Inorganic Chemistry Commons^™

Development Of Late Transition Metal Complexes To Enable Sustainable Organic Oxidations, Alexander Scott Phearman

Publicly Accessible Penn Dissertations

This thesis describes the synthesis, characterization, and reactivity of transition metal complexes, with a focus on enabling sustainable partial oxidations of organic chemicals using molecular oxygen and water as oxidants. Chapter 2 discusses the development of several new precatalysts for the Aldehyde-Water Shift reaction, the conversion of aldehydes and water to carboxylic acids and H2. These studies resulted in the most selective and active precatalyst to date for the AWS reaction. Also examined were the effects of changing pH and venting reaction headspace on both selectivity and activity. Chapter 3 outlines the synthesis of a novel pincer ligand precursor and …

The Interplay Between Anions And Radicals In Synthesis, Spectroscopy, And Catalysis, Grace Banks Panetti

Publicly Accessible Penn Dissertations

This dissertation describes studies in the fields of lanthanide-containing heterobimetallic complexes, organic super-electron donors, CeIV–C bonds, and titanium photocatalysts. In all cases, reactive species were isolated and studied via a combination of single crystal X-ray diffractometry, electrochemistry, NMR spectroscopy, and reactivity. These studies were developed to understand new fundamental bonding between new types of bonds or to understand these species role in reactivity. Either the presence of CuI cations in the secondary coordination sphere or the use of sulfur donor atoms in the primary coordination sphere resulted in unusual architectures in the Shibasaki rare earth alkali metal BINOLate (REMB) framework. …

Purification And Activity Analysis Of A Highly Active Recombinant Catalase From Psychrophilic Bacterium Psychrobacter Cryohaloentis, Andrew Stewart

Honors Program Theses

To date, the genus Psychrobacter includes 37 recognized bacterial species isolated from different sources ranging from Siberian permafrost (P. cryohalolentis) to seal feces (P. lutiphocae). Due to its diverse ecological niches, several species belonging to the genus have different enzymatic activities with potential applications in bioremediation and the food industry. In this study, a bioprospecting approach was used to perform a in depth analysis of a Psychrobacter-like bacterial strain isolated from goose feces (designated as Psychrobacter unknown). The phylogenetic analysis of 16S rRNA gene and homologous sequence studies suggest that the strain may represent a novel species of the Psychrobacter …

Characterization Of Modern Ammunition And Background Profiles: A Novel Approach And Probabilistic Interpretation Of Inorganic Gunshot Residue, Korina Layli Menking-Hoggatt

Graduate Theses, Dissertations, and Problem Reports

Gunshot residue (GSR) can provide essential clues in gun-related investigations. The standard practice for GSR analysis uses SEM-EDS, with the capability for single particle elemental and morphological analysis. However, the method is time-consuming and based on categorical classification models without considering case circumstances. Therefore, complementary and more encompassing methods are needed to improve evidence interpretation of modern ammunition. This research aims to fill these demands by developing standard materials and alternative methods to characterize and interpret IGSR.

This study developed primer GSR (pGSR) standards from sixty discharged primers that were fully characterized by three techniques. The number of GSR particles, …

Palladium-Catalyzed Deprotonative Cross-Coupling And Carbonylative Cross-Coupling Processes, Bowen Hu

Publicly Accessible Penn Dissertations

Metal-catalyzed direct C−H bond activation arylation reactions of non- or weakly acidic C−H bonds have recently received much attention. Compared to traditional catalysts that activate C−H bonds, conventional deprotonative cross-coupling processes (DCCP) undergoes an in-situ C−H deprotonation and metalation of the substrate under catalytic cross-coupling conditions. DCCP reactions are generally directing-group-free methods employing simple starting materials under mild reaction conditions. This thesis describes mechanistic study of DCCP-type triarylation of benzylic methyl groups and introduces two novel methods of deprotonative carbonylation of weakly acidic benzylic C(sp3)−H bonds.

