Organic Chemistry Commons^™

Synthesis And Characterization Of Amide Linked Triazolyl Glycolipids As Molecular Hydrogelators And Organogelators, Guijun Wang, Anji Chen, Hari P. R. Mangunuru, Jayasudhan Reddy Yerabolu

Chemistry & Biochemistry Faculty Publications

Carbohydrate based small molecular gelators are important classes of compounds which can form useful soft materials with many practical applications. Although many different types of effective gelators have been reported, the rational design of a molecular hydrogelator is still challenging. In this research, we combined the structural features of two classes of monosaccharide based molecular gelators and obtained a new class of glycolipids that can function as molecular gelators. These new compounds were synthesized by introducing a triazole functional group to a protected 2-glucosamine through Cu(i) catalyzed azide/alkyne cycloaddition reaction (CuAAC). A series of eighteen new glycolipids containing 4,6-O …

Synthesis Of New Fullerene Derivatives For Photovoltaic And Biological Applications, Edison Castro

Open Access Theses & Dissertations

Functionalized fullerenes exhibit improved solubility and different chemical and physical properties that allow applications in multiple fields such as photovoltaic and biological applications. Currently, perovskite solar cells (PSCs) are the most rapidly developing type of solar cells with certified efficiencies rising from 3.8% in 2009 to 22.1% in 2016. The good electron transporting and solution processable properties of most fullerene derivatives make them the most popular electron transporting materials (ETMs) in inverted perