --- p.1 / Chapter 2. --- Accelerated approaches --- p.5 / Chapter Chapter II. --- Synthesis and Characterization / Chapter 1. --- Structure of the dendritic fragments --- p.17 / Chapter 2. --- Synthesis of the dendritic fragments --- p.18 / Chapter 3. --- Characterization --- p.26 / Chapter Chapter III. --- Attempted Synthesis of Electrochemically Active Metallodendrimers / Chapter 1. --- Background --- p.30 / Chapter 2. --- Synthesis of a ferrocene containing spacer for the construction of metallodendrimers containing multiple redox active units --- p.35 / Chapter 3. --- Conclusions --- p.41 / Chapter Chapter IV. --- Summary --- p.42 / Chapter Chapter V. --- Experimental --- p.43 / References --- p.53 / Spectra --- p.58
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Synthesis feasibility and efficiency of post-modification of multifunctional dendrimers. / CUHK electronic theses & dissertations collectionJanuary 2010 (has links)
The synthetic efficacy of the dendrimer backbone rearrangement was examined by conducting heterogeneous Ramburg-Backlund rearrangements (alumina supported KOH, CBr2F2/THF/t-BuOH = 1/1/1) on dibenzylsulfone G3-CCSO2-dendrimer 141 and G3-CSO2C-dendrimer 142. Again, steric inhibition was found to play a prominent role in dictating the chemical reactivity of the sulfone moieties under heterogeneous conditions. The innermost sulfones in compound 141 were found to be relatively inert and at most only 1 out of the 3 sulfones could undergo the rearrangement, and the major product was the starting material. On the other hand, up to 3 or 4 of the intermediate layer sulfone moieties underwent the rearrangement reaction to give the triene-tris(sulfone) 145 or tetraene-bis(sulfone) 144 products. For the first time in the literature, conclusive mass spectral evidence was obtained to unveil the detailed outcome of such complex dendrimer backbone rearrangement reactions. / The synthetic efficiency of the dendrimer interior functional group conversion method was exemplified by converting the dibenzyl sulfide moieties in G3-CCS-dendrimer 68 and G3-CSC-dendrimer 69 to the corresponding dibenzyl sulfone under either heterogeneous (oxone in CH2Cl2) or homogeneous (35% H2O2 in CH2Cl2/HOAc) conditions. The effect of steric inhibition was prominent under the heterogeneous conditions as the solid oxone particles failed to penetrate into the dendrimer interior to initiate the oxidation reaction. On the other hand, dendrimers 68, 69 and 136 could be oxidized to the corresponding dibenzyl sulfones via the dibenzyl sulfoxides under homogeneous conditions. For the first oxidation to the dibenzyl sulfoxides, both compounds 68 and 69 proceeded with similar speed, indicating the similar steric environment between the innermost and intermediate layers of dibenzylsulfide moieties. On the other hand, the innermost dibenzyl sulfoxides in compound 68, in comparison to the dibenzyl sulfoxides in the middle layer in compound 69, underwent further oxidation to the dibenzyl sulfones with greater ease. This finding suggested that there were other factors, in addition to steric inhibition, in controlling the chemical reactivity of functional groups inside the dendrimer matrix. Our speculation was that the microenvironment polarity of the dendrimer interior could also play an important role in facilitating/retarding the diffusion of external chemical reagents into the interior of the dendrimer. / Two layer-block G3-CCS-dendrimer 68 and G3-CSC-dendrimer 69 with dibenzylsulfide functionalities embedded in the innermost and intermediate dendritic layers, respectively, were synthesized by a convergent method. The key steps involved in their constructions were Horner-Wadsworth-Emmons olefination and thiol-mediated alkylation reaction. A third target G3-SCC-dendrimer 70, with dibenzylsulfide moieties located in the outermost dendritic layer, could not be synthesized despite many attempts. A fourth model G3-SSS-dendrimer 136 containing 21 dibenzyl sulfone moieties in the innermost, middle and outermost layers was also prepared. All synthesized compounds were characterized by 1H and 13C nuclear magnetic resonance spectroscopy, mass spectrometry, elemental analysis and/or size exclusion chromatography. They were prepared in order to probe the feasibility of and the effect of dendritic shielding on two novel dendrimer synthesis methodologies, namely, dendrimer interior functional group conversion and dendrimer backbone rearrangement. / Cheng, Wing Sum. / Adviser: H. F. Chow. / Source: Dissertation Abstracts International, Volume: 73-01, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 117-124). / 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, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
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Dendrimer templated silica networks synthesis, characterization and application in silver nanoparticle construction /Liu, Xiaojun, January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Chemistry. Title from title page of PDF (viewed 2008/07/30). Includes bibliographical references.
