Organic Chemistry Commons^™

The Effect Of Variation Of N-Substituents On Oxidopyridinium Ions In (4+3) Cycloadditions, Zahria Patrick, Madison Clark

Undergraduate Research Symposium

The aim of this research project is to expand the scope of 4 + 3 cycloadduct chemistry by varying functional groups attached to the prerequisite oxidopyridinium ion for each respective cycloadduct product. While N-substitution of the pyridinium precursor is known to proceed smoothly if alkylated by a lone methyl group, we evaluated the effect a larger alkyl group would have on the overall yield of the 4 + 3 cycloadduct product.

Isobutyl triflate, generated from the known reaction between isobutyl alcohol and triflic anhydride, was reacted with ethyl 5-hydroxy-nicotinate to generate the respective N-isobutyl oxidopyridinium ion in quantitative …

Etherification Of Propargylic Alcohol Using Ferrocenium Ions, Cody Amann, Sai Anvesh Bezawada, Eike B. Bauer

Undergraduate Research Symposium

Etherification of Propargylic Alcohol using Ferrocenium Ions

Cody Amann, Sai Anvesh Bezawada and Eike B. Bauer*

Department of Chemistry and Biochemistry, University of Missouri-St.Louis, MO 63121

Our research efforts are directed toward the improvement of iron-based catalyst systems. The Bauer research group recently found that the ferrocenium cation is a catalytically active in the etherification of propargylic alcohols. My research was to compare the effect of two different counteranions of the ferrocenium cation on the catalytic activity. Etherification test reactions were performed using 2-methyl-2-phenol-propargylic alcohol and n-butanol to afford the corresponding propargylic ether substitution products. The complexes used …

Adapting Chiral Gas Chromatography Into Existing Undergraduate Laboratories To Emphasize The Importance Of Stereochemistry, Ken Overway, Barnabas Otoo, Nicholas Griffin, Marshall Ritchie, Tyler Lynn, Kate Dear, Tyler Deutsch, Leigha Dillard

Chemistry Faculty Scholarship

Owing to the critical role of stereochemistry in biotechnology, medicine, and industry, it must be well represented in undergraduate lab curricula. To achieve these stereochemical laboratory requirements without sacrificing existing lab techniques, we modified two standard laboratory experiments to include chiral GC analysis as follows. (1) The extraction of carvone from spearmint leaves and caraway seeds via steam-distillation or other extraction methods is widely used in laboratories for analyzing the stereochemistry of the extracted products. The experiment was modified to include a GC method using a β-DEX 225 column. This allowed the students to compare the retention times of the …

Fluorescent Ph Indicators For Classroom Demonstration Of Buffer Action, Mark Muyskens, Mariana Dykstra, Yejin Chung

University Faculty Publications and Creative Works

We report an attractive update to the demonstration of acid−base buffer action that is appropriate for ease of use and getting attention in the classroom. The twist is based on new fluorophore information and the recent availability of UV flashlights serving as an ideal, portable excitation light source. The pH-dependent fluorescence comes from a choice among three natural sources, namely narra tree wood extract, kidneywood extract, and scopoletin, which is a purchasable coumarin, that all perform equally well. We provide practical details for performing the buffer demonstration at scales of 100 and 1000 mL and give background information for context

Research Trends And Impact Report On Aggregation-Induced Emission (Aie), 2001-2021, Elsevier Analytical Services

Public Reports

Since the concept of AIE was first proposed in China in 2001, it has gradually grown to a field of science that attracts dedicated researchers from around the world. Elsevier's data analytics team used AIE experts' interpretation of current theoretical, technological, and industrial development trends in the field for reference to collect AIE-related global scientific publications (from the Scopus database) to serve as a publication set in the field of AIE. This was undertaken to present, accurately and objectively, the development of AIE research over the past two decades and the latest scientific advancements in the field; to facilitate the …

Chemoselective Reduction Of Dicarboxylic Acids Via Iridium Catalyzed Hydrosilylation, Linda Lallawmsangi

