Investigation Of Additives And Ingredients Of Bio-Resin For Visible Wavelength Laser-Induced Polymerization,
2023
Georgia Southern University
Investigation Of Additives And Ingredients Of Bio-Resin For Visible Wavelength Laser-Induced Polymerization, Patrick Riggs
College of Graduate Studies: Theses & Dissertations
Optical 3D printing is a branch of Additive manufacturing (AM) that utilizes low-waste production leading to efficient and rapid prototyping. Currently, this method of AM is associated with mainly petroleum-based resins. Bio-resin polymerization is an emerging research area for finding replacements for petroleum-based resins, but curing the resin with laser energy is not normally a practical use case. Current optical 3D printing uses lasers to cure liquid resins to form solid 3D objects in a layer-by-layer process which is time consuming, defect prone, and a leading limiting factor for high volume production; so, finding a way to incorporate bio-resin into …
Design And Synthesis Of Novel Antibiotics And Anticancer Agents Targeting Pharmaceutically Relevant Enzymes,
2023
Loyola University Chicago
Design And Synthesis Of Novel Antibiotics And Anticancer Agents Targeting Pharmaceutically Relevant Enzymes, Sebastian Flieger
Dissertations
Boron neutron capture therapy (BNCT) is a binary radiotherapeutic modality for cancer treatment, in which delivery agents containing 10B atoms are transported into tumor cells and then irradiated with low-energy thermal neutrons. Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases that are involved in the remodeling and degradation of all components of the extracellular matrix (ECM). Overexpressed levels of MMP activity have been implicated in several disease states including tumor growth and metastasis. We have appended a borane-rich carborane cluster onto MMP-targeting pharmacophores to enable delivery of 10B atoms to a tumor. Herein, we describe the molecular docking experiments …
Ultrasensitive Tapered Optical Fiber Refractive Index,
2023
Old Dominion University
Ultrasensitive Tapered Optical Fiber Refractive Index, Erem Ujah, Meimei Lai, Gymama Slaughter
Electrical & Computer Engineering Faculty Publications
Refractive index (RI) sensors are of great interest for label-free optical biosensing. A tapered optical fiber (TOF) RI sensor with micron-sized waist diameters can dramatically enhance sensor sensitivity by reducing the mode volume over a long distance. Here, a simple and fast method is used to fabricate highly sensitive refractive index sensors based on localized surface plasmon resonance (LSPR). Two TOFs (l = 5 mm) with waist diameters of 5 µm and 12 µm demonstrated sensitivity enhancement at λ = 1559 nm for glucose sensing (5-45 wt%) at room temperature. The optical power transmission decreased with increasing glucose concentration due …
High Figure Of Merit Spin Polarized Electron Sources Grown Via Mocvd,
2023
Old Dominion University
High Figure Of Merit Spin Polarized Electron Sources Grown Via Mocvd, Benjamin Belfore, Adam Masters, Deewakar Poudel, Greg Blume, Stephen Polly, Erdong Wang, Seth M. Hubbard, Marcy Stutzman, Joseph M. Grames, Matt Poelker, Matt Grau, Sylvain Marsillac
Electrical & Computer Engineering Faculty Publications
Spin polarized photocathodes are key to the future operation of electron accelerators such as the ones at Thomas Jefferson National Accelerator Facility and Brookhaven National Laboratory. Currently, these photocathodes come in short supply due to limited production by molecular beam epitaxy. By developing a process to implement similar structures using metal organic chemical vapor deposition, the availability of these devices can be increased. In this paper, we detail the implementation of recent photocathode advancements via metal organic chemical vapor deposition process and show an improvement in both polarization and quantum efficiency of our devices compared to those fabricated via molecular …
Copper-Catalyzed Dehydrogenative Decarboxylation Reactions Of Carboxylic Acids To Alkenes,
2023
West Virginia University
Copper-Catalyzed Dehydrogenative Decarboxylation Reactions Of Carboxylic Acids To Alkenes, Michael P. Stanton
