Organic Chemistry Commons^™

The Potential Importance Of Microenvironment On Polymer Bound Chemical Reagents, Nathan Joseph Halsteter

Theses and Dissertations

In this thesis will provide a brief history of polymer bound reagents, their uses, and advancements. The importance of polymer microenvironments will be explored using a model kinetic resolution reaction utilizing polymer bound reagents to observe how changes in a polymer’s microenvironment effects the yield and selectivity of a reaction. It was found that there are copious factors that affect polymer bound reagents, and no direct conclusion could be drawn from the study.

Structure-Activity Relationships Of Isothiourea And Silicon Phthalocyanine Catalysts, Christian J. Harrison

Theses and Dissertations

Efficient organic synthesis often relies on improving catalyst designs and investigating reaction mechanisms to accomplish feats such as high stereoselectivity, low catalyst loadings, and performing sustainable chemistry. Within the field of organocatalysis, intermolecular interactions between a catalyst and a substrate are a large contributing factor to the control of a reaction, including rate and selectivity. Investigating mechanisms can provide information on the type of intermolecular interactions occurring in the reaction, aiding future reaction and catalyst development. This dissertation will explore two recent projects and how probing intermolecular interactions through simple modifications provides information useful for new catalyst designs and properties. …

Lighting Up The Cell: Developing A Luminescent Lanthanide Probe For Detecting Rnas, Jonathan Savell

Honors Projects

An anion detecting luminescent probe, Tb:DO2A-Cs124, was repurposed for use in RNA imaging. Potential RNA aptamers were identified for the molecule using Capture-SELEX and MinION sequencing. Fluorimetry data revealed these aptamers did not allow for the probe to luminesce in the presence of target RNAs due to adenosine monophosphate’s ability to quench the emission signal.

Complementary Design Of Optical And Photochemical Systems, Joshua Plank

Chemistry Theses and Dissertations

The ability to manipulate chemical systems has been prized through history as the bridge between the macroscopic and microscopic worlds. As an example, the camera obscura has arguably existed since the earliest days of humanity; however, it was the discovery of early silver halide chemistry that lead to the ability to fix these images into the earliest photographs. In modern photolithography employed in electronics manufacturing, the primary resolution limits arise not from the chemistry of the molecules involved, but from the limits of the systems used to project light. Thus, as much as photochemistry advances, optical imaging and projection techniques …

Asymmetric, Carboxy And Ester Functionalized Fluorophthalocyanines: Synthesis, Adsorption, And Reactivity, Sean J. Scally

Seton Hall University Dissertations and Theses (ETDs)

Strong electron-deficient compounds, fluorinated metal phthalocyanines (F_xPcM), exhibit enhanced photosensitizing properties, making them optimal candidates for photocatalytic studies. Perfluoroalkyl-substituted phthalocyanines are notably thermally robust materials that are chemically inert and resistant to electrophilic, nucleophilic, and radical, including reactive oxygen species (ROS) attacks. These properties can be attributed to their ‘Teflon-like’ inert organic shield that surrounds a reactive metal center, as well as their complete (x = 16, 40, 64), or almost complete (x = 48) lack of C-H bonds. Third-generation, functionalized, asymmetric phthalocyanines are of interest due to their ability to bind to oxidic supports via a carboxyl …

Bio-Based Composites With Enhanced Mechanical Strength And Flame Retardancy, Riya Patel

Electronic Theses & Dissertations

Composites are versatile and useful in many fields, including aerospace, automotive, construction, and healthcare, due to their high mechanical strength. It is common practice to synthesize these materials using petroleum-based chemicals. Nonetheless, in the twenty-first century, scientists are more interested in using renewable resources to create composites. The greatest substitute for petroleum-based chemicals is vegetable oil. It has unsaturated double bonds that are modifiable chemically. In the present study, bio-polyol was synthesized using castor oil, an inedible vegetable oil. A ring-opening process was used to modify it and produce castor oil-based polyol. The synthesized castor oil-based polyol was characterized by …

Trade-Off Between Limonene & Geraniol-Based Reprocessable And Non-Reprocessable Epoxy Thermosets: Role Of Aliphatic Diamines In Polymer Networks Design, Priyankkumar Kanubhai Patel

Electronic Theses & Dissertations

The growing demand for sustainable materials, driven by environmental concerns and the rapid depletion of fossil fuels, has garnered significant attention in the fabrication of bio-based epoxy thermosets as renewable alternatives to petroleum-derived thermosetting polymers. The present study focuses on the synthesis and characterization of epoxy prepolymer resins derived from limonene and geraniol via a two-step process, followed by the fabrication of thermally cross-linked flexible epoxy thermoset films using various traditional aliphatic diamine curing agents, namely 1,2-ethylenediamine (EDA), 1,4-butylenediamine (BDA), and 1,6-hexamethylenediamine (HDA). Additionally, the incorporation of cystamine, a disulfide-containing diamine, enabled the formation of a covalent adaptable network through …