Chemistry & Biochemistry Theses - Archive

Reduction of esters to aldehydes poses a challenge since the resulting aldehydes are often more reactive than the initial esters toward nucleophilic hydride-reducing agents. Although bulky, more controllable reducing agents such as lithium tri-tert-butoxyaluminum hydride or diisobutylaluminum hydride (DIBAL-H) have been developed, they are hazardous, sensitive to moisture and air, needing strict reaction conditions, and unsuitable with a wide range of functional groups. We present the design of an iridium-catalyzed chemoselective hydrosilylation method for dicarboxylic imides, followed by hydrolysis to eliminate the amide and yield aldehydes. This approach offers versatility in general reduction chemistry, holds promise for application …

Advanced Detection Of Sars-Cov-2 And Omicron Variants Via Mxene-Graphene Hybrid Biosensors Utilizing Nucleic Acid Probes, Jiaoli Li, Yuwei Zhang, Congjie Wei, Yanxiao Li, Zhekun Peng, Hsin Yin Chuang, Logan Pearce, Adrianus Boon, Yue-Wern Huang, Dong Hyun Kim, Risheng Wang, Chenglin Wu

Biological Sciences Faculty Research & Creative Works

Low-cost biosensors that can rapidly and widely detect viruses are critical for faster diagnosis and treatment decision-making, especially for infections. The commonly used field-effect transistor is sensitive to the biomarker's detection but struggles with precise detection, particularly of nontargets such as ions and proteins. To overcome this limitation, we developed a field-effect transistor biosensor design based on MXene-graphene materials to increase the accuracy and sensitivity of virus detection. Based on the hybridization process between two complementary DNA strands, single-stranded nucleic acids were immobilized on the sensing surface via 3-aminopropyltriethoxysilane and glutaraldehyde to capture the nucleic acids of the target virus. …

Phenanthrene Jamboree, Alexander D. Roth

Honors Theses

Using cyclopropanated and cyclobutanated phenanthrene precursors, our hero embarks on a mission to find as many reactive intermediates as possible. Fraught with danger, romance, and mangosteens, Anderson calls this work 'monstrous' and 'alarming.'

Studies Towards High Surface Area Porous Polymers Via Cross-Coupling Methodology, Anthony Lybrand

Wayne State University Theses

Porous polymers, known for their high internal surface area and robust chemical stability, are promising candidates for applications in gas storage, water purification, energy storage, and catalysis. The Yamamoto-type Ullmann reaction, known for yielding high porosity polymers, serves as a benchmark in this study. However, its limitations as a homocoupling reaction restricts the synthesis of ordered A-B type copolymers. This research addresses this challenge by investigating the use of cross-coupling reactions, particularly the Negishi reaction, to synthesize A-B type copolymers with reduced defectivity and enhanced surface area. The synthesis of fully-metalated intermediates and their subsequent polymerization are discussed in detail. …

Design, Synthesis, And Evaluation Of Class Iia Histone Deacetylase (Hdac) Inhibitors, Lauren Nicole Kotsull

Wayne State University Dissertations

Histone deacetylase (HDAC) proteins are linked to disease states, including cancer, and have become important targets for therapeutic development. Many inhibitors have been developed to target HDAC proteins, including FDA-approved inhibitors Vorinostat (SAHA), Belinostat, Romidepsin, and Panobinostat. These inhibitors non-specifically influence most of the 11 metal-dependent HDAC isoforms, which might contribute to the side effects that patients experience during treatment. The lack of selectivity also diminishes the use of HDAC inhibitors as biomedical research tools. To address these drawbacks, the development of selective inhibitors has been heavily studied. Yet, reported inhibitors are predominantly selective for class I HDAC isoforms (HDACs …

Dna Origami-Assisted Regioselective Organization Of Anisotropic Gold Nanotriangle Clusters, Wenyan Liu, Prashant Gupta, Yuwei Zhang, Krishna Thapa, Srikanth Singamaneni, Risheng Wang

Chemistry Faculty Research & Creative Works

The manipulation of anisotropic nanoparticles, such as gold nanorods and nano prisms, has attracted great attention in nanotechnology due to their sensitive geometry-dependent properties. However. traditional synthesis and assembly methods for these particles face challenges in size uniformity and higher-order structuring. To address these limitations, this study presents a strategy using DNA origami triangles, not just as templates, but as encapsulating agents for gold nanotriangles (AuNTs). This method enables the construction of diverse nanoparticle clusters with precisely controlled distance and orientation. The formed clusters exhibit unique optical characteristics, demonstrated by UV-visible spectroscopy and supported by finite-difference time domain (FDTD) simulations. …

