Inorganic Chemistry Commons^™

Visible Light Generation And Mechanistic Investigation Of High-Valent Metal-Oxo Species Supported By Different Ligands, Seth Ellis Klaine

Masters Theses & Specialist Projects

Numerous transition metal catalysts have been designed as biomimetic model compounds for the active site of metalloenzymes found throughout Nature, most notably cytochrome P450 monooxygenases that carry out the oxidative transformations of organic substrates with near-perfect chemo-, regio-, and stereo-selectivity. The primary active oxidants in catalytic and enzymatic cycles are fleeting high-valent metal-oxo intermediates where the oxo ligand can transfer to an organic substrate in a process known as oxygen atom transfer (OAT).

In the present work, porphyrin-manganese(III), salen-chromium(III), and salenmanganese( III) derivatives were successfully synthesized and spectroscopically characterized using 1H NMR and UV-Vis spectroscopies. A facile photochemical approach was …

Synthesis And Catalytic Oxidation Of Organic Substrates By Light-Harvesting Metalloporphyrins, Christian Alcantar

Masters Theses & Specialist Projects

note: Some notation in this abstract may not appear exactly as formatted in the thesis.

In this work, ruthenium, iron, and manganese light-harvesting metalloporphyrins have been successfully synthesized to serve as biomimetic models of the active site of Cytochrome P450 for the development of a green and efficient oxidation catalyst. The covalent introduction of light-harvesting boron-dipyrrin (BODIPY) fluorophores on the porphyrin macrocycle allows for the absorption of a broader range of visible light in addition to that captured by the porphyrin aromatic system alone. It is expected that this core-antenna system will increase the absorbed light energy and transfer it …

Characterization Of Uranium, Lead, And Rare Earth Element Pollution In Natural Soils And Sediments, Hope Rasmussen

Civil and Environmental Engineering Theses and Dissertations

Heavy metals in the environment add to the global burden of pollution, negatively impacting public health and ecosystem resilience. This study included projects regarding uranium (U), lead (Pb), and rare earth elements (REE) in natural samples, due to their known toxicity, ubiquity, and relevance in context to recent pollution trends. The first project focused on testing the potential of using a hydroxyapatite product as a remediation solution for U-contaminated groundwater and soil at an EPA Superfund site. The results showed that the U was sequestered in a highly crystalline mineral form within the solids, guiding the EPA to specify the …

Interactions Of Organic Fluorophores With Plasmonic Surface Lattice Resonances, Robert J. Collison

Dissertations, Theses, and Capstone Projects

It is common knowledge that metals, alloys and pure elements alike, are lustrous and reflective, the more so when a metal surface is flat, polished, and free from oxidation and surface fouling. However, some metals reflect visible light, in the 380 nm to 740 nm range of wavelengths, much more strongly than others. In particular, some metals reflect wavelengths in certain portions of the ultraviolet (UV), visible, and near-infrared (NIR) regime, let us say 200 nm to 2000 nm, while absorbing light strongly in other segments of this range. There are several factors that account for this difference between various …

Coastal Watershed Monitoring And Management: Geomorphology, Geochemistry, And Hydrologic Modeling Of Los Peñasquitos Creek, Ca, Ravleen Khalsa-Basra

Theses

Rivers in semi-arid climates are directly influenced by local geographic and hydrologic conditions and impacted by modifications to hydrology via urbanization. Changes can influence erosion, morphology, habitat sustainability, and watershed health. In highly urbanized southern California coastal regions, these rare open spaces provide vital ecosystem services. Los Peñasquitos Creek in San Diego County is one such watershed. Using stream surveying and laboratory methods we quantified channel characteristics, grain size distribution, total metal concentration [M], organic carbon (%OC), and phosphate to longitudinally characterize the creek for improved management. Results identified three distinct reaches in the watershed (upper, middle, lower). Downstream, depth …

Water Spines And Networks In G-Quadruplex Structures, Kevin Li , '22, Liliya A. Yatsunyk, S. Neidle