Graduate Theses, Dissertations, and Problem Reports (ETD)
Linear alpha olefins (LAOs) are important building blocks in the production of linear low-density polyethylene, a plastic used in products such as shrink wraps, plastic bags, tubing, plasticizers, among others. Commercial methods for generating LAOs utilize ethylene oligomerization, but this method is reliant on fossil fuels and leads to unselective product formation. Synthesis of LAOs from renewable resources, namely carboxylic acids, by decarbonylative dehydration strategies has been well studied, however, this method has inherent drawbacks rooted in the formation of internal olefin side-products through isomerization pathways. With the goal of avoiding internal isomerization, this thesis explores a dehydrogenative decarboxylation strategy …
Enabling Technologies For Chemical Synthesis: I. Selective Microwave Heating; Ii. Synthesis And Regioselective Cyclotrimerizations Of Tethered 1,6-Diynes,
2023
West Virginia University
Enabling Technologies For Chemical Synthesis: I. Selective Microwave Heating; Ii. Synthesis And Regioselective Cyclotrimerizations Of Tethered 1,6-Diynes, Amir Tavakoli
Graduate Theses, Dissertations, and Problem Reports (ETD)
Reaction discoveries, method developments, and technology advancements lie at the heart of synthetic organic chemistry. These innovations are essential for creating and manipulating complex molecules, which are the building blocks of many important chemical compounds, including pharmaceuticals, materials, and agrochemicals. Here, we first describe new methods to prepare neopentylene-tethered (NPT) 1,6-diynes which are valuable substrates for reaction discovery and target-oriented synthesis, especially in benzannulation strategies toward illudalane natural products. NPT 1,6-diynes have been employed as coupling partners in cyclotrimerization reactions for the synthesis of highly substituted benzene rings which present a persistent challenge in chemical synthesis and are underrepresented scaffolds …
Enantioselective Dearomatization Facilitated By Non-Covalent Interactions Of N-Heterocyclic Carbene Catalysts And Pyridinium Salts,
2023
West Virginia University
Enantioselective Dearomatization Facilitated By Non-Covalent Interactions Of N-Heterocyclic Carbene Catalysts And Pyridinium Salts, Jack A. Patterson
Graduate Theses, Dissertations, and Problem Reports (ETD)
Dihydropyridines are a practical organic scaffold commonly used for their pharmaceutical properties. Nucleophilic dearomatization of pyridines has proven to be a useful method in obtaining dihydropyridines. By using N-heterocyclic carbene (NHC) organocatalysts, dihydropyridines can be synthesized with high regioselectivity of the 1,4 regioisomer over the 1,2- regioisomer but often with low enantioselectivity. By incorporating non-covalent interaction contact points, we hypothesize that enantioselectivity can be enhanced. By synthesizing numerous NHCs, each proposed to exhibit a different type of non-covalent interaction (i.e., hydrogen bonding or ion pairing), an understanding of the secondary interactions within this reaction system can be studied and …
Synthesis And Pharmacology Of Illudalic Acid And Analogous Chemical Structures,
2023
West Virginia University
Synthesis And Pharmacology Of Illudalic Acid And Analogous Chemical Structures, Robert Gaston Jr
Graduate Theses, Dissertations, and Problem Reports (ETD)
Natural products are the foundation of modern medicine and an inspiration for chemical innovation. Developing new synthetic strategies to complex natural products drives synthetic innovation and promotes pharmacological exploration. As bioactive secondary metabolites of fungi, illudalic acid and associated analogs have unrealized medicinal potential due to synthetic limitations. Illudalic acid is notably the first selective covalent inhibitor of the LAR-PTPs, a class of enzymes linked to many human illnesses, including stimulant addiction. The chemistry herein focuses on optimizing synthetic routes to illudalic acid and associated analogs toward exploring their pharmaceutical potential. We report a second-generation synthesis of illudinine (55% overall …