In Chapter 1, a comprehensive mechanistic study of our palladium-catalyzed deprotonative triarylation of heteroarylmethanes …

Mechanistic Insight Into The Partial Oxidation Of Methane To Methanol Using Platinum And Palladium Complexes, Hannah Elizabeth Zeitler

Publicly Accessible Penn Dissertations

The efficient conversion of methane into methanol is a priority in energy research as it converts methane, a greenhouse gas, to methanol, a transportable liquid that is ubiquitous in chemical industry. Detailed within are efforts towards the development of palladium and platinum homogeneous catalysts that will selectively oxidize methane to methanol using dioxygen as the oxidant. There are three proposed steps for this challenging transformation: 1) selective C–H activation 2) oxidation and 3) release of product. A potential mechanism for C–H activation is metal-ligand cooperation (MLC) in which the metal and ligand are involved in cleaving C–H bonds. As the …

Investigating The Impacts Of Internal Electrostatic Fields On Homogeneous Transition Metal Complexes, Alexander Bent Weberg

Publicly Accessible Penn Dissertations

The use of electrostatic fields to influence chemical reactivity is a rapidly growing field ofstudy and is increasingly invoked as a strong contributor to enzyme catalysis. Analogous research applied to homogeneous inorganic chemistry remains comparatively underexplored, however several recent examples of transition metal complexes containing rigidly oriented internal electrostatic fields have showcased promising advantages associated with this “non-classical” design strategy. Herein, we report a series of tris(2-aminoethyl)amine (tren)-based tris(phosphinimine) ligands (R3P3tren) and their coordination to transition metals. The phosphinimine moieties contained in these ligands are best represented by a zwitterionic resonance picture in which an anionic charge is positioned on …

Photodynamic Therapy Of Inorganic Complexes For The Treatment Of Cancer, Chloe B. Smith, Lindsay C. Days, Duaa R. Alajroush, Khadija Faye, Yara Khodour, Stephen J. Beebe, Alvin Holder

Chemistry & Biochemistry Faculty Publications

Photodynamic therapy (PDT) is a medicinal tool that uses a photosensitiser and a light source to treat several conditions, including cancer. PDT uses reactive oxygen species (ROS) such as cytotoxic singlet oxygen ¹O₂ to induce cell death in cancer cells. Chemotherapy has historically utilized the cytotoxic effects of many metals, especially transition-metal complexes. However, chemotherapy is a systemic treatment so all cells in a patient's body are exposed to the same cytotoxic effects. Transition metal complexes have also shown high cytotoxicity as PDT agents. PDT is a potential localized method for treating several cancer types by using inorganic …

Thermal Atomic Layer Deposition Of Titanium Nitride Films: Synthesis And Characterization Of Novel Titanium Precursors, Anuththara Chalani Upeksha Abesinghe Arachchige

Wayne State University Dissertations

Due to the continuous miniaturization of microelectronic devices, robust deposition techniques are required which can provide continuous and conformal thin films even in high aspect ratio structures. Atomic Layer Deposition (ALD) is an excellent choice of deposition technique as it is capable of providing perfect film coverage. Because of its self-limited growth mechanism, ALD can afford sub-nanometer thickness control. Precursors used in ALD should be volatile, thermally stable at the deposition temperature, and highly reactive towards the co-regent. Traditionally, ALD has been used to grow metal oxide films. However, the microelectronics industry now demands ALD for metals and metal nitrides. …

Synthesis And Reactivity Of Metal Bis(Alkoxide) Complexes In Nitrene Coupling And Polymerization Of Polar Monomers, Duleeka Chamini Wannipurage