Chemistry & Biochemistry Faculty Works

Quadruplex DNAs can fold into a variety of distinct topologies, depending in part on loop types and orientations of individual strands, as shown by high-resolution crystal and NMR structures. Crystal structures also show associated water molecules. We report here on an analysis of the hydration arrangements around selected folded quadruplex DNAs, which has revealed several prominent features that re-occur in related structures. Many of the primary-sphere water molecules are found in the grooves and loop regions of these structures. At least one groove in anti-parallel and hybrid quadruplex structures is long and narrow and contains an extensive spine of linked …

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 …

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. …

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 …

Synthesis Of A Series Of Ag(I)-Nhc Complexes For Future Antibacterial Studies, Alyssa Malto

Honors Program Theses

For thousands of years, silver (Ag) has been widely used for medicinal purposes due to its broad-spectrum antimicrobial properties. While medicinal silver usage declined with the advent of antibiotics, there has been a renewed interest in therapeutic silver coordination compounds to combat the spread of antibiotic resistance. N-heterocyclic carbenes (NHCs) are promising ligands for silver metallodrugs due to their wide structural variety that allows for tunability of the complex’s overall steric and electronic properties and previously established bioactivity against various pathogens and cancer cell lines. There is potential for efficacy against biofilms, a type of microbial growth pattern that is …

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 …

Synthesis And Characterization Of A Two Station Starburst Pseudorotaxane, Janaka Prasad Kaviraj Kavikarage

Masters Theses

Mechanically interlocked molecules (MIMs) are arranged with mechanical bonds. These molecules cannot be separated without breaking the required covalent bonds. There are different kinds of MIMs, such as rotaxanes, catenanes, suitanes, borromean rings, and molecular knots. These MIMs are stabilized by non-covalent interactions such as hydrogen bonds, π-π stacking, and ion-dipole interactions. Dialkylammonium ions, bis(pyridinium)ethane dications, viologen species, and naphthalene diimide π-deficient groups are typical examples of recognition motifs for crown ethers.

In the research described here, we synthesized a new axle, based on a combination of benzobis(imidazolium) (BBI) and viologen species. The axle contains two recognition sites: one is …

A Novel Palladium Bodipy Photocatalyst For Sonogashira Carbon-Carbon Cross-Coupling, Prahadeesh Nagaretnam

Masters Theses

No abstract provided.

Functionalization Of Novel Pp5 Inhibitors, Hope P. Hill

Honors Theses

The overexpression of protein phosphatase 5 has been correlated to tumor cell reproduction making it a candidate for small molecule drug therapy. Selective and potent inhibition of protein phosphatase 2A (PP2A) enzyme has been previously achieved through the development of the molecule fostriecin with key functionality being a lactone and unsaturated linear chain. The large synthetic overhead of fostriecin has led to exploration of other small molecule inhibitors that could mirror fostriecin’s interaction with the active site in the catalytic domain of PP5. The naturally occurring inhibitor, cantharidin, is functionalized with an epoxy containing eleven carbon chain to optimize binding …

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 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 …

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.

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 …

Experimental Exploration Of Shared Magnetic Phases Between Diverse Systems Of Iron-Pnictide Superconductors, Ryan Scott Stadel

Graduate Research Theses & Dissertations

The exciting field of iron-pnictide superconductors offers unique opportunities for studying the relationship between magnetism and unconventional superconductivity. This is vital to developing an understanding of the microscopic origin of high-temperature superconductivity, which is itself an important step in harnessing such a potentially revolutionary technology.

Polycrystalline and crystalline samples are synthesized over a diverse collection of related iron-pnictide systems including (Ca,Sr,Ba)1-xNaxFe2As2, Ba(Fe1-xCox)2As2 (122s), and LaFeAs1-xPxO, and TbFeAs1-xPxO (1111s). These compounds are characterized through various types of neutron and x-ray diffraction on multiple instruments, as well as muon spin resonance, and magnetic susceptibility measurements.

