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Full-Text Articles in Chemistry

Development And Applications Of Novel And Practical Fluorination Reagents., Yuhao Yang Aug 2023

Development And Applications Of Novel And Practical Fluorination Reagents., Yuhao Yang

Electronic Theses and Dissertations

The fluorine (F) atom has distinctive properties such as the highest electronegativity, small size, low polarizability, and strong C–F bond strength. Not surprisingly, fluorinated organic compounds have garnered significant attention in the pharmaceutical, agrochemical, and material fields. Since organofluorides are very rare in nature, we need fluorination reagents to help us transfer fluorine into the organic molecules. In past decades, a vast number of fluorination reagents have been developed and many of them are commercially available now. However, there is still much room for the improvement of these reagents. Our target is to develop novel and practical fluorination reagents to …


New Methodologies For Sustainable Organic Synthesis In Water., Sudripet Sharma Aug 2023

New Methodologies For Sustainable Organic Synthesis In Water., Sudripet Sharma

Electronic Theses and Dissertations

Water is stable, benign, and green solvent. Its usage as a solvent in organic synthesis is significantly enhanced by micellar catalysis. However, replacing water as a reaction medium in organic synthesis is not sufficient to meet the sustainability challenges—excessive organic solvents are still required for product isolation and purification. Notably, solvents used in syntheses contribute to more than 80% of waste generation. In addition to solvents, the use of palladium in large amounts is also a problem for the future as it is a precious, low-abundance metal, and its supply is dwindling. Therefore, this dissertation highlights the various sustainable protocols …


Alpha, Beta-Unsaturated Aldehydes: The Underrepresented Markers Of Disease., Saurin Sutaria Dec 2022

Alpha, Beta-Unsaturated Aldehydes: The Underrepresented Markers Of Disease., Saurin Sutaria

Electronic Theses and Dissertations

The peroxidation of unsaturated fatty acids is a widely recognized metabolic process that creates a complex mixture of volatile organic compounds including aldehydes. Elevated levels of reactive oxygen species in cancer cells promote random lipid peroxidation, which leads to an increase in a variety of aldehydes. Many of these volatile aldehydes are exhaled and are of interest as potential markers of disease. Chapter 1 presents a review of reported aldehydes in the exhaled breath of lung cancer patients. alpha,beta-Unsaturated aldehydes, detected primarily when derivatized during exhaled breath preconcentration, are underreported in the reviewed articles. Chapter 1 concludes with our hypothesis …


Alkylthiocarbamate Metal Complexes With Antiproliferation Activity., Kritika Bajaj Aug 2022

Alkylthiocarbamate Metal Complexes With Antiproliferation Activity., Kritika Bajaj

Electronic Theses and Dissertations

Bis(thiosemicarbazones) (BTSCs) and their metal complexes have been extensively studied for various applications including catalysis for hydrogen evolution reactions, treatment of neurodegenerative diseases, hypoxia imaging, and a wide range of pharmacological purposes including antitumor, antiviral, antibacterial, and antifungal agents. The paramount property that makes BTSC metal complexes interesting for their use in these applications is the reduction potential of the coordinated metal, which can be selectively tuned by varying the substituents present on the ligand framework. Although the BTSCs have shown a great deal of success as potential cancer therapeutic agents, they lack selectivity towards cancer cells. For this matter, …


Surface-Functionalized Chemiresistive Films That Exploit H-Bonding, Cation-Pi, And Metal-Halide Interactions., Prasadanie Karunarathna Adhihetty May 2022

Surface-Functionalized Chemiresistive Films That Exploit H-Bonding, Cation-Pi, And Metal-Halide Interactions., Prasadanie Karunarathna Adhihetty

Electronic Theses and Dissertations

The development of gas sensors for detection of volatile organic compounds (VOCs) has been of interest in the sensing field for decades. To date, the use of metal nanoparticle-based chemiresistors for trace VOC detection, particularly gold nanoparticle-based sensors, is of great interest due to their high chemical stability, ease of synthesis, unique optical properties, large surface to volume ratio, and high level of conductivity. Much effort has been devoted towards gold monolayer protected clusters (Au MPCs) as chemiresistors to detect harmful VOCs. The present thesis documents the results of our efforts to exploit the advantages of functionalized Au MPCs chemiresistors …


Development And Novel Applications Of Halogenating Agents., Sagar Ravso Mudshinge May 2022

Development And Novel Applications Of Halogenating Agents., Sagar Ravso Mudshinge

Electronic Theses and Dissertations

Organic halides are extensively utilized as synthetic intermediates in areas such as pharmaceuticals, agrochemicals, and material polymers. While many halogenating agents have been developed, they continue to have low efficiency or selectivity, are difficult to handle, and often have limited substrate scope. To address this issue, our laboratory has developed novel halogenating agents with improved stability and efficiency. In these studies, we demonstrated a novel application of halogenating reagent, HCl·DMPU, in the nitrile synthesis. We developed a novel method for C−SCF3/SeCF3 cross-coupling reactions using gold redox catalysis. We developed a novel trifluoromethylating agent in a cost-effective and …