Investigations Into Indole Formation: Base-Mediated Formation Of N-Hydroxy- And N-Alkoxyindoles, Ancillary Ligand Development For Watanabe-Cenini-Söderberg Cyclization, And Total Synthesis Of Racemosin B,
2023
West Virginia University
Investigations Into Indole Formation: Base-Mediated Formation Of N-Hydroxy- And N-Alkoxyindoles, Ancillary Ligand Development For Watanabe-Cenini-Söderberg Cyclization, And Total Synthesis Of Racemosin B, Blaine Thomas Mcclay
Graduate Theses, Dissertations, and Problem Reports (ETD)
A novel, base-mediated cyclization was developed to form N-hydroxy- and N-alkoxyindoles from 2-(2-nitrophenyl)butenoates. Potassium tert-butoxide or sodium tert-pentoxide, with or without the in-situ addition of an electrophile, formed a multitude of N-hydroxy- and N-alkoxyindoles. The formation of these butanoate precursors was improved via a Barluenga coupling reaction. Novel 4,5,6,7-tetramethoxy-1,10-phenanthroline was utilized as an ancillary ligand within the Watanabe-Cenini-Söderberg reductive cyclization reaction conditions. These new reaction conditions produced high yields for sterically hindered 2-nitrostyrenes and the first synthesis of dilemmaone A using this reductive cyclization. Racemosin B was synthesized in a three-step process utilizing a …
2-Aminopyridyl Functionalized Scaffold As A Tool For Systematic Investigation Of B-Glucan Binding And Dectin-1 Activation,
2023
University of Montana
2-Aminopyridyl Functionalized Scaffold As A Tool For Systematic Investigation Of B-Glucan Binding And Dectin-1 Activation, Jasper Alinea Aquino
Graduate Student Theses, Dissertations, & Professional Papers
Tuberculosis (TB) – an infectious disease caused by Mycobacterium tuberculosis (Mtb) – remains an epidemic worldwide contributing to millions of deaths each year. Vaccination is possibly the best means of addressing this global threat. In recent years, synergistic Th1 and Th17 immune responses have emerged as the key players for a vaccine-induced protection against TB. There is currently no vaccine approved for humans that elicits a Th17-mediated immune response. C-Type Lectin Receptors (CLR), specifically Dectin-1, a pattern recognition receptor (PRR) of β-1,3-glucans (β-glucans) primarily from fungi cell walls, is known to induce a Th17-mediated response. The Th17 response upon binding …
Non-Traditional Methods For The Green Synthesis Of Fine Chemicals,
2022
University of Massachusetts Boston
Non-Traditional Methods For The Green Synthesis Of Fine Chemicals, Tara Renée Mooney
Graduate Masters Theses
Herein, the advancement of microwave-assisted flow synthesis is reviewed and the green nitration of arenes is investigated. First, microwave-assisted flow systems are described, followed by their synthetic and environmental applications. Microwave-assisted flow synthesis has been applied successfully in organic, inorganic, material, and biochemical syntheses as well as environmental applications such as water desalination and the removal of volatile organic compounds from the atmosphere. In the second part of the Thesis, the methodological development of the first catalyst and solvent-free nitration of m-xylene using only nitric acid is detailed. This environmentally friendly reaction proceeds without the use of harsh Brønsted acids, …
Palladium (Ii)-Catalyzed Selective Reduction Of 4’-(Phenylethynl)Acetophenone In The Presence Of A Formic Acid-Triethylamine Mixture,
2022
Department of Chemistry, Faculty of Science, Beirut Arab University
Palladium (Ii)-Catalyzed Selective Reduction Of 4’-(Phenylethynl)Acetophenone In The Presence Of A Formic Acid-Triethylamine Mixture, Suzanne Chayya, Akram Hijazi, Anis Daou, Ali Alaaeddine, Mohamad Sakr, Ghassan Younes, Mohammad El-Dakdouki
BAU Journal - Science and Technology
An efficient and straightforward palladium acetylacetonate-catalyzed hydrogen transfer of 4'- (phenylethynyl)acetophenone was developed in this study. Formic Acid was found to be the best hydrogen source in this catalytic system in the presence of triethylamine. Excellent conversions and selectivity were obtained in reducing the starting internal aromatic alkyne to either (E)-1-(4- styrylphenyl)ethanone or an interesting cyclic product, 1-(phenanthrene-3-yl)ethenone, over the ketone functional group present. Over-reduction was rarely seen. The reaction conditions were optimized in terms of the choice of the palladium catalyst, temperature, solvent, and the H-donor/base combination. Using this catalytic system, a one-step synthetic pathway of the …
