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Associations Between Social Determinants Of Health And Mental Health Disorders Among U.S. Population: A Cross-Sectional Study, S. Tanarsuwongkul Jan 2025

Associations Between Social Determinants Of Health And Mental Health Disorders Among U.S. Population: A Cross-Sectional Study, S. Tanarsuwongkul

Faculty Publications

Aims

The impact of social determinants of health (SDOH) on mental health is increasingly realized. A comprehensive study examining the associations of SDOH with mental health disorders has yet to be accomplished. This study evaluated the associations between five domains of SDOH and the SDOH summary score and mental health disorders in the United States.

Methods

We analyzed data from a diverse group of participants enrolled in the All of Us research programme, a research programme to gather data from one million people living in the United States, in a cross-sectional design. The primary exposure was SDOH based on Healthy …


Photolysis And Sublimation Chemistry Of Ammonium Cyanide With Relevance To Cometary Environments, O. H. Wilkins, K. M. Yocum, Vincent J. Esposito, E. Harel, S. N. Milam, P. A. Gerakines Jan 2025

Photolysis And Sublimation Chemistry Of Ammonium Cyanide With Relevance To Cometary Environments, O. H. Wilkins, K. M. Yocum, Vincent J. Esposito, E. Harel, S. N. Milam, P. A. Gerakines

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Bulk nitrogen is depleted in solar system objects, including the terrestrial planets, chondritic meteorites, and comets. Recently, it was suggested that cometary nitrogen may be locked up in ammonium salts—ionic solids comprising ammonia (NH3) and an acid such as hydrogen cyanide (HCN)—based on Rosetta/ROSINA data from comet 67P/Churyumov–Gerasimanko. Among the proposed salts to have been found in 67P were ammonium cyanide (NH4CN) and ammonium cyanate (NH4OCN), which were inferred from identifying HCN, cyanamide (NH2CN), and isocyanic acid (HNCO) in the mass spectrometry data collected in the coma of 67P. However, the relationship …


Tribological, Thermal, Kinetic, And Surface Microtextural Characterization Of Prime P-Type <100> Silicon Wafer Cmp For Direct Wafer Bonding Applications, Michelle Yap, Catherine Yap, Yasa Sampurno, Glenn Whitener, Jason Keleher, Len Borucki, Ara Philipossian Jan 2025

Tribological, Thermal, Kinetic, And Surface Microtextural Characterization Of Prime P-Type <100> Silicon Wafer Cmp For Direct Wafer Bonding Applications, Michelle Yap, Catherine Yap, Yasa Sampurno, Glenn Whitener, Jason Keleher, Len Borucki, Ara Philipossian

Chemistry Department Faculty Articles

We investigated the tribological, thermal, kinetic, and surface microtextural characteristics of chemical mechanical polishing (CMP) of 300 mm p-type <100> prime silicon wafers (and their native oxide) at various pressures, sliding velocities, and starting platen temperatures. Results showed the dominant tribological mechanism for both native oxide and silicon polishing to be boundary lubrication. Using frictional data, we pinpointed the exact time that corresponded to the total removal of the native oxide and the onset of silicon polishing. This allowed us to separately characterize removal rates of each layer. For native oxide, while the rate depended on temperature, the presence of a …


Targeting Streptococcus Mutans Diadenylate Cyclase For The Prevention Of Dental Caries, Edwin Miguel Rojas Jan 2025

Targeting Streptococcus Mutans Diadenylate Cyclase For The Prevention Of Dental Caries, Edwin Miguel Rojas

All ETDs from UAB

Streptococcus mutans (S. mutans) is the primary etiological agent involved in the initiation and progression of dental caries. S. mutans forms robust biofilms on the tooth surface, and current preventative treatments, such as oral rinses, eliminate both pathogenic and commensal oral species. Therefore, there is an urgent need for therapeutics which selectively inhibit S. mutans biofilms while keeping the oral microbiome intact. The diadenylate cyclase (DAC) enzyme in S. mutans plays a key role in biofilm formation. DAC converts adenosine triphosphate (ATP) into cyclic di-AMP (c-di-AMP), a secondary messenger involved in several cellular pathways. Increased levels of c-di-AMP have shown …