Sustainable Nanocatalysis In Water For C–C And C–N Cross-Couplings., Tharique Ahammed Ansari Nalakath May 2022

Sustainable Nanocatalysis In Water For C–C And C–N Cross-Couplings., Tharique Ahammed Ansari Nalakath

Electronic Theses and Dissertations

The development and application of various micelle-enabled nanopalladium-catalyzed organic transformations are discussed in this dissertation. These methodologies primarily harness the “micellar effect” imparted by the custom-designed amphiphile PS-750-M. Modern spectroscopic and imaging techniques were employed to systematically study the metal-micelle interactions and answer the fundamental questions regarding the operational nature of micellar catalysis. Chapter 1 reviews the history and evolution of organic synthesis, providing a critical outlook regarding the alarming inefficiency of contemporary synthetic practices indicating an inevitable transition to more sustainable synthetic techniques. In this context, the development of micellar catalysis is discussed, emphasizing its basic principles, applications, and …


Micellar Nanocatalysis For Efficient Reactions., Uyen T Duong Aug 2021

Micellar Nanocatalysis For Efficient Reactions., Uyen T Duong

Electronic Theses and Dissertations

Water is considered a green, sustainable, and inexpensive solvent for organic synthesis. However, performing organic reactions in water is especially challenging due to the inherent insolubility of substrates and catalysts. Inspired from Nature, where chemistry happens in water, micellar catalysis has recently gained much attention, especially for applications in pharmaceutical industry. Aqueous micelles are generally formed by amphiphile`s self-aggregation, a particular class of molecules possessing both hydrophobic and hydrophilic components. The aqueous micelle contains a hydrophobic cavity, which allows the lipophilic substrates and catalyst to go inside micelles, allowing their much higher localized concentration that enhances the reaction rates and …


Micelles And Lipid Nanoparticles: Catalysis And Biomedical Application., Faisal Ibrahim Aug 2021

Micelles And Lipid Nanoparticles: Catalysis And Biomedical Application., Faisal Ibrahim

Electronic Theses and Dissertations

RNA-based therapeutics is a rapidly expanding field due to its enormous potential for treatment of diseases through knockdown of genes or expression of therapeutic proteins. However, due to the overall negative-charge of an RNA molecule, RNA-based therapeutics must rely on delivery systems to overcome the various biological barriers for ultimate release of an RNA payload into the cytosol. Over the past three decades, the development of lipid-based RNA delivery systems, especially lipid nanoparticles (LNPs), have been comprehensively studied due to their unique properties. LNPs represent the most widely used delivery systems for RNA-based therapeutics, as evidenced by the clinical approvals …


Recent Studies On The Synthesis Of Medicinal Molecules., Paige Monsen Aug 2021

Recent Studies On The Synthesis Of Medicinal Molecules., Paige Monsen

Electronic Theses and Dissertations

Medicinal chemistry interfaces synthetic organic chemistry, natural product chemistry and chemical biology, with a goal of yielding therapeutic agents. Natural products or compounds derived from natural sources such as plants, animals, and microorganisms, are often biologically active and render that compound a likely drug lead. For thousands of years humankind has utilized natural products for medicinal purposes and consequently scientists take advantage of both these compounds’ core structural characteristics and their modes of actions on selected targets as inspiration to develop therapeutics. Because the total synthesis of such complex molecules can be cumbersome and expensive, semi-synthetic methods on isolated natural …


(Pseudo)Phase Tuning In The Service Of Synthesis: Technologies For Sustainable Catalysis., Justin Douglas Smith Aug 2020

(Pseudo)Phase Tuning In The Service Of Synthesis: Technologies For Sustainable Catalysis., Justin Douglas Smith

Electronic Theses and Dissertations

Strategies for manipulation of chemical phases were explored with emphasis on synthetic chemistry applications. Some strategies are fairly divergent from their origin, but all ultimately began from investigations of micellar media. Accordingly, Chapter 1 reviews the historical development of micellar catalytic processes. Chapters 2 and 3 detail development of synthetic methods in micellar solutions of designer surfactant PS-750-M. PS-750-M was designed to create benign micellar solutions which effectively mimic toxic organic solvents; it contains a proline-based linker between its hydrophobic and hydrophilic regions which imparts increased polarity to the micellar core. Chapter 2 details an interfacial nucleophilic substitution of perfluoroarenes …


Functional Nanomaterials By Combining Aminooxy Chemistry And Iodine Activation At Momolayer Protected Clusters., Tirtha Raj Sibakoti May 2020

Functional Nanomaterials By Combining Aminooxy Chemistry And Iodine Activation At Momolayer Protected Clusters., Tirtha Raj Sibakoti

Electronic Theses and Dissertations

Aminooxy (-ONH2) groups are most commonly known for their chemoselective reaction with carbonyl compounds (aldehydes/ketones) under mild reaction conditions. Aminooxy-based click chemistry is a versatile means of ligation as evidenced by broad application in material science, biology, biochemistry, analytical chemistry, and nanoscience. Our work exploits the facile reaction of aminooxy groups presented on the surface of gold (Au) or palladium (Pd) monolayer protected clusters (MPCs) with various aldehydes via oximation reactions, which form the robust oxime ether adducts. The functionalization of hexanethiolate-stabilized Au MPCs with a newly developed trifunctional amine-containing aminooxy alkanethiol ligand by thiol place-exchange affords aminooxylated …