Wayne State University Dissertations

The nitrene homocoupling to produce azoarenes was done using two different iron (II) alkoxide complexes, Fe(OCtBu2(3,5-Ph2C6H3)2(THF)2 and Fe[OO]Ph(THF)2. Due to the steric bulkiness of HOCtBu2(3,5-Ph2C6H3 ligand, this complex exhibited selectivity for the bis(alkoxide) ligation; no tris(alkoxide) complexes were observed. As a result, both bulky and non-bulky aryl nitrenes are coupled with Fe(OCtBu2(3,5-Ph2Ph)2(THF)2, albeit the coupling of the less bulky substrates requires higher temperatures and longer reaction times. Stoichiometric reactions of Fe(OCtBu2(3,5-Ph2C6H3)2(THF)2 with non-bulky aryl azides led to the observation of the iron(III) tetrazene radical anion complexes, that can produce azoarene products after heating. Tetrazene complexes likely serve as a “masked …

Continuing The Metalation And Ring Closure Of Biliazine, Joshua Villers

Williams Honors College, Honors Research Projects

Continuing previous research conducted by Dr. Ziegler and his Graduate Students in which different metals were selected to metalate the compound Biliazine as well as finding metals that could be used to close the ring system in Biliazine.

The Effects Of Increasing Positively Charged Metal Ions Within Synovial Fluid, Kandisi Anyabwile

Williams Honors College, Honors Research Projects

Osteoarthritis is a degenerative joint disease that affects 10% of men and 13% of women over age of 60. It is the degradation of the cartilage between two bones; obesity, age, overuse, or injury are major contributors to the development of this disease. The joint is incapsulated by the synovial sac filled with a viscous solution that aids in lubrication referred to as synovial fluid. If the synovial sac is ruptured due to injury, positive ions (K⁺, Na⁺, Ca²⁺, and Fe³⁺) may affect viscoelastic properties within the sac. The purpose of this …

Synthesis And Characterization Of Redox Non-Innocent Ligand Supported Transition Metal Complexes, Adriana Marie Lugosan

Dissertations

Catalysis is an integral part of society, which is often taken for granted. Over the past few years, there has been an increased effort to develop catalysts that are more environmentally friendly, selective, and energy efficient. This work focuses on the development of novel complexes made from a carefully designed non-innocent ligand together with earth-abundant and cost-effective transition metals that can be used to understand fundamental inorganic chemistry principles and serve as model systems. The work reported within validates the utility of this novel class of redox non-innocent ligand to form metal complexes with interesting properties, such as a non-porphyrin …

Cobalt, Molybdenum, And Nickel Complexes, Natural Zeolites, Epoxidation, And Free Radical Reactions, Nicholas K. Newberry

Dissertations, Master's Theses and Master's Reports

Chapter 2 is based on the synthesis and study of the compounds of the bidentate ligand ((5-phenyl-1H-pyrazol-3-yl)methyl)phosphine oxide with molybdenum and cobalt as the transition metal. The complexes were analyzed via FTIR, NMR, UV-Vis, Fluorescence Spectroscopy, TGA, DFT, and XRD. Chapter 3 resulted in the synthesis of the complexes [Ni(II)SSRRL](PF6)2 and [Ni(II)SRSRL](Cl)(PF6) of which [Ni(II)SRSRL](Cl)(PF6) had not been previously analyzed. Both products were analyzed via FTIR, NMR, UV-Vis, CV, DFT, and XRD. Chapter 5 contains the results of the characterization and modification of 4 natural zeolites (AZLB-Na, AZLB-Ca, NM-CA, NV-Na) from the United States in an attempt to increase the …

Multi-Level Analysis Of Atomic Layer Deposition Barrier Coatings On Additively Manufactured Plastics For High Vacuum Applications, Nupur Bihari

Dissertations, Master's Theses and Master's Reports

While hardware innovations in micro/nano electronics and photonics are heavily patented, the rise of the open-source movement has significantly shifted focus to the importance of obtaining low-cost, functional and easily modifiable research equipment. This thesis provides a foundation of open source development of equipment to aid in the micro/nano electronics and photonics fields.

