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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.
11

Advances in ansa-chromocene and gallocene chemistry /

Perrotin, Philippe. January 1900 (has links)
Thesis (Ph. D., Chemistry)--University of Idaho, August 2007. / Major professor: Pamela J. Shapiro. Includes bibliographical references. Also available online (PDF file) by subscription or by purchasing the individual file.
12

Cobalt-mediated pentadienyl/alkyne [5+2] cycloaddition reactions

Ylijoki, Kai Erik Oskar. January 2010 (has links)
Thesis (Ph. D.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on June 25, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Chemistry, University of Alberta. Includes bibliographical references.
13

Studies of the chemistry of Tröger's base, cyclopentadienones, and 2,1-benzothiazines

Rayanil, Kanok-on, January 2006 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed Aug. 10, 2007). Vita. Includes bibliographical references.
14

Synthesis and Characterization of Cyclopentadienyl Transition Metal Complexes Bearing Tetrafluoropyridyl Substituents

Warren, Andrea D. 21 August 2001 (has links)
Three new tetrafluoropyridyl-substituted cyclopentadienes were synthesized. Reactions of pentafluoropyridine (C5F5N) with sodium cyclopentadienide (NaCp) in THF with excess NaH present afforded mixtures of (4-tetrafluoropyridyl)cyclopentadiene (1), 1,3-bis(tetrafluoropyridylcyclopentadiene) (2), and 1,2-bis(tetrafluoropyridylcyclo-pentadiene) (3). Selectivity for mono- and diarylation was controlled by varying the reaction time. Each of the three cyclopentadienes (1, 2, and 3) was converted to its corresponding substituted sodium cyclopentadienide (4, 5, and 6, respectively) by treatment with NaH in THF. Reaction of the monoarylated sodium cyclopentadienide (4) with M(CO)5Br in THF (M = Mn, Re) afforded the corresponding substituted CpM(CO)3 complexes (7Mn and 7Re). The diarylated sodium cyclopentadienides (5 and 6) likewise afforded the diarylated complexes 8Mn, 8Re, 9Mn, and 9Re. Infrared spectroscopic measurements of [(C5F4N)nC5H5-n]M(CO)3 (M = Mn, Re; n = 0 - 2) revealed an increase of about 6 cm-1 in the A-symmetric C-O stretching mode per C5F4N group, which is significantly higher than the average increase (4 cm-1) found earlier for C6F5 groups. Reaction of 2 equiv of 4 with FeBr2 in THF afforded the 1,1'-diarylated ferrocene (10). Analogous reactions starting with 5 and 6 afforded tetraarylated ferrocenes (11 and 12, respectively). Reaction of 2 equiv of 4 with ZrCl4 afforded (C5F4NCp)2ZrCl2 (13), whereas the reaction of CpZrCl3 with 1 equiv of 4 afforded (C5F4NCp)CpZrCl2 (14). Metallocene (13) was found to be moderately active for ethylene/1-hexene copolymerization (1 atm of C2H4, toluene solvent, methylalumoxane cocatalyst). / Master of Science
15

Synthesis and reactivity of titanium cyclopentadienyl imido amidinate complexes

Giudice, Aldo Edwin January 2002 (has links)
This Thesis describes the preparation and characterisation of a range of titanium imido complexes supported by a cyclopentadienyl-amidinate ligand set. Reactivity studies of these complexes towards unsaturated organic species are presented. <strong>Chapter 1</strong> reviews transition metal complexes containing imido, cyclopentadienyl, and amidinate ligands, with an emphasis on recent work. <strong>Chapter 2</strong> describes the synthesis and characterisation of titanium cyclopentadienyl imido amidinate complexes, along with precursor complexes which have not been previously reported. X-ray crystal structures of four imidotitanium species are described. <strong>Chapter 3</strong> describes the reactivity of titanium cyclopentadienyl imido amidinate complexes towards carbon dioxide. An unprecedented reaction with two molecules of carbon dioxide is reported for the arylimido complexes. X-ray crystal structures of two of the arylimido dicarboxylate products are described. The kinetics of the insertion of the second molecule of carbon dioxide are investigated and reported. <strong>Chapter 4</strong> describes the reactivity of titanium cyclopentadienyl imido amidinate complexes towards isocyanates and carbodiimides. The X-ray crystal structures of two N, O- bound ureate complexes are described. A new series of reactions involving two molecules of p-tolyl isocyanate with arylimido complexes is reported. Reactions of isocyanates with carbamate complexes are also reported. <strong>Chapter 5</strong> explores the reactivity of titanium cyclopentadienyl imido amidinate complexes towards sulfur-containing substrates. Comparisons are drawn with the reactivity towards oxygen-bearing homologues. X-ray crystal structures of two bridging sulfido complexes are described. <strong>Chapter 6</strong> discusses the reactivity of titanium cyclopentadienyl imido amidinate complexes towards substrates containing only one unsaturated linkage. Reactions with organic carbonyls and terminal alkynes are found to afford equilibria rather than isolable products. <strong>Chapter 7</strong> details full experimental procedures for all syntheses and reactions described in the text. <strong>Chapter 8</strong> contains characterising data for all new compounds reported. Full tables of crystallographic data for all new crystallographically characterised complexes described herein are presented in <strong>Appendices A-H, J-M</strong>. <strong>Appendix I</strong> contains kinetics data relating to work discussed in Chapter 3.
16