Development And Characterization Of Sodium Alginate-Based Active Edible Films Functionalized With Olive Mill Wastewater Extract, Nassima Hadri, Mohamed Didi Ould El-Hadj, Zineb Mahcene, Fatih Bozkurt, Rusen Metin Yildirim, Youcef Rahmani, Aicha Tedjani, Muhammet Arici Jan 2025

Development And Characterization Of Sodium Alginate-Based Active Edible Films Functionalized With Olive Mill Wastewater Extract, Nassima Hadri, Mohamed Didi Ould El-Hadj, Zineb Mahcene, Fatih Bozkurt, Rusen Metin Yildirim, Youcef Rahmani, Aicha Tedjani, Muhammet Arici

Karbala International Journal of Modern Science

Phenolic compounds from olive mill wastewater (PCO) of Algerian origin were used to produce sodium alginate-based active films using the casting method. The effects of adding various concentrations of PCO (0%, 0.1%, and 0.2% w/v) were evaluated regarding the molecular, morphological, thermal, physicochemical, optical, barrier, biodegradability, antimicrobial, and antioxidant properties of the alginate films. The FTIR and SEM results elucidated the development of a coherent cross-linked structure attributed to hydrogen bonding interactions between PCO and alginate chains. Consequently, the films exhibited enhanced crystallinity and thermal stability, as revealed by DSC analysis. Moreover, PCO addition positively influenced several film properties, including …


Biofilm-Based Biomonitoring Of Treated Wastewater Using Bacillus Thuringiensis: Toward Sustainable Water Reuse, Bidisha Roy Sengupta, Kefa K. Onchoke, Olabisi O. Ogunlewe, Robert Friedfeld Jan 2025

Biofilm-Based Biomonitoring Of Treated Wastewater Using Bacillus Thuringiensis: Toward Sustainable Water Reuse, Bidisha Roy Sengupta, Kefa K. Onchoke, Olabisi O. Ogunlewe, Robert Friedfeld

Faculty Publications

No abstract provided.


Mechanism Of Napthenic Acid Binding To Dissolved Organic Matter, Clarissa Jules Jan 2025

Mechanism Of Napthenic Acid Binding To Dissolved Organic Matter, Clarissa Jules

Theses and Dissertations

The oil sands in Alberta, Canada are being destroyed by oil extraction because remediation methods have proven largely ineffective. One toxic byproduct of oil extraction is a family of cyclical surfactant organic acids known as naphthenic acids (NAs). They are toxic to aquatic life, including fish, frogs, and aquatic birds. It is suspected that NAs bind to humic acid, a major organic component of soil, in dissolved organic matter in natural water, making them difficult to remove by conventional remediation methods. This problem prompts the following question: what is the binding mechanism between NAs and humic acid when dissolved in …


Artificial Intelligence In Enzyme Engineering, Margret Pagare Jan 2025

Artificial Intelligence In Enzyme Engineering, Margret Pagare

Seton Hall Biochemistry II Annals of Student Reviews

No abstract provided.


Artificial Intelligence In Aptamer Design: Current Research In Machine Learning, Jennifer L. Matthews Jan 2025

Artificial Intelligence In Aptamer Design: Current Research In Machine Learning, Jennifer L. Matthews

Seton Hall Biochemistry II Annals of Student Reviews

No abstract provided.


How Ai Has Improved And Built Upon Previous Methods In Determining Protein Structures And Folding, Alexander J. Bulsiewicz Jan 2025

How Ai Has Improved And Built Upon Previous Methods In Determining Protein Structures And Folding, Alexander J. Bulsiewicz

Seton Hall Biochemistry II Annals of Student Reviews

No abstract provided.