Metallacycle-Mediated Cross-Coupling As An Enabling Tool For Studies In Carbocycle Synthesis And Functionalization,
2022
Dartmouth College
Metallacycle-Mediated Cross-Coupling As An Enabling Tool For Studies In Carbocycle Synthesis And Functionalization, Adam Barry Millham
Dartmouth College Ph.D Dissertations
Natural products, specifically complex, carbocyclic natural products, have served as the inspiration for novel methods development for decades. Over that time, metallacycle-mediated cross-coupling has arisen as a powerful means for the synthesis of fused carbocycles. This work details three methods for the synthesis and functionalization of carbocyclic motifs that have been enabled by Ti-mediated cross-coupling reactions. The first of these studies include a complementary method to the Pauson–Khand reaction for the synthesis of highly substituted cyclopentenones via Ti-mediated alkyne–β-ketoester coupling. The second project, a modern approach to steroidal tetracycles, will be discussed that features: (1) an alkoxide-directed metallacycle-mediated [2+2+2] annulation …
Development Of Novel Nucleophile-Intercepted Beckmann Fragmentations And Progress Toward The Total Synthesis Of 2(S)-Cathafoline,
2022
Dartmouth College
Development Of Novel Nucleophile-Intercepted Beckmann Fragmentations And Progress Toward The Total Synthesis Of 2(S)-Cathafoline, Evan M. Dunkley
Dartmouth College Master’s Theses
This thesis is comprised of two chapters, the first being the discovery of a novel nucleophile-intercepted Beckmann fragmentation of [2.2.1] indoline systems that resulted in highly stereo- and regioselective reactions. Chapter one details the exploration of this reaction as well as its relevant background information detailing its significance. Chapter two describes the application of the novel nucleophile-intercepted Beckmann fragmentation in the context of a total synthesis of akuammilline alkaloid 2(S)-cathafoline. While the target natural product was never synthesized, unpredicted reactivity resulted in interesting discoveries worthy of discussion.
Photocatalytic Anti-Markovnikov Hydroetherification Of Olefins,
2022
Binghamton University--SUNY
Photocatalytic Anti-Markovnikov Hydroetherification Of Olefins, Kimberly A. Loyer
Undergraduate Honors Theses
The development of olefin hydroetherification reactions via the addition of an alcohol nucleophile and hydrogen atom across an unsaturated carbon-carbon bond has remained a sought- after synthetic transformation. The formation of ethers via this methodology has traditionally required the use of transition metals and/or harsh conditions to catalyze the reaction and is challenging to make selective. However, the Nicewicz laboratory has since developed an anti- Markovnikov intramolecular hydroetherification of alkenols using photoredox catalysis. With the mechanism of this pivotal transformation—and of photoredox reactions in general—being largely unexplored mechanistically, the Hirschi lab implemented experimental 13C kinetic isotope effects (KIEs) and density …
The Chemistry And Catalytic Activity Of Dehydrogenative Silylation And Hydroboration Of Complexes Bearing Semirigid Ligands With Group 14 Elements,
2022
Mississippi State University
The Chemistry And Catalytic Activity Of Dehydrogenative Silylation And Hydroboration Of Complexes Bearing Semirigid Ligands With Group 14 Elements, Niroshani S. Abeynayake
Theses and Dissertations
Incorporation of silicon in the ligand backbone would yield electron-rich metal complexes upon coordination to transition metal complexes. The coordination chemistry of semirigid benzyl phosphines bearing a single or multiple phosphorus atoms and varying number of Si−H moieties has gained interest in recent years. This dissertation focuses on synthesizing silyl and germyl transition metal complexes of groups 9 and 10. Chapter II presents the synthesis of a family of four coordinated 14-electron rhodium complexes. The newly synthesized complexes were characterized in solution by multinuclear NMR spectroscopy and in the solid-state by single-crystal X-ray diffraction. These d6 complexes possess sawhorse …