Synthetic Methods And Biological Applications Of Nitrogen Heterocycles To Compounds Of Biological Interest., Jarrid Ronnebaum May 2019

Synthetic Methods And Biological Applications Of Nitrogen Heterocycles To Compounds Of Biological Interest., Jarrid Ronnebaum

Electronic Theses and Dissertations

Thalidomide analogues were synthesized utilizing optimized click conditions from 3-azidoglutarimide and an array of arylacetylenes or N-ethynyl/N-propargyl phthalimide derivatives. The intermediate, 3-azidoglutarimde, was pivotal and yielded a new and scalable synthesis. The reaction conditions utilized a copper sulfate/sodium ascorbate system in aqueous tetrahydrofuran to propagate the dipolar cycloaddition reactions between the azidoglutarimide and the alkynyl coupling partners. The first explored substrates were substituted arylalkynes to optimize the click reaction. Arylalkynes selected were to exhibit similar electron deficient rings to mimic phthalimide. Along with the synthesis of click thalidomide analogues, click analogue of the antiangiogenic and more potent …


Facile And Efficient Synthesis Of Thiosemicarbazone Derivatives With Functionalized Pendant Amines., Anna E Davis Mar 2019

Facile And Efficient Synthesis Of Thiosemicarbazone Derivatives With Functionalized Pendant Amines., Anna E Davis

College of Arts & Sciences Senior Honors Theses

Bis-thiosemicarbazones are an important class of ligands for the synthesis of transition metal complexes with applications in medicine and electrochemistry.1,2 Among the most studied of these complexation ligands is diacetyl-2,3-bis(N4-methyl-3-thiosemicarbazone) (denoted as ATSM, 1, Figure 1).2,3 Derivatives of 1 with various amines in place of the methylamine of ATSM have previously been reported, including diacetyl (N4-methylthiosemicarbazone-N4′-dimethylthio-semicarbazone) (denoted as ATSM/DM, 2).4 In this work, we pursue the development of a library of ATSM derivatives with a variety of functionalized pendant amines with a range of electronic and steric …


Long-Range Electrostatic Interactions In Gold Catalysis And Fluorinating Reagent Development., Zhichao Lu May 2018

Long-Range Electrostatic Interactions In Gold Catalysis And Fluorinating Reagent Development., Zhichao Lu

Electronic Theses and Dissertations

Our research focus is on applying two long range electrostatic interactions--coulombic interaction between ion pairs and hydrogen bonding—to two tasks: exploring counterion effects in gold catalysis and utilizing hydrogen bonding for fluorinating reagent development. Cationic gold catalysis is considered one of the most important breakthroughs in organic synthesis over the past two decades. A wealth of empirical information on counterion effects is now available regarding homogeneous gold catalysis. However, the rational understanding of the counterion effect on reactivity is still elusive. We proposed a widely applicable model to rationalize the kinetic effect in gold catalyzed reaction. We first solved the …


Development Of Recyclable Gold Nanoparticles For Routine Benchtop Catalysis In Organic Transformations., Shengzong Liang May 2017

Development Of Recyclable Gold Nanoparticles For Routine Benchtop Catalysis In Organic Transformations., Shengzong Liang

Electronic Theses and Dissertations

Homogeneous gold catalysis is a popular research area due to its high efficiency. Various gold catalysts have been utilized in organic synthesis and their reaction mechanisms are also well understood. However, most gold catalysis suffers from high catalyst loading or catalyst decay problems. In addition, homogeneous gold catalysts are not recyclable. These disadvantages have limited their application in large-scale synthesis and also caused a serious waste of this precious metal. A solution for these problems is to use a recyclable heterogeneous gold catalyst. So in this study, with the aim of making gold chemistry greener we successfully used heterogeneous gold …


Chemoselective Reactions And Their Applications In Metabolite Isolation And Analysis., Sadakatali Shokatali Gori May 2016

Chemoselective Reactions And Their Applications In Metabolite Isolation And Analysis., Sadakatali Shokatali Gori

Electronic Theses and Dissertations

Chemoselectivity is the preferential reaction of a reagent with a select functional group among other plausible reactions. This dissertation describes chemoselective reagents and methods explored to develop more accurate, efficient and high-throughput means to quantify metabolites containing either thiol, carboxylic acid or 1,2-diol moieties directly from biological mixtures. Chapter 1 discusses how dysregulation of thiol- or carboxylic acid-containing metabolites is either the cause or effect of cellular dysfunction. Quantifying such metabolites is important in discovery of pathways to understand etiology of diseases. Chapter 1 also discusses the need for sustainable syntheses using renewable resources and describes the traditional methods for …


A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006 Jan 1945

A Study Of Factors Influencing The Hydrolysis Of Corn Amylopectin By Barley Malt Enzymes., Thelma Munsey Back 1918-2006

Electronic Theses and Dissertations

No abstract provided.