First, the massive acceptance of the open source Arduino microcontroller has aided in the development of control systems with a wide variety of uses. Here it is used for the development of an open-source dual axis gimbal system. This system is used to characterize optoelectronic properties of …

The Rational Synthesis Of Lanthanum Manganite Nanomaterials For Magnetic Refrigeration Applications, Caitlin Hunt

Theses and Dissertations

Refrigeration systems for the cooling of commercial and residential buildings are a major drain on energy resources and source of greenhouse gas emissions. Magnetic refrigeration, which employs the magnetocaloric effect, has the potential to mitigate the energy drain and greenhouse gas emissions for air conditioning. In order to commercialize magnetic refrigerators, a material with a high magnetic entropy change, ΔS, near room temperature which is simple and inexpensive to create is needed.¹ Current options for this solid refrigerant are either expensive, difficult to synthesize, or have a ΔS or T_c (the Curie Temperature, where ΔS is maximized) below …

Accurate Quantitation Of Hexavalent Chromium For Reference Standard Certification And Quality Control Testing Using Speciated Isotope Dilution Mass Spectrometry, James E. Henderson

Electronic Theses and Dissertations

The ability to perform accurate, repeatable, and defensible elemental and molecular speciated analysis is immensely significant for measurements that support human health, environmental science, and industry. This is especially true since trivalent chromium [Cr(III)] is necessary for proper nutrition, while hexavalent chromium [Cr(VI)] is extremely toxic, genotoxic, and carcinogenic. The main challenges associated with speciated analysis are related to reactive species that are continuously transformed or converted to other species during sample processing. Accurate determination of Cr(III) and Cr(VI) species require a method that is capable of monitoring and correcting for interconversion, bias, and instrumental error. Traditional quantitative methods, such …

Nanomaterial Composites Based On Potassium Hexaniobate, Perovskites, And Iron Triazole Spin Crossover Complexes, Alexis A. Blanco

University of New Orleans Theses and Dissertations

Development of novel materials with sought after properties has been the forefront in the field of nanomaterials. Hybrid nanomaterial architectures, or nanocomposites, is an important subgroup within the material chemistry umbrella. One such example of nanocomposite systems is peapod-like structures that are composed of 0D nanoparticles (“peas”) and 2D nanosheets (“pods”). Nanopeapods may display unique properties that were not attainable within individual components. BaTiO₃ nanoparticles can be produced using solvothermal methods (20 h) in the presence of Ba(NO₃)₂, titanium (IV) butoxide, and oleic acid as the surfactant. Synthesis parameters were modified to allow for both …

Fluorinated Phthalonitriles And Phthalocyanines: Synthesis And Spectroscopic Properties, Marius Pelmus

Seton Hall University Dissertations and Theses (ETDs)

Since their discovery at the beginning of the 20^th century, phthalocyanines (Pc) have come a long way; today they are replacing the porphyrins (natural products) in most of their applications. The functionalization of the organic macrocycle, the use of different metals, and the change of the axial ligands resulted in Pc applications in a wide range of fields, ranging from photochemistry, paints, catalysis, to fuel cells and cosmetic products.

In Dr. Gorun’s group was developed a series of electron-deficient Pcs that benefit from a Teflon-like chemical shield, meant also to break the π-π interactions, namely the F₆₄PcM …

A Library Of Low Molecular Weight Fluorescent Probes For The Detection Of Cu(Ii) And Fe(Iii) Ions, Ashley Johnson

Dissertations

This dissertation reports the synthesis and photophysical properties of a family of rhodamine dyes (compounds 3.9-3.13 and 4.6). The rhodamine dyes are prepared in two steps, and fully characterized by ESI-MS (Low and High resolution), X-Ray crystallography, NMR spectroscopy, and FT-IR spectroscopy. The coordination environment of the low molecular weight fluorescent probes (LMFPs) was systematically changed to investigate the thermodynamic behavior between the LMFPs and an array of metal ions (Cu²⁺, Fe²⁺, and Hg²⁺ ions) in protic and aprotic solvent systems. Upon coordinating to metal ions, the π-conjugation of the LMFPs changed, resulting in …