Room Temperature Decarboxylative Amination Reactions Of Carboxylic Acids, Rabina Basnet

Graduate Theses, Dissertations, and Problem Reports (ETD)

Anilines are important structural motifs present in numerous natural products and pharmaceutically relevant compounds. Among the various synthetic strategies that have been developed, transition-metal-catalyzed cross-coupling reactions represent one of the most commonly employed methods for the formation of anilines. However, these approaches generally require pre-functionalized aryl coupling partners, and the utilization of more readily available, and structurally diverse coupling partners, such as carboxylic acids, would be desirable. Decarboxylative coupling reactions have garnered significant attention as an alternative approach to form new C-N bonds, and substantial progress has been made in this area. Nevertheless, these methods remain limited, with a predominant …

Nickel-Catalyzed Regioselective Three-Component Coupling Of Phenyl Vinyl Sulfones With Alkynes, Stephen M. Long

Graduate Theses, Dissertations, and Problem Reports (ETD)

Benzene rings are some of the most prevalent motifs found in small molecule drugs with only a few dominant substitution patterns, 1-, 1,2-, 1,4-, and 1,2,4-. Nucleophilic aromatic substitution and electrophilic aromatic substitution are traditional methods for the synthesis of substituted benzenes and are robust and commonly used by chemical manufacturers, which explains in part the observed distribution of substitution patterns. Current methods to access substituted benzenes comprise of transition-metal-catalyzed C-H activation, transition-metal-catalyzed cross-coupling, and aryne chemistry. In general, the present methods require directing/leaving groups in specific positions to proceed, which inherently puts a limitation on substrate scope. Transition-metal-catalyzed [2+2+2] …

Illuminating Function And Enabling Inhibition At The Protein-Membrane Interface Of Glutathione Peroxidase 4., Courtney L. Labrecque

Theses and Dissertations

Membrane proteins act as gateways to cells and are responsible not only for signaling, lipid transport, and cellular homeostasis, but they are also integral in disease pathologies. One class of membrane proteins, peripheral membrane proteins (PMPs), reside in aqueous compartments of the cell until they are recruited to the membrane to perform their function. Glutathione peroxidase 4 (GPx4) is a PMP enzyme responsible for engaging the membrane and reducing lipid hydroperoxides, thereby preventing cellular death via ferroptosis. Due to its central function surrounding ferroptosis, GPx4 is an interesting drug target that has recently gained interest for inflammatory diseases as well …

Chemical Synthesis And Biological Application Of Sensitive Rna, Alexander T. Apostle

Dissertations, Master's Theses and Master's Reports

In the field of epigenetics - the dynamic collection of chemical modifications that overlay DNA/RNA - there is increasing interest in the potential for therapeutic and research-based utilization of the epitranscriptomics: those epigenetic modifications specific to RNA. Epitranscriptomics can give us a new approach to understanding and treating RNA viruses, like SARS-CoV-2. Given viruses are often found modified by human epitranscriptomic machinery, understanding how these modifications can modulate virulence is of high interest. We have shown that the N1-methyladensoine modification causes RNA synthesis termination in the SARS-CoV-2 replication complex, and thus may explain the differences in symptoms observed in individuals. …

Green Oxidation Of Aromatic Hydrazide Derivatives Using An Oxoammonium Salt, Nidheesh Phadnis, Jessica A. Molen, Shannon M. Stephens, Shayne M. Weierbach, Kyle M. Lambert, John A. Milligan

Chemistry & Biochemistry Faculty Publications

Aromatic diazenes are often prepared by oxidation of the corresponding hydrazides using stoichiometric quantities of nonrecyclable oxidants. We developed a convenient alternative protocol for the oxidation of aromatic hydrazides using Bobbitt's salt (1), a metal-free, recyclable, and commercially available oxoammonium reagent. A variety of aryl hydrazides were oxidized within 75 min at room temperature using the developed protocol. Computational insight suggests that this oxidation occurs by a polar hydride transfer mechanism.