Joanne Stubbe And The Mechanistic Study Of Ribonucleotide Reductases, Madysen York Jan 2025

Joanne Stubbe And The Mechanistic Study Of Ribonucleotide Reductases, Madysen York

Natural Sciences Student Research Presentations

To catalyze the formation of deoxyribonucleotides from ribonucleotides, the enzyme has to remove an hydroxyl from the ribose sugar part of the molecule (circled in in green) (“Ribonucleotide Reductase”).

The problem is that hydroxyl doesn’t naturally want to break from the base it is attached to, leaving many researchers unable to discern the chemical process going on inside these enzymes that make the bond break possible (Strauss).


Mary Lowe Good And The Development Of Catalytic Solutions For Industrial Processes, Eleanor Heller-Walker Jan 2025

Mary Lowe Good And The Development Of Catalytic Solutions For Industrial Processes, Eleanor Heller-Walker

Natural Sciences Student Research Presentations

To study catalysts, Good used Mössbauer spectroscopy, a nuclear technique that measures how atoms absorb and emit gamma rays (“Mössbauer Spectroscopy”). This method helps scientists identify oxidation states, chemical environments, and structural changes in metal containing materials, especially iron.

This data revealed exactly how active metal sites in catalysts behave when exposed to exhaust gases, for example, when carbon monoxide (CO) or nitrogen oxides (NOₓ) contact the surface of the metal.


Mass Spectrometry Combined With Chemical Biology To Study Human Ailments, Eric Thomas Jacquerio Davis Jan 2025

Mass Spectrometry Combined With Chemical Biology To Study Human Ailments, Eric Thomas Jacquerio Davis

Wayne State University Dissertations

Post-translational modifications (PTMs) are essential as chemical changes that regulate protein function, activity, stability, interactions, and localization after protein synthesis. PTMs, such as phosphorylation, acetylation, and ubiquitination, can activate or deactivate proteins, influence their interactions with other molecules, and determine their cellular location. This regulation is vital for numerous biological processes, such as cell cycle control, signal transduction, and gene expression. Abnormal PTMs are linked to various diseases in humans, including parasitic infection, blood disorders, cancers, and neurodegenerative diseases, making their study crucial for understanding disease mechanisms and developing targeted therapies. In the Pflum lab, we are interested in the …


Development And Characterization Of Polysaccharide-Based Controlled Drug Delivery Platforms, Amanda Pepler Jan 2025

Development And Characterization Of Polysaccharide-Based Controlled Drug Delivery Platforms, Amanda Pepler

Open Access Dissertations

Drug delivery research focuses on overcoming challenges in patient treatment. Most therapeutics are delivered systemically through oral or intravenous routes. However, these administration methods are often inefficient due to therapeutic hydrophobicity, poor bioavailability, and liver metabolic clearance, necessitating frequent dosing. When treatment plans require frequent dosing, patients experience significant fluctuations in therapeutic concentration in the bloodstream, which can increase adverse side effects. These factors contribute to low patient compliance. Therefore, the core focus of drug delivery research is to develop new administration routes for therapeutics. Drug delivery systems (DDS) that can target therapeutics to a localized region offer advantages over …


Copper-Based Oxide Semiconductors: Transparent Conductors And Ternary Alloys, Abhishek Rawat Jan 2025

Copper-Based Oxide Semiconductors: Transparent Conductors And Ternary Alloys, Abhishek Rawat

Chemistry & Biochemistry Dissertations - Archive

This dissertation explores the strategic design and development of copper-based metal oxide semiconductors for photoelectrochemical (PEC) and optoelectronic applications, with a focus on advancing materials for sustainable energy technologies. Through a comprehensive investigation into copper vanadates and copper oxides, the work aims to understand and enhance charge transport, light-harvesting capabilities, and electronic structure modulation. The research integrates fundamental materials chemistry with applied photoelectrochemical studies to uncover the role of copper's d-electrons in mid-gap state formation, multifunctionality through electronic structure tuning, and the development of low-temperature transparent conductive oxides.