Solventless substitution chemistry of iron and ruthenium metal carbonyl complexes

Munyaneza, Apollinaire 06 March 2008 (has links)
ABSTRACT Solventless reactions of substituted cyclopentadienyl metal carbonyls of iron and ruthenium with electron donor ligands have been carried out. The reactions between CpFe(CO)2I and a range of phosphine ligands occurred in melt phase and yielded two typical compounds : salt product, [CpFe(CO)2PR3]I, and non-salt product, CpFe(CO)PR3I with the salt product being predominant. The complex [CpFe(CO)2]2 was used to catalyze these reactions. The progress of the reactions was followed by 1H NMR spectroscopy. The characterization of products correlates well with the products obtained when working in solution medium. The presence of a Me substituent on the Cp ring was found to favour the salt product formation but generally led to lower rates of reaction. Solventless reactions between RCpRu(CO)2I (R = H, Me) and solid phosphine ligands were also carried out. It has been observed that the ruthenium complexes were less reactive compared with their iron analogues but led to the same types of products namely salt and non-salt. The phosphite ligands were found to be less reactive than their phosphine analogues. In fact, the solventless reactions between RCpM(CO)2I (R = H, Me; M = Fe, Ru) were very slow even in the presence of [CpFe(CO)2]2 as a catalyst. However, when Me3NO.2H2O was added to the reaction mixture in solventless conditions, the non-salt product was obtained in a short period of time at 80oC. A range of cyclopentadienyl based metal complexes e.g [CpMo(CO)3]2, [MeCpRu(CO)2]2 etc. and palladium based compounds such as PdO, Pd/CaCO3 5% etc. were found to be good catalysts for the solventless reactions between CpFe(CO)2I and PPh3. Solventless migratory-insertion reactions have been successfully conducted between CpFe(CO)2CH3 and a range of solid phosphine ligands. Only the acetyl products, CpFe(CO)[PR3]COCH3 were obtained. SO2 insertion into RCpFe(CO)2R’ (R = H, CH3; R’ = CH3, CH2Ph) occurred quite easily at room temperature. However, when R was a carboxylic acid group, CO2H, no reaction took place. CO insertion into the same systems did not happen in solventless conditions.
17