The Design, Synthesis, And Investigation Into Small Molecule Modulators Of The Src Homology 2 Domain-Containing Inositol 5’-Phosphatase (Ship),
2022
Syracuse University
The Design, Synthesis, And Investigation Into Small Molecule Modulators Of The Src Homology 2 Domain-Containing Inositol 5’-Phosphatase (Ship), Shea Thomas Meyer
Dissertations - ALL
The PI3K pathway is a major cell signaling pathway that influences survival and longevity in eukaryotic cells. Abnormal signaling of this pathway has been implicated in a number of disorders, including Alzheimer's disease and cancer. The PI3K pathway utilizes the inositolphospholipid PI(3,4,5)P3 as a key secondary messenger in the transmission of signals from outside the cell to the nucleus. The SRC Homology 2 containing Inositol 5’-Phosphatase (SHIP) also plays a key role in the PI3K pathway, mediating hydrolysis of the inositol phospholipid PI(3,4,5)P3 to PI(3,4)P2. Early testing has shown modulation of SHIP activity through the use of small molecule modulators …
Partial Coalescence Of Cdse/Cds Core/Shell Nanocrystals,
2022
St. Mary's University
Partial Coalescence Of Cdse/Cds Core/Shell Nanocrystals, Jordyn Wray
Honors Program Theses and Research Projects
Quantum dots are semiconductor nanocrystals that are a few nanometers in size that have different optical and electrical properties depending on size and shape. Some applications that quantum dots are used for, include, lasers, quantum computing, and solar cells. The goal of the research was to fuse cadmium selenide, cadmium sulfide (CdSe/CdS) core shells into dimers to increase the communication between particles in these applications. The CdSe were synthesized to 3 nm cores. Various procedures were used for CdSe/CdS synthesis, but the best performing sample contained 5 nm particles in diameter and a promising size for fusion. A metal salt …
Investigating The Electrochemical Behavior Of Dihydropyrrolopyroles For Use As Anodically Coloring Electrochromes,
2022
Kennesaw State University
Investigating The Electrochemical Behavior Of Dihydropyrrolopyroles For Use As Anodically Coloring Electrochromes, Perry Skiouris, Ally Kisiel, Valentino Sorto, Julia Mauro, Graham Collier
Symposium of Student Scholars
Electrochromic materials have found widespread use in consumer electronics, energy saving windows, and military applications. They contain unique electronic properties allowing them to undergo a color change in a redox reaction. One classification of these molecules is known as anodically coloring electrochromes (ACEs). When in solution, these compounds are transmissive in the neutral (ground) state and absorb visible light upon oxidation, by the formation of a radical cation, thus making them colored. The focus of this study is the electronic transitions of this radical cation and how chemical modifications to the structures produce a variable color profile. To design prospective …
Designing And Synthesizing A Warhead-Fragment Inhibitory Ligand For Ivyp1 Through Fragment-Based Drug Discovery,
2022
Kennesaw State University
Designing And Synthesizing A Warhead-Fragment Inhibitory Ligand For Ivyp1 Through Fragment-Based Drug Discovery, Samuel Moore
Symposium of Student Scholars
Fragment-based drug discovery (FBDD) is a powerful tool for developing anticancer and antimicrobial agents. Within this, magnetic resonance spectroscopy (NMR) provides a comprehensive qualitative and quantitative approach to screening and validating weak and robust binders with targeted proteins, making NMR among the most attractive strategies in FBDD. Inhibitor of vertebrate lysozyme (Ivyp1) of P. aeruginosa serves as an excellent target because of its active cellular location and implications in clinical prognosis for cystic fibrosis and immunocompromised patients. This study uses current NMR and biophysical techniques to develop a covalent, fragment-linked warhead inhibitor for Ivyp1 through synthetic methods, warhead linking, and …