In chapter 2, we have discussed the attributes of copper metavanadate (CuV …


Reducing Friction In Machine Oil Via Cesium-Hybridized Graphene Oxide Quantum Dot Additives, Islam Gomaa, Sherief Elsoudy, Maryam Galal, Ahmed Azim Jan 2025

Reducing Friction In Machine Oil Via Cesium-Hybridized Graphene Oxide Quantum Dot Additives, Islam Gomaa, Sherief Elsoudy, Maryam Galal, Ahmed Azim

Nanotechnology Research Centre

Friction and wear are among the most common causes of energy loss and component failure in mechanical systems, accounting for around 20–30% of total global energy consumption. Conventional lubricants fail to provide consistent performance in harsh conditions due to inadequate additive dispersion, agglomeration, and restricted surface reactivity. Recent advances in nanomaterial-based lubricants have shown promise, but it remains difficult to achieve significant friction and wear reduction at low additive concentrations while preserving stability. In this study, we synthesized and tested cesium-hybridized graphene oxide quantum dots (Cs-GOQDs) as novel lubricant additives. When incorporated into machine oil at 0.1 wt%, Cs-GOQDs reduced …


Hydrogen Peroxide Production From Light-Driven Water Oxidation Via Nickel Oxide-Titanium Dioxide Heteronanocrystals, Mahfuz Ahammed Swadhen Jan 2025

Hydrogen Peroxide Production From Light-Driven Water Oxidation Via Nickel Oxide-Titanium Dioxide Heteronanocrystals, Mahfuz Ahammed Swadhen

Dissertations and Theses

High dependence on fossil fuels for energy carries risks for the environment, health, energy, and geopolitical stability. One of the solutions to address this is solar energy utilization, and the use of semiconductors for photocatalytic water splitting is a tantalizing prospect. An n-type semiconductor TiO2 combined with p-type NiO producing a heteronanojunction shows effective light-driven oxidation of H2O into H2O2. We developed a synthetic method to attach NiO nanoparticles on the surface of anatase TiO2 nanorods. We characterized the materials with UV-visible spectroscopy, powder X-ray diffraction, and electron microscopy. We immobilized the HNCs on fumed silica and removed organic surfactants …


Verification Of Real-Time Smoke Simulations: A Case Study On Early Summer North American Wildfire Events, Daniel Bonilla Jan 2025

Verification Of Real-Time Smoke Simulations: A Case Study On Early Summer North American Wildfire Events, Daniel Bonilla

Pitzer Senior Theses

As wildfire intensity and frequency escalate in times of unprecedented climate change and severe droughts, it is important to enhance forecasting models that accurately and efficiently predict wildfire smoke movement. NOAA’s experimental Rapid-Refresh Forecasting System with Smoke and Dust (RRFS-SD) aims to improve upon the High-Resolution Rapid Refresh- Smoke (HRRR-Smoke), by extending the domain to include all of North America and incorporating new developments in physics and wildfire parameterizations. Our work explores the process of adding satellite Aerosol Optical Depth (AOD) data, through AERONET, as an additional method of verification of the RRFS-SD experimental model. Using a case study on …


Eugenol Loaded Calcium Citrate Particle As A Ph Triggered Drug Release System And A Reducing Agent For Au (Iii), Sadia Afrin Jan 2025

Eugenol Loaded Calcium Citrate Particle As A Ph Triggered Drug Release System And A Reducing Agent For Au (Iii), Sadia Afrin