Enabling New Synthetic Platforms For Aryne Synthesis With Aryl Thianthrenium Reagents, Riley Augustus Roberts

Dissertations and Theses

The enormous importance of aromatic rings in organic molecules cannot be understated. Aromatic rings are present in the majority of pharmaceuticals, agrochemicals, and consumer products. The way in which these rings are arranged and substituted results in a molecule’s unique properties. Because of this, the current limitations of the chemical methods used to synthesize these molecules results in limited structural diversity and thus missed opportunities for the development of value-added products. To this end, this work demonstrates novel methods of aryne synthesis, aryl thianthrenium synthesis and a unique approach to structural scaffold hopping. The approaches presented herein allow for rapid …

Effects Of Structure Of Mepegn Polymers On Hydroxide Conductivity In Anhydrous Anionic Exchange Membranes, Athan M. Gregory

Honors Theses

Anhydrous hydroxide ion (OH-) conducting polymer electrolytes composed of a 1-methyl-pyrrolidinium (1mp) head group linked to various MePEGn (n = 3, 7, 12) backbones were prepared. We have examined the structure of these anion exchange membranes to observe how the structure of the electrolyte affects the observed ionic conductivity. The structural parameters investigated were polymer length, viscosity, fractional free volume (FFV), and volume fraction of PEG (Vf,PEG), and each polymer varied in these properties. Through a comparison of the conductivity and structural parameters in the MePEGn-based anion electrolytes, we have shown that each of these structural properties weakly affects the …

Bottom-Up Mechanochemical Synthesis Of Nanographene, Sarah Kerr

Honors Theses

This research explores the application of mechanochemistry in the bottom-up synthesis of nanographene, specifically focusing on the mechanochemical Diels-Alder (DA) reaction. The study investigates the effect of different reaction conditions and dienophiles on the mechanochemical DA reaction, aiming to optimize reaction efficiency and yield using a ball mill. The initial trials with a sterically hindered dienophile (2) and an electron-deficient diene experienced repeated failure, while reactions using dienophile (B), a terminal alkyne showed more promising results. Various variables were examined, including reaction time, jar size, ball size, ball number, shaking frequency, liquid-assisted grinding (LAG), heating, and diene to dienophile ratio, …

Typical Electron-Withdrawing Groups Are Ortho, Meta-Directors Rather Than Meta-Directors In Electrophilic Aromatic Substitution, Paul R. Rablen

Chemistry & Biochemistry Faculty Works

Electron-withdrawing groups are traditionally considered meta-directing in aromatic substitution reactions. However, when the pre-existing substituent is a π-acceptor, both experiment and calculation indicate that substantial amounts of ortho as well as meta substitution occur, with very little para reactivity. A simple perturbative MO argument rationalizes this finding. It is therefore suggested that these substituents are best understood as ortho, meta-directors, with a preference for meta, just as electron-donating groups are considered ortho, para-directors, with a preference for para.

Development Of Mixed O/S-Donor Imidazole Thione Ligands For Trivalent Lanthanide/Actinide Separations, Rhianna Wolsleger

All Dissertations

Separation of lanthanides and actinides is difficult due to their very similar size and charge. Increasing selectivity for actinides over lanthanides is possible by incorporating a softer, more polarizable donor atom into a chelating ligand, since the softer donor atom is capable of greater orbital overlap with the 5f orbitals of the actinides vs the 4f orbitals of the lanthanides. Sulfur-containing imidazole thione chelating ligands have not been investigated for this purpose but possess a resonance structure that puts significant negative charge on the sulfur, enabling it to form strong metal-sulfur bonds compared to other sulfur-containing ligands such as thioethers …

Synthetic Efforts Towards An Analog Of Ly426965, Macy Sproles

Honors Theses

The 5-hydroxytryptamine_1A (5-HT_1A) receptor is a key target in the treatment of various neuropsychiatric conditions, and the development of selective antagonists offers promising therapeutic potential.²⁴ This study aimed to develop a synthetic analog of LY426965, a selective 5-HT_1A receptor antagonist. The synthetic route was initiated from dimethyl-2-phenylmalonate, employing pig liver esterase (PLE) as an enantioselective biocatalyst to achieve regioselective hydrolysis of one ester moiety in the malonic diester intermediate.¹⁷ Through a series of stereochemically controlled transformations, a new intermediate was successfully synthesized. Although the target molecule was not obtained, a new compound was synthesized …

Synthesis, Characterization, And Redox Properties Of Select 1,4-Diazocine-6,11-Diones Towards An Electrochromic Dye-Set, Jeffrey Scott Richards