Unraveling Sources Of Cyanate In The Marine Environment: Insights From Cyanate Distributions And Production During The Photochemical Degradation Of Dissolved Organic Matter, Rui Wang, Jihua Liu, Yongle Xu, Li Liu, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

Cyanate is a nitrogen and energy source for diverse marine microorganisms, playing important roles in the nitrogen cycle. Despite the extensive research on cyanate utilization, the sources of this nitrogen compound remain largely enigmatic. To unravel the sources of cyanate, distributions and production of cyanate during photochemical degradation of natural dissolved organic matter (DOM) were investigated across various environments, including freshwater, estuarine, coastal areas in Florida, and the continental and slope regions of the North American mid-Atlantic Ocean (NATL). Cyanate production was also examined during the photochemical degradation of exudates from a typical strain of Synechococcus, an important phytoplankton …

Toxicity Of Crude Oil-Derived Polar Unresolved Complex Mixtures To Pacific Herring Embryos: Insights Beyond Polycyclic Aromatic Hydrocarbons, Maxwell L. Harsha, Yanila Salas-Ortiz, Alysha D. Cypher, Ed Osborn, Eduardo Turcios Valle, Jacob L. Gregg, Paul K. Hershberger, Yuri Kurerov, Sarah King, Aleksandar I. Goranov, Patrick G. Hatcher, Anastasia Konefal, T. Erin Cox, Justin B. Greer, James P. Meador, Matthew A. Tarr, Patrick L. Tomco, David C. Podgorski

Chemistry & Biochemistry Faculty Publications

Crude oil toxicity to early life stage fish is commonly attributed to polycyclic aromatic hydrocarbons (PAHs). However, it remains unclear how the polar unresolved complex mixture (UCM), which constitutes the bulk of the water-soluble fraction of crude oil, contributes to crude oil toxicity. Additionally, the role of photomodification-induced toxicity in relation to the polar UCM is not well understood. This study addresses these knowledge gaps by assessing the toxicity of two laboratory generated polar UCMs from Cook Inlet crude oil, representing the readily water-soluble fraction of crude oil and photoproduced hydrocarbon oxidation products (HOPs), to Pacific herring (Clupea pallasii …

Evaluating The Influence Of Trypanosomiasis On Murine Model Using Corchorus Olitorius Leaf Extract As A Trypanocidal Agent, Fatima M. Madaki, Adamu Y. Kabiru, Ogunrombi D. Clinton, Sakariyau A. Waheed, Yunusa O. Ibrahim

Chemistry & Biochemistry Faculty Publications

Trypanosomiasis, a parasitic disease caused by trypanosomes, which are flagellate protozoa transmitted through the bite of the tsetse fly, manifests with symptoms including substantial weight loss, anemia, fever, edema, adenitis, dermatitis, and nervous disorders. This research investigated the impact of trypanosomiasis on a murine model while utilizing Corchorus olitorius leaf extract as a potential trypanocidal agent. An acute toxicity analysis was conducted following Lorke's method, and the antitrypanosomal efficacy was assessed in rats at doses of 100, 200, and 400 mg/kg over three weeks, monitoring changes in parasitemia count, body weight, and hematological parameters. Additionally, lipid profile, electrolyte concentration, and …

Advancements In The Synthesis Of Polyoxygenated Oxepanes And Thiepanes For Applications To Natural Products, Aditya R. Pote, Shayne M. Weierbach, Mark W. Peczuh, Kyle M. Lambert

Chemistry & Biochemistry Faculty Publications

Oxepanes are central motifs and tenants of many biologically important molecules, and their synthetic construction often presents a challenge to chemists due to consequential entropic and enthalpic barriers that have limited the synthetic toolbox to access these seven-membered oxacycles. This review covers the breadth of synthetic methods to afford the oxepane/thiepane moiety, with a focus on polyoxygenated oxepanes and includes radical cyclizations, Lewis acid-mediated cyclizations, ring closing-metathesis, Nicholas-Ferrier rearrangement, homologations, and ring-expansion strategies. Implementation of these tactics towards sugar-based and non-sugar based (de novo) approaches is presented alongside their extensive application to the total synthesis of several complex polyoxygenated oxepane-containing …