Dissertations and Theses

The study demonstrated that eugenol affects the morphology of calcium citrate particles during their formation, as confirmed by SEM micrography and PXRD analysis. Coating of eugenol loaded calcium citrate particles (CaCit MPs) with casein improves their known pH-dependent drug release profile, as confirmed by UV absorption spectroscopy. The casein-coated eugenol-loaded CaCit MPs (CCaCit(eu) MPs) can effectively control and sustain drug release under different pH conditions, particularly at acidic pH values (4.8 and 5.5), which mimics the environment of tumor tissues. To further explore the biomedical applications of calcium citrate, a bulk nanostructured precursor to the known anti-cancer calcium citrate phosphate-based …


The Relevance Of Dnajb1 Protein Dimerization Against The Human Neurodegenerative Diseases, Erina Kotreli, Trang Le, Szymon Ciesielski Jan 2025

The Relevance Of Dnajb1 Protein Dimerization Against The Human Neurodegenerative Diseases, Erina Kotreli, Trang Le, Szymon Ciesielski

Dean's Leadership Council Library Research Prize

All biological functions in living organisms depend on the activity of proteins, long molecules that must twist and fold into specific shapes to become functional. A subset of proteins known as molecular chaperones is essential for maintaining cellular health by assisting other proteins in folding correctly and refolding those damaged by stress. When proteins misfold and clump together, they can form toxic aggregates linked to many neurodegenerative diseases, including Alzheimer’s disease (AD), one of the leading causes of death in the United States. In AD, these protein aggregates form organized, elongated structures referred to as amyloid-like fibrils, which damage neurons …


Structure–Property Relationships Mediated By Lone Pairs And Vacancies In Oxychalcogenides: A Combined Experimental And Theoretical Study, Hoa Hn Nguyen Jan 2025

Structure–Property Relationships Mediated By Lone Pairs And Vacancies In Oxychalcogenides: A Combined Experimental And Theoretical Study, Hoa Hn Nguyen

Chemistry & Biochemistry Dissertations - Archive

Structure–property relationships in some oxychalcogenide materials are strongly governed by the interplay between stereochemically active lone pairs and anion vacancy formation. Through a combination of density functional theory (DFT), synchrotron and neutron total scattering and optical characterization, this work elucidates how local symmetry breaking, chemical substitution, and vacancy dynamics influence electronic and optical behavior across several lone pair-containing systems. In crystalline TeO2, all three polymorphs exhibit wide band gaps with Te4+ 5s2 lone pairs contributing significantly near the valence band edge. Oxygen vacancy formation is thermodynamically favorable and induces asymmetric charge redistribution and enhanced polarizability, supporting …


Characterization And Leaching Feasibility Studies Of Copper Flue Dust For The Recovery Of Main And Trace Metals, Fardis Nakhaei, Marek Locmelis, Lana Alagha, Michael S. Moats, Carlos Eyzaguirre, Cory Smith Jan 2025

Characterization And Leaching Feasibility Studies Of Copper Flue Dust For The Recovery Of Main And Trace Metals, Fardis Nakhaei, Marek Locmelis, Lana Alagha, Michael S. Moats, Carlos Eyzaguirre, Cory Smith

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Although copper smelter dust (CSD) is classified as hazardous waste, it also serves as a valuable secondary resource, offering potential for the recovery of critical elements. In this study, CSD samples were collected from the waste heat boiler (WHB) and electrostatic precipitator (ESP) units connected to the flash smelting furnace at a copper smelter. The representative samples were extensively characterized by particle size, and chemical and mineralogical analyses. Following sample characterization, leaching experiments were performed to evaluate the potential extraction of Cu, Fe, As, Zn, Pb, In, Ga, and Ge from the flue dusts. Distilled water, H2SO4, and HCl were …


The Effect Of Polyethylene Glycol Surface Density Of Dense Brush Gold Nanoparticles On Insulin Fibrillation, Ethan Patrick Grier Jan 2025

The Effect Of Polyethylene Glycol Surface Density Of Dense Brush Gold Nanoparticles On Insulin Fibrillation, Ethan Patrick Grier