A thorough investigation into the conditions under …

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 (ETD)

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, …

Conformational Modulation Of Α-Helical N-Acetylated Α-Synuclein, Ricardo Fernandez

Theses and Dissertations

Human N-acetylated α-synuclein (^NAcαSyn) has long been accepted as an intrinsically disordered protein (IDP) predominantly found in terminal nerve regions in healthy subjects. ^NAcαSyn structural fluidity enables the formation of transient or dynamic assemblies. Some of these assemblies may serve functional, yet undefined purposes. ^NAcαSyn is highly susceptible to the surrounding environment, leading to misfolding under high cytosolic oxidative stress conditions, which in turn assemble in the form of toxic oligomers or amyloid fibrils. These ^NAcαSyn inclusions along with their accretion and migration within neurons, are pathological hallmarks of Parkinson’s disease (PD), dementia, and multiple …

Streptococcus Sanguinis: The Good, The Bad, And The Metal-Binding Lipoprotein, Cody Murgas

Theses and Dissertations

Streptococcus sanguinis is an opportunistic bacterium living beneficially in the human mouth. When S. sanguinis gains access to the bloodstream, it can result in colonization on damaged tissue and generate heart valve vegetations that can develop into infective endocarditis. It has been suggested that Mn and Fe are cofactors in the pathogenic capacity of this bacterium, and that these redox active metals are imported by the metal binding lipoprotein S. sanguinis adhesin B (SsaB). The SsaB lipoprotein is an integral part of SsaACB, an ATP-binding cassette (ABC) transport system in S. sanguinis. When SsaB is deleted, the resulting strain displays …

Design, Synthesis, And Anticancer Properties Of Ru(Ii) Complexes With Organometallic, “Expanded” Bipyridine, And O,O’-Chelating Ligands, Raphael Ryan

Theses and Dissertations--Chemistry

Cancer is a worldwide public health crisis that requires new and improved drugs to be developed to extend survival rates and improve quality of life for the patient. Platinum-based drugs are used in approximately 50% of cancer treatment regimens. These drugs are highly effective in many kinds of cancer; however, cancers can develop platinum resistance and these drugs have troubling side effects that reduced their use and efficacy. To overcome these disadvantages, many other metals have been studied for their anticancer properties. Notably, the anticancer properties of ruthenium-based agents have drawn considerable attention with multiple ruthenium complexes entering clinical trials. …

Metal Complexes Of Bis(Pyrazolyl)Methane-Based Ditopic Ligands, Pubudu Nuwan Perera Hapuarachchige

Masters Theses

No abstract provided.

Developing Synthetic Strategies For Multifaceted Applications Of Stable Gold-Based Complexes, Randall Tyler Mertens

Theses and Dissertations--Chemistry

Development of stable gold-based complexes has been a rapidly advancing field due to the popularity of gold complexes, particularly for use in biomedical research and catalytic transformations. Given that auranofin, a gold(I) complex with FDA approval for the treatment of rheumatoid arthritis is used in the clinic, the development of stable gold-based molecules of clinical relevance is urgently needed. Herein are reported, synthetic strategies used for the development of new classes of gold(I) and gold(III) complexes for advancement in mitochondrial modulation for use as chemotherapeutics as well as application to gold catalysis due to the unique geometry of complexes presented …

Generation, Characterization, And C-H Bond Activation Reactivity By Mononuclear High-Valent Cobalt(Iv) And Nickel(Iv) Non-Oxo Complexes, Yubin Maria Kwon

Graduate Student Theses, Dissertations, & Professional Papers

The study of terminal high-valent transition metal-oxo complexes has increased significantly over the years as it is believed that they are key reactive intermediates for a wide range of biological and industrial catalytic processes. These complexes are powerful oxidants for the activation of strong C-H bonds. The chemical and physical properties of these complexes remain elusive. It is therefore desirable to study the properties and function of these complexes through synthetic models. There have been many efforts and reports of synthetic high-valent metal-oxo complexes of early and middle transition metals (up to group 8 on the Periodic Table of Elements), …

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 …

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 …