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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.
1

Synthesis and study of ferrocene derivatives

Overton, Donald Eugene, January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Synthesis, characterization and reactions of novel ferrocenylimidazoles as donor ligands

Onyancha, Douglas Okerio January 2010 (has links)
In this project a series of ferrocenylimidazole derivatives were successfully prepared and characterized using an array of analytical techniques. Reactions of ferrocenylcarbinols with N,N′-thiocarbonyldiimidazole under both solvent-free conditions and in dichloromethane are described. The reaction of ferrocenylmethanol afforded S,S-bis(ferrocenylmethyl)dithiocarbonate, the reaction of α-substituted ferrocenylcarbinols provided ferrocenylalkylimidazolides, while ω-ferrocenylcarbinols yielded ferrocenylimidazolecarbothioates. The reactions were carried out under solvent-free conditions, consistent with the principles of Green Chemistry. Ferrocenyl benzyl ethers were successfully prepared by reacting 4-ferrocenylbenzyl-1Hcarboxylate with a series of primary alcohols under catalytic condition and under a catalyst– free environment. Refluxing a mixture of alcohol-water and 4-ferrocenylbenzyl-1Hcarboxylate provided the corresponding ethers in modest yields. The same ethers were obtained at room temperature by employing potassium tetrachloroplatinate or hydrochloric acid as catalyst. Ferrocenyl-1H-imidazole, 4-ferrocenylphenyl-1H-imidazole and their corresponding ferrocenyl-3-subsitituted imidazolium salts have been successfully synthesized. The compounds were characterized and the electrochemical properties of selected imidazolium salts were examined by cyclic voltammetry. Additionally, X-ray structures of two of the imidazolium salts were determined. The imidazolium salts were found to be good catalysts for the Heck and Suzuki cross-coupling reactions.
3

The crystal structures of biferrocenyl

Macdonald, Alaistair Cumming January 1964 (has links)
Biferrocenyi, C₅H₅,Fe,C₅H₄. C₅H₄ .Fe.C₅H₅., crystallises in the monoclinic system with a = 10.35, b = 7.87, c = 12,63Å and β = 131.72˚. The space group is P2₁/c and there are two molecules per unit cell, thus a molecular centre of symmetry is required which occurs at the mid-point of the carbon-carbon bond joining the ferrocene derivatives hence the molecular configuration is trans. The intensities of 1,111 reflections were measured by means of a scintillation counter using Mo K∝ radiation. The structure determination was based on heavy atom Patterson and Fourier methods and refined by least squares and differential syntheses. The final discrepancy, R, for the 896 observed reflections is 0.16. Each iron atom is sandwiched between two five-membered rings which are planar, almost parallel and 3.32Å apart. Their relative conformations are approximately midway between the staggered and the eclipsed. The two bonded rings are coplanar, the bond between the two being 1.48Å long. The mean bond lengths are Fe - C = 2.04 Åand C – C in the rings 1.40Å However there are deviations from five-fold symmetry in the rings which may be significant, furthermore these deviations are the same in both crystallographically independent rings, are similar to those found in ferrocene and may be related to the iron-carbon bonding pattern. All intermolecular contacts correspond to normal van der Waals interactions. / Science, Faculty of / Chemistry, Department of / Graduate
4

Novel tripodal ligands designed to complex anions

Hopkins, Peter K. January 1999 (has links)
No description available.
5

Ferrocenyl ligands for atom transfer radical polymerization

Chiang, Pui-Ren 07 August 2007 (has links)
One of the most effective methods for precision polymer synthesis is controlled radical polymerization, in which atom transfer radical polymerization (ATRP) is an excellent example. A series of ferrocene derivatives were prepared and applied for polymerization of methyl methacrylate (MMA). Formulation by combination of the ferrocenyl ligands and coprous bromide could catalyze ATRP, of which the performance is strongly dependent on the substituents on the Cp rings as well as the reaction condition. The redox potentials of the ferrocene derivatives reveal that the lower E1/2, the better performance on ATRP. The results also showed that the molecular structures of the catalysts determined by X-ray crystallography also play an important role for the performance of the polymerization.
6