Graduate Theses/Dissertations

The development of various neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease has been linked to the fibrillation of various proteins within the brain. Parkinson’s disease is specifically linked to the fibrillation of α-Synuclein. During the fibrillation process, the proteins take the form of oligomers, and exposure to these oligomers has been linked to various cytotoxic and neurotoxic effects. Once the fibrillation process is complete, the fibrils made have been shown to be much less toxic than the oligomer stage. This fibrillation process is thermodynamically favorable and is largely irreversible, so one course of action for treatment of these …


Generational Exposures To Cerium Oxide Nanoparticles And Perfluorooctanesulfonic Acid Affect The Performance Of Daughter Plants, Preston Clubb Jan 2025

Generational Exposures To Cerium Oxide Nanoparticles And Perfluorooctanesulfonic Acid Affect The Performance Of Daughter Plants, Preston Clubb

Graduate Theses/Dissertations

The effects of parental stress on the performance of next generation exposed to another contaminant were investigated. Wheat was exposed to cerium oxide nanoparticles (CeO2-NPs) in first and second generations and exposed to perfluorooctanesulfonic acid (PFOS) in the third generation. Phenotypic or metabolic responses were assessed at 21-day (short-term exposure) or 90-day (long-term exposure) exposure periods. Biomass production, chlorophyll content, enzyme activity, and membrane damage were measured at short-term exposure, while elemental and PFOS concentrations, and grain metabolites were analyzed in long-term exposure. Results showed that continued exposures to CeO2-NPs and PFOS enhanced chlorophyll content but reduced concentrations of important …


Lc-Ms Discriminates Between Effects Of Sulfur Nanoparticles Vs Molybdenum Disulfide Nanoparticles On Lettuce (Lactuca Sativa), Mary Fakunle Jan 2025

Lc-Ms Discriminates Between Effects Of Sulfur Nanoparticles Vs Molybdenum Disulfide Nanoparticles On Lettuce (Lactuca Sativa), Mary Fakunle

Graduate Theses/Dissertations

Nanotechnology is gaining attention in agriculture, majorly due to their potential benefits in farming practices. Sulfur and molybdenum disulfide nanoparticles are reported to enhance plant growth, protection, and nutrient delivery. However, there is a need to understand how nano-fertilizers affect the metabolites and nutritional benefits of plants. Here, lettuce was cultivated under greenhouse in one of three treatments: control, 50 ppm S NPs, and 20 ppm MoS2 NPs. A method was developed on Liquid Chromatography – Mass Spectrometry (LC-MS) instrument to quantify the concentration of amino acids and antioxidants in the harvested lettuce plants. Inductively Coupled Plasma – Mass Spectrometry …


Tailoring Selected Aerogels To Targeted Applications, Stephen Yaw Owusu Jan 2025

Tailoring Selected Aerogels To Targeted Applications, Stephen Yaw Owusu

Doctoral Dissertations

Aerogels are ultra-lightweight, porous solid materials characterized by a three-dimensional nanostructured network. Owing to their exceptional physical and chemical properties, aerogels have garnered considerable attention within the materials science community and were recognized by IUPAC in 2022 as one of the top ten emerging technologies in chemistry. Although numerous aerogels have been synthesized, only a few have been effectively tailored for specific applications. Optimizing the properties of known aerogels for targeted uses remains challenging. This dissertation investigates strategies for tailoring aerogels derived from isocyanate-benzoxazine, benzodiazine, and phenolic resins to meet the requirements of various advanced applications. The approaches employed include …


Development Of Dual-Scan Nuclear Magnetic Resonance (Nmr) Pulse Programs For Spin-Lattice Relaxation Measurements, Zachary Mayes Jan 2025

Development Of Dual-Scan Nuclear Magnetic Resonance (Nmr) Pulse Programs For Spin-Lattice Relaxation Measurements, Zachary Mayes

