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Includes bibliography. / 111 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1968

Thesis (Ph.D.) -- University of Adelaide, Dept. of Physical and Inorganic Chemistry, 1968.s. / Includes bibliography.

Thesis (Ph.D.)--Washington State University. / Includes bibliographical references.

Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains viii, 76 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 54-57).

The current upgrading catalysts are mainly based on the use of expensive noble metals, which are subject to deactivation due to sintering and coking. An alternative would be to introduce a non-noble metal-based catalyst. In this work, supported molybdenum carbide based systems have been assessed for this purpose. These catalysts were formed by impregnation of zirconia (and zirconium hydroxide) and sulfated zirconia (and zirconium hydroxide) with different loadings of MoO3, with an aim of finding a balance between acid sites and metal-like sites (a site capable of performing dehydrogenation and hydrogenation function without necessarily being a metal). The synthesised catalysts were carburised between 823 and 1123 K using a mixture of methane and hydrogen (4:1) in an attempt to obtain β-Mo2C/ZrO2 or β-Mo2C/S ZrO2. Carburisation at 923 K and above resulted in molybdenum carbide with minimal or no oxygen contents. The conversion and specific rate increased with temperature. Conversion was inversely proportional to space velocity. Analysis of the products distribution as a function of conversion implies that the reaction did not simply follow a consecutive reaction pathway, but that other parallel routes were involved. Conversion increased the research octane number (RON) to ca. 66 due to the increased fraction of pentane isomers. Catalyst carburised at 823 K was approximately four times more active compared to those carburised at 923 K and above, but were of similar activity with Pt/sulfated zirconia. The non-noble metal based catalysts were stable at the reaction temperature while the Pt/sulfated zirconia catalyst deactivates.

This thesis describes the synthetic, structural and reactivity studies of η- cycloheptatrienyl-molybdenum and -tungsten chemistry. Chapter 1 presents an overview of the chemistry of η-cycloheptatrienyl derivatives of transition metals, in particular group 6 metals. The functional group properties of the η-cycloheptatrienyl ligand are also discussed. Chapter 2 describes the synthesis of [Mo(η-C₇H₇)(η⁵-C₇H₉)] from Mocl₅ or [MoCl₄(thf)₂], which provides a convenient route to η-cycloheptatrienyl-molybdenum compounds, such as [Mo(η-C₇H₇)LX₂] and [Mo(η-C₇H₇)L₂X], where L = tertiary phosphines or acetonitrile and X = halogen, [NBu₄] [Mo(η-C₇H₇)I₃], [Mo(η-C₇H₇)(η- C₅H₄R)] (R = H or Me) and [Mo(η-C₇H₇)(η⁵-C₉H₇)]. The X-ray crystal structures of [Mo(η-C₇H₇)(MeCN)I₂], [NBu₄][Mo(η-C₇H₇))I₃] and [Mo(η-C₇H₇)(η-C₅H₄Me)] are presented. The compound [Mo(η-C₇H₇))(MeCN)I₂], mixed with Me₃SiCH₂MgCl, is a catalyst for ring-opening polymerisation of norbornene giving trans polymer exclusively. The electron-transfer complexes [Mo(η-C₇H₇)(η-C₅H₄Me)][tcne] and {[Mo(η-C₇H₇))(η- C₅H₅}₂[tcnq]} and the intercalation compound {ZrS₂[Mo(η-C₇H₇)(η-C₅H₄Me)]o.22} are also described. An extension of these synthetic pathways to tungsten is described in chapter 3. Reduction of WCl₆ with sodium amalgam in the presence of cycloheptatriene gives [W(η- C₇H₇)(η⁵-C₇H₉)], which is a precursor to the compounds [W(η-C₇H₇)(MeCN)I₂], [W(η- C₇H₇)(PMe₃)X₂] (X = Br or I), [W(η-C₇H₇)(dmpe)I], [W(η-C₇H₇)(η-C₅H₄R)] (R = H or Me) and [Mo(η-C₇H₇)(η⁵-C₉H₇)]. The [W(η-C₇H₇)(MeCN)I₂] / Me₃SiCH₂MgCI system is an active catalyst for ring opening polymerisation of norbomene. The electronic structures of [W(η-C₇H₇)(η-C₅H₄R)] (R= H or Me) are discussed on the basis of their He I and He II photoelectron spectra. The intercalation of [W(η-C₇H₇)(η-C₅H₄Me)] into ZrS<suv>2</sub> is also described. The magnetic properties of the 17-electron compounds [Mo(η-C₇H₇)(MeCN)I₂], [Mo(η-C₇H₇)(PMe₃)I₂], [W(η-C₇H₇)(MeCN)I₂], [W(η-C₇H₇)(PMe₃)I₂] and [W(η-C₇H₇) (PMe₃)I₂] are discussed in chapter 4. They behave as one-dimensional antiferromagnets which was suggested by magnetic model fittings and the crystal structure of [Mo(η-C₇H₇)(MeCN)I₂]. Chapter 5 comprises of two parts. The first part describes a new series of binuclear thiolato-bridged molybdenum complexes [(η-C₇H₃R¹₄)Mo(μ-SR²)₃ Mo- (η-C₇H₃R¹₄)][BF₄] (R¹ = H or Me; R² = Et, Pr, Bu, Ph or CH₂Ph). Dynamic NMR studies reveal that all of these complexes (except for R² = Ph) are fluxional due to inversion at the pyramidal sulfur centre. Cyclic voltammetric studies show that they undergo two reversible one-electron reductions. Second part of this chapter describes the new bridging-imido compound [(η-C₇H₇)Mo(μ-NAr)₂Mo(η-C₇H₇)] (Ar = 2,6- diisopropylphenyl). Chapter 6 discusses the η-l,2,4,6-tetramethylcycloheptatrienyl-molybdenum system. The new η-tetramethylcycloheptatriene molybdenum compounds [M'(η-C₇H₄Me₄- 1,3,5,7)],[M'(η-C₇H₄Me₄-l,2,4,6)] and [M'(η-C₇H₄Me₄-l,3,4,6)], M' = Mo(CO)₃, and new η-tetramethylcycloheptatrienyl-molybdenum compounds [M"(CO)₃]+, [M"(CO)₂C1], [M"(dmpe)Cl], [M"(η-C₆H₅Me)]+ and [M"(acac)(PPh₃)], M" = Mo(η- CC₇H₃Me₄-1,2,4,6), and [Mo(η³-C₇H₃Me₄-l,2,4,6)(dmpe)(CO)₂Cl] are described. Chapter 7 gives the experimental details for the work described in preceeding chapters. Appendix A presents characterising data for all the new compounds and previously unreported data for known compounds. Crystallographic details for the X-ray structure determinations and X-ray powder diffraction data are listed in Appendix B and C respectively.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1928. / Typescript. Includes bibliographical references.

Thesis (M.S.)--Ball State University, 2009. / Title from PDF t.p. (viewed on June 07, 2010). Includes bibliographical references (p. [65]).

Access to abstract permanently restricted to Ball State community only / Construction of experimental setup -- Synthesis of MoS₂ and WS₂ fullerene like structures -- Synthesis of MoS₂ and WS₂ nanotube like structures -- Infrared spectroscopy of acetonitrile adsorption on synthesized MoS₂ materials. / Access to thesis permanently restricted to Ball State community only / Department of Chemistry