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Dumbbell shaped dendrimers synthesis, characterization and applications in assembling silver nanoparticles /Vassilieff, Tatiana S. January 1900 (has links)
Thesis (M.Sc.). / Written for the Dept. of Chemistry. Title from title page of PDF (viewed 2008/07/30). Includes bibliographical references.
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Synthesis, characterization and deposition of dendrimers using a continuous flow microreactor /Liu, Shuhong. January 2007 (has links)
Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 145-146). Also available on the World Wide Web.
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Design and synthesis of dendrimers for studying two-photon absorption characteristicsSims, Michael Keith. January 2007 (has links) (PDF)
Thesis (M.S.)--Montana State University--Bozeman, 2007. / Typescript. Chairperson, Graduate Committee: Charles W. Spangler. Includes bibliographical references (leaves 54-55).
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Synthesis and characterization of novel BINOL-based symmetrical and asymmetrical axially chiral dendrimersGobouri, Adil Abdullah H. January 2012 (has links)
Synthesis of optically active dendrimers based on 1,1'-bi-2-naphthol enantiomers and their derivatives as core units is growing rapidly due to the unique behavior and properties of the new compounds and their various valuable applications in several fields such as asymmetric catalysts, enantioselective fluorescent sensors and in chiral molecular recognition. To the best of our knowledge, the synthesis of binaphthyl-based symmetrical and asymmetrical axially chiral dendrimers via 1,3-cycloaddition reactions ["Click" chemistry] using Fréchet-type dendrons and their azido-analogues has not been studied yet. The principal aim of this project was the synthesis and characterization of a novel series of binaphthyl-based symmetrical and asymmetrical axially chiral dendrimers via "Click" and etherification reactions, and then determination of the specific and molar rotation of the new dendrimers to investigate the influence of linkage nature between the dendritic wedges and the core units on the optical properties in presence of the triazole ring by comparing of the properties of the new dendrimers with the dendrimers reported in literature, in addition to study the influences of different chemical groups near the dendritic wedges on the optical properties of the novel synthesized dendrimers. In conclusion, several families of novel BINOL-based symmetrical and asymmetrical axially chiral dendrimers have been synthesized by the reaction of well-known BINOL derivatives as core units with Fréchet-type dendrons and their azido-analogues via "Click" and etherfication reactions for the first time. All new dendrimers were obtained in very good yields which confirm the effectiveness of "Click" reaction in this type of synthesis. The new dendrimers were fully characterized by 1H, 13C and HMQC NMR spectroscopy, mass spectrometry, IR spectroscopy and UV-Vis spectrometry. All new dendrimers show moderate optical activity. Changes in the specific and molar rotation are characterized by a general decrease in the specific rotation and a general increase in the molar rotation with the increase in the dendritic wedges generation in each series of the synthesized dendrimers. By our current knowledge, the increase in the specific rotation as generation increases of (S)-358, (S)-359 and (S)-360 observed in this research is the first such observation. The presence of the triazole ring in the linkage between the core unit and the dendritic wedges plays an important role in reducing of the steric repulsion between the two naphthyl units and in reducing of the effect of the dendritic wedges generation on the torsional angle by making the wedges far away from the attachment point of the two naphthyl units.
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