Ferrocenes of Substituted Indenyl Ligands

Fern, Glen Matthew January 2005 (has links)
This thesis describes the preparation and characterization of a variety of methyl-, trimethylsilyl-, and diphenylphosphino-substituted indenes. The indenes were then used in the preparation of bis(indenyl)iron(II) complexes. The bis(indenyl)iron(II) complexes were characterized by ¹H, ¹³C, and ³¹P-NMR, UV/visible spectroscopy, cyclic voltammetry, and mass spectrometry. The cyclic voltammetry shows an approximately linear relationship between the oxidation potential and the type of substituent and its ring position, but with increasing substitution leads to lower than expected oxidation potentials. The UV/visible spectra show two absorption bands in the visible region. The position of the bands are essentially unaffected by methyl-substitution, but the low energy band red-shifts with trimethylsilyl- and diphenylphosphino-substitution. Di(2-methylindenyl)iron(II), bis(4,7-dimethyl-indenyl)iron(II), bis(1,3-bis(trimethylsilyl)indenyl)iron(II), rac-bis(1-diphenyl-phosphinoindenyl)iron(II), rac-bis(1-diphenylphosphino-3-methylindenyl)iron(II), and rac-bis(1-diphenylphosphino-2,3-dimethylindenyl)iron(II) were characterized by X-ray crystallography.The planar chiral ferrocenylphosphine bis(1-diphenylphosphinoindenyl)iron(II) is observed to undergo a facile ring-flipping isomerization from the meso isomer to the racemic isomer in THF at ambient temperature. The isomerization is slowed by the addition of the noncoordinating solvent chloroform, but is accelerated by the addition of LiCl. Rate and activation parameters for the isomerization have been determined to be: kobs = 1.6 x 10⁻⁵ s⁻¹ at 23 ℃, ΔH‡ = 58 ± 4 kJ mol⁻¹, ΔS‡ = −140 ± 15 J mol⁻¹ K⁻¹. Deuterium labeling of bis(1-diphenylphosphinoindenyl)iron(II) in the 3- and 3ʹ-position ruled out the isomerization proceeding by [1,5]-proton shifts or dissociative mechanisms. The proposed mechanism for the isomerization proceeds via coordination of two THF ligands with ring-slippage of one of the indenyl ligands until it is coordinated through the phosphine. Coordination of the indenyl ligand by the other face leads to the formation of the other isomer.The heterobimetallic complexes (bis(1-diphenylphosphinoindenyl)iron(II))-cis-dichloropalladium(II), (bis(1-diphenylphosphinoindenyl)iron(II))-cis-dichloro-platinum(II), and [(cyclooctadiene)(rac-bis(1-diphenylphosphinoindenyl)iron(II))-rhodium(I)] tetraphenylborate were prepared. Attempts to prepare dichloro(bis(1-diphenylphosphinoindenyl)iron(II))nickel(II) lead to the formation of trans-dichloro(bis(1-diphenylphosphinoindene))nickel(II). The complex (bis(1-diphenyl-phosphinoindenyl)iron(II))-cis-dichloropalladium(II) is able to catalyze the cross-coupling of bromobenzene with n-/sec-butylmagnesium chloride. However. the reaction is not selective with isomerization of the alkyl group and reduction of the halide occurring via a β-hydride elimination mechanism.
7

Synthesis and properties of some novel liquid crystalline systems including metallomesogens

Scribbins, Ashley Chandler January 1997 (has links)
No description available.
8

Ferrocene conjugates as potential anticancer agents

Dago N’Da, David 10 February 2006 (has links)
PhD - Science / Methotrexate (MTX) is a highly potent drug against leukemia and other neoplasias. The drug is notorious, however, for exerting toxic side effects and inducing drug resistance in the target cells as a result of deficiencies in the active carrier-mediated membrane-crossing mechanism. The bioreversible binding to a water-soluble and biocompatible carrier polymer is an advanced technology designed to circumvent critical pharmacological hurdles the drug must clear for efficacious biological action. The present project aimed at the anchoring of MTX and other drugs to various primary amine-functionalized polymeric carriers and the evaluation of the cytotoxic performance of the resulting conjugates in cell culture tests. The polymeric carriers used were polyaspartamides, prepared by an aminolytic ring-opening process of polysuccinimide, and poly(amidoamines), on the other hand, obtained by the copolymerization of methylenebisacrylamide with mono-N- tert-butoxycarbonyl-protected primary diamine and bifunctional amines. The anchoring was achieved through formation of biofissionable amide bonds. The in vitro biological evaluation against various human cell lines revealed the polymer-MTX conjugates to be more active than the clinically used parent drug. In order to demonstrate the multidrug-binding capacity of the polyaspartamidetype carriers, and at the same time ensuring target-specific drug delivery, folic acid, a potential cell entry facilitator, was co-conjugated to selected polymeric conjugates containing MTX or ferrocene. The in vitro inhibition of cell growth by the folate-drug co-conjugates was also evaluated against the same human cell lines.
9

Synthesis and electrochemistry of tetrapyrrole derivatives substituted with ferrocenyl moieties.