Synthetic inorganic chemistry : novel metallocenes and inorganic fullerenes

Clancy, Gerald Patrick January 2000 (has links)
This thesis is divided into two parts. The first part concerns the synthesis and characterisation of substituted metallocene complexes of the transition and main group metals. The second part describes the preparation and characterisation of inorganic fullerene (IF)-related materials. <strong>Chapter 1</strong> reviews the chemistry of dialkyl- and diaryl-phosphino substituted cyclopentadienyl complexes of the transition metals. <strong>Chapter 2</strong> describes the synthesis and characterisation of the new ligands [M(C<sub>5</sub>Me<sub>4</sub>)CH<sub>2</sub>PMe<sub>2</sub>] (M = H, Li, Na and K) via the precursors [HC<sub>5</sub>Me<sub>4</sub>)CH<sub>2</sub>PHMe<sub>2</sub>][X] (X = Cl and PF<sub>6</sub>). The synthesis, characterisation and chemical reactivity of the compounds [Zr{{η-C<sub>5</sub>Me<sub>4</sub>)CH<sub>2</sub>PMe<sub>2</sub>}<sub>2</sub>Cl<sub>2</sub> and [Mn{η-C<sub>5</sub>Me<sub>4</sub>)CH<sub>2</sub>PMe<sub>2</sub>}<sub>2</sub>] is reported together with supporting evidence for the synthesis of the bimetallic complex [Zr{U+03B7-C<sub>5</sub>Me<sub>4</sub>)CH<sub>2</sub>PMe<sub>2</sub>}<sub>2</sub>Cl<sub>2</sub>PtI<sub>2</sub>] and the complex [Mn{η-C<sub>5</sub>Me<sub>4</sub>)CH<sub>2</sub>PMe<sub>2</sub>B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>}<sub>2</sub>]. <strong>Chapter 3</strong> provides a brief introduction into the field of main group metallocenes and describes the synthesis and characterisation of the new main group metallocenes [M{η- C<sub>5</sub>H<sub>4</sub>)CMe<sub>2</sub>PMe<sub>2</sub>}<sub>2</sub>] (M = Pb and Sn). The B(C<sub>6</sub>F<sub>5</sub>)<sub>3 adduct [Pb{η-C<sub>5</sub>H<sub>4</sub>)CMe<sub>2</sub>PMe<sub>2</sub>(B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>}<sub>2</sub>] has also been synthesised. The main group - transition metal bimetallic complex [Pb{η-C<sub>5</sub>H<sub>4</sub>)CMe<sub>2</sub>PMe<sub>2</sub>}<sub>2</sub>PtI<sub>2<sub> in which the substitutedplumbocene acts as a bidentate ligand, has been characterised by mass spectrometry and <sup>31</sup>P{<sup>1</sup>H}NMR spectroscopy. <strong>Chapter 4</strong> provides an introduction into the field of IF-related materials and an overview of the analytical techniques used in their characterisation. <strong>Chapter 5</strong> describes the preparation and characterisation of IF-MoS<sub>2</sub> and IF-(Nb,W)S<sub>2</sub> materials from MoC and the binary oxides Nb<sub>8</sub> W<sub>9</sub>O<sub>47</sub> and Nb<sub>4</sub>W<sub>13</sub>O<sub>47</sub> respectively. A powder X-ray diffraction study of the conversion of WC to WO<sub>3-X</sub> and the subsequent sulfidisation by H<sub>2</sub>S to form novel IF-WS<sub>2</sub> morphologies is also described. <strong>Chapter 6</strong> describes the preparation of amorphous Group 5 metal (V, Nb and Ta) oxides using the metal vapour synthesis technique. These amorphous precursors have been annealed in a reducing atmosphere to form the oxide phases U+03B1-V<sub>2</sub>O<sub>3</sub>, NbO<sub>2</sub> and TT-Ta<sub>2</sub>O<sub>5</sub> which have been identified by powder X-ray diffraction. Upon reaction with H<sub>2</sub>S, the crystalline oxides afford layered sulfides of the form MS<sub>2</sub> (M = V, Nb and Ta), some of which exhibit behaviour typical of IF-like materials and have been characterised by HRTEM, powder X-ray diffraction and EDX analysis. Chapter 7 outlines the experimental details for the synthesis, characterisation, reactions and compounds described in the preceding chapters. <strong>Chapter 8</strong> presents the characterising data for the new compounds described in chapters 2 and 3. <strong>Appendix A</strong> contains details of the crystallographic data for the structurally characterised compound [Mn{η-C<sub>5</sub>Me<sub>4</sub>)CH<sub>PMe<sub>2</sub>}<sub>2</sub>].
18

Toward curved polycyclic aromatic hydrocarbons (PAHs)

Wanene, Wilson Kamau. January 2007 (has links)
Thesis (M.S.)--University of Nevada, Reno, 2007. / Includes bibliographical references. Online version available on the World Wide Web.
19

Diels-alder reactions of a cyclopentadienone derivative

Gomes, Maria Goretti, January 2007 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on February 13, 2008) Vita. Includes bibliographical references.
20

Thermal rearrangements of 3H-pyrazoles, 4H-pyrazoles, and cyclopentadienes.

Jefferson, Elizabeth Anne. Warkentin, John. Unknown Date (has links)
Thesis (Ph.D.)--McMaster University (Canada), 1992. / Source: Dissertation Abstracts International, Volume: 54-08, Section: B, page: 4161. Adviser: John Warkentin.

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