Open Access Theses & Dissertations

The daily consumption of personalized digital visual information depends on the current purview of electronic-based displays. Present manufacturers utilize modern technologies, such as LCD, OLED, QLED, and electronic ink, or "E Ink," in their devices to display text, pictures, and other forms of media to individual users. However, as modern society continues to rely on the use of digital displays, the demand for low-power alternatives will continue to rise as their application in varying scenarios is realized. Currently, "E Ink" technology continues to grow as the dominant solution in the e-readers and digital signage marketplace, and can even be seen …

A Study Of Ultrafast, Intense-Field Photodynamics In Carbon Dioxide, Carbon Disulfide, And Select Substituted Benzenes, Joshua Edwin Beck

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

The study of the photodynamics of molecules in ultrashort pulses of intense radiation continues to be of interest. Electric field strengths in such pulses can approach or exceed the typical electric field strengths binding the electrons to the nuclear framework (ke/a²₀ ≈ 5 × 10⁹ V/cm). The resulting excitation, ionization, and dissociation of molecular targets is of interest in many areas including attosecond science, femtochemistry, atmospheric science, high harmonic generation, and many other fields.

This dissertation investigates the photoionization and photofragmentation behavior of carbon dioxide, carbon disulfide, and the substituted benzenes nitrobenzene, aniline, as …

Synthesis Of Surface Bound Ligands Through Click Chemistry For A Tethered Catalyst System Towards The Reduction Of Carbon Dioxide, Emma J. Goehner

Departmental Honors & Graduate Capstone Projects

The electrochemical reduction of carbon dioxide (CO₂) offers a promising strategy for reducing excess atmospheric CO₂ by converting it into valuable chemical products. This process can be catalyzed by transition metal complexes, particularly those with extended aromatic ligands such as terpyridines which coordinate with metals in a tridentate fashion. When tethered to an electrode, the terpyridine-metal catalyst complex allows for stable binding and reusability without the need for chemical separation to recover the catalyst. Self-assembled monolayers (SAMs) of (3-bromopropyl) phosphonic acid were formed on copper surfaces, enabling attachment of terpyridine ligands through a click reaction between a …

Understanding The Through-Space Intermolecular Interactions Of Isothiourea Catalysts In Acylation/Silylation Reactions Of Secondary Alcohols, Ziyuan Gong

Theses and Dissertations

Through space interactions, including cation-π interaction, lone pair-πinteraction, steric hinderance etc. play a central role in organocatalytic reaction. They can control the reactivity or the selectivity of an organic reaction. Previous work in our group has already shown that the chiral isothiourea compounds can catalyze the acylation as well as silylation reaction of secondary alcohol with the possible cation-πinteraction between the catalyst and substrate. However, there is lack of study to understand how the delocalization of the positive charge would affect the reaction rate and whether some unexpected inter- or intramolecular interaction could help stabilize …

Trenching And Compost Sustain Grain Yield Increases Over Nine Years On Deep Sands But At A Cost, David J.M. Hall, Tom J. Edwards

Grain and Other Field Crops Research Articles

Context. Crops grown on deep sands on the south coast of WA are limited by soil physical and chemical properties including compaction and poor nutrition. Aims. Crops grown on deep sands on the south coast of Western Australia are limited by soil physical and chemical properties including compaction and poor nutrition. Our aim was to determine what effects deep-placed organic amendments have on soil properties and crop production in a deep sand and whether such amendments are profitable. Methods. A long-term field trial was conducted over nine years (2015–2023) to investigate soil amendments including lime (0 and …

Synthesis Of Novel Five-Membered Heterocycles As Bioactive Agents, Subrata Roy

Student Theses and Dissertations

This dissertation outlines the synthesis of various types of heterocyclic small molecules across three chapters. The first chapter discusses the efficient synthesis of seventy-one fluorinated pyrazole molecules and thirty-five 3,4-dihydroxy and 4-hydroxy phenyl-substituted thiazole molecules. These molecules were designed and synthesized for their potential antibacterial properties. The second chapter discusses the synthesis of fused thiazole molecules with enone-based steroidal natural products. This chapter reports on sixty-five novel fused thiazole molecules distributed across three libraries featuring different steroidal natural products: ethisterone, bisnoralcohol, and diosgenin. These molecules were designed and synthesized as potential anticancer agents. The third chapter comprises the development of …

Rewiring An Enzyme: K135f Mutation In Malate Dehydrogenase, Lauren Ratz, Kaci Schmoll

Undergraduate Research Symposium 2025

Malate Dehydrogenase (MDH) is an enzyme that catalyzes the reaction of malate to oxaloacetate by reducing the cofactor NAD+ to NADH in the citric acid cycle, playing a crucial role in cellular metabolism. Alterations in the MDH structure have been linked to metabolic diseases and cancers, though its overall structure remains poorly characterized. To better understand MDH, we manipulated its structure by inserting a point mutation into the flexible loop region at position 135, exchanging a lysine (Lys) to a phenylalanine (Phe). We hypothesized that mutating a positively charged amino acid (Lys) to an aromatic amino acid (Phe) would cause …