January 1999 (has links)
by Ka-Wo Poon. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (leaves 113-120). / Abstracts in English and Chinese. / ABSTRACT --- p.i / ACKNOWLEDGMENT --- p.iii / CONTENTS --- p.iv / LIST OF FIGURES --- p.vi / LIST OF TABLES --- p.x / ABBREVIATIONS --- p.xi / Chapter 1. --- INTRODUCTION --- p.1 / Chapter 1.1 --- General Background of Tetrapyrrole Derivatives --- p.1 / Chapter 1.2 --- Electronic Interactions in Systems with Multiple Redox Sites --- p.8 / Chapter 1.2.1 --- Electronic Interactions in One-dimensional Systems --- p.9 / Chapter 1.2.2 --- Electronic Interactions in Three-dimensional Systems --- p.12 / Chapter 1.3 --- Ferrocene-containing Tetrapyrrole Derivatives --- p.22 / Chapter 1.3.1 --- Ferrocene-containing Porphyrins --- p.22 / Chapter 1.3.2 --- Ferrocene-containing Porphyrazines --- p.29 / Chapter 1.3.3 --- Ferrocene-containing Phthalocyanines --- p.30 / Chapter 2. --- RESULTS AND DISCUSSION --- p.38 / Chapter 2.1 --- Ferrocenylphthalocyanines with Oxyethylene Linkers --- p.38 / Chapter 2.1.1 --- Synthesis and Characterization --- p.38 / Chapter 2.1.1.1 --- Preparation of Tetrakis(2-ferrocenylethoxy)- phthalocyaninatozinc(II) (55) --- p.38 / Chapter 2.1.1.2 --- Preparation of Octakis(2-ferrocenylethoxy)- phthalocyaninatozinc(II) (62) --- p.43 / Chapter 2.1.1.3 --- Preparation of Metal Free Hexadecakis(2- ferrocenylethoxy)phthalocyanine (65) --- p.49 / Chapter 2.1.2 --- Electronic Absorption Spectra --- p.52 / Chapter 2.1.3 --- Electrochemical Studies --- p.60 / Chapter 2.2 --- Ferrocenyl Tetrapyrroles with Ethynyl Linkers --- p.68 / Chapter 2.2.1 --- Synthesis and Characterization --- p.68 / Chapter 2.2.1.1 --- Preparation of Octakis(ferrocenylethynyl)- phthalocyaninatozinc(II) (83) --- p.71 / Chapter 2.2.1.2 --- Preparation of Octakis(ferrocenylethynyl)- Naphthalocyaninatozinc(II) (87) --- p.76 / Chapter 2.2.1.3 --- "Preparation of 5,15-bis(ferrocenylethynyl)- 10,20-diphenylporphyrinatonickel(II) (90)" --- p.81 / Chapter 2.2.2 --- Electrochemical Studies --- p.84 / Chapter 2.3 --- Conclusion --- p.92 / Chapter 3. --- EXPERIMENTAL SECTION --- p.93 / Chapter 3.1 --- General Methods --- p.93 / Chapter 3.2 --- Physical Measurements --- p.93 / Chapter 3.3 --- Synthesis of Ferrocenylphthalocyanines with Oxyethylene Linkers --- p.95 / Chapter 3.4 --- Synthesis of Ferrocenyl Tetrapyrrole Derivatives with Ethynyl Linkers --- p.105 / Chapter 4. --- REFERENCES --- p.111 / Chapter APPENDIX A --- 1H NMR spectra of dinitriles --- p.121 / Chapter APPENDIX B --- 13C̐ưث1H }NMR spectra of dinitriles --- p.126
10

Synthesis, structural characterization and reactivity of planar chiral derivatives of Ferrocene. / CUHK electronic theses & dissertations collection

January 1999 (has links)
Gang Zhao. / "June 1999." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (p. 147-153). / 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.

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