Doctoral Dissertations

This research develops and refines the Split Inversion Pulse and Recovery (SIP R) methodology for spin-lattice relaxation (T₁) measurements in NMR spectroscopy. SIP R introduces a two-scan difference technique using a split inversion pulse sequence, where the 180° pulse is split into two 90° pulses phase-shifted with respect to each other. This approach simplifies data fitting, requiring only two parameters to extract T₁ values, compared to the traditional inversion-recovery method, which needs three. The SIP-R-DS and SIP-R-S adaptations extend this framework by incorporating selective NMR resonance excitations, enhancing its applicability to cross-polarization experiments and enabling unobstructed NOE measurements. These adaptations …


Epitaxial Growth Of Metal-Organic Framwork Thin Films By Electro-Conversion And Electrodeposition, Xiaoting Zhang Jan 2025

Epitaxial Growth Of Metal-Organic Framwork Thin Films By Electro-Conversion And Electrodeposition, Xiaoting Zhang

Doctoral Dissertations

Electrochemical epitaxy is a facile and inexpensive soft-solution process to fabricate highly ordered thin films. This research focuses on the epitaxial growth of metal-organic framework (MOF) thin films by electrochemical methods which include electro-conversion and electrodeposition.

First, an electrochemical conversion pathway was invented to achieve epitaxial MOF thin films. Epitaxial single-domain Cu-BTC(111) thin films were manufactured by electrochemical oxidation of Cu2O(111) films electrodeposited on single-crystal Au(111). The single-crystal-like Cu-BTC(111) thin films with out-of-plane and in-plane order provide well-aligned 3.5 Å triangular windows along the [111] direction. Cu-BTC(111) foils were fabricated from the Cu-BTC/Cu2O system by electrochemical …


Applications Of Tetramethyl-Guanidine Supported Cationic Transition Metal Sites Towards C─N Bond Construction Methodologies And [3+2] Cycloaddition Reactions, Suraj Kumar Sahoo Jan 2025

Applications Of Tetramethyl-Guanidine Supported Cationic Transition Metal Sites Towards C─N Bond Construction Methodologies And [3+2] Cycloaddition Reactions, Suraj Kumar Sahoo

Doctoral Dissertations

"We present a family of divalent cationic bipodal and tripodal M(II) reagents (M = Mn, Fe, Co) supported by superbasic tetramethyl-guanidinyl (TMG) residue framework with applications towards C─N bond construction methodologies. These cationic reagents possess unique characteristics since their enhanced Lewis acidity facilitates in situ elaboration of the primary nitrene-transfer product (aziridine). Indeed, further aziridine-ring opening and cycloaddition of several dipolarophiles (nitriles, alkenes, ketones) permits the three-component synthesis of valuable five-membered N-heterocycles, commonly found in pharmaceuticals and agrochemicals.

We undertake a more systematic study to unravel parameters that make certain divalent metal sites more suitable as catalysts for the in-situ …


Development Of Ligands And Metal Complexes With Weakly Coordinating Apical Elements And Their Application To Nitrene Insertion And Addition To C‒H And C=C Bonds, Meenakshi Sharma Jan 2025

Development Of Ligands And Metal Complexes With Weakly Coordinating Apical Elements And Their Application To Nitrene Insertion And Addition To C‒H And C=C Bonds, Meenakshi Sharma

Doctoral Dissertations

"We present a family of triangular coinage metal M3Cl3 complexes [M = Cu (I), Ag (I)] supported by antimony [Sb (III)], and bismuth [Bi (III)]-centered highly basic tetramethyl-guanidinyl [TMG3trphen-E] (E = Sb, Bi) ligand frameworks with their applications as catalysts toward the construction of C‒N bond through aziridination and amination reaction methodologies.

The [(TMG3trphen-Sb)Cu3(µ-Cl)3] catalyst gives better yields of aziridines with styrenes than [(TMG3trphen-Bi)Cu3(µ-Cl)3] with PhINTs as a nitrene source. However, the catalytic reactivity of both catalysts is enhanced by an electrophilic nitrene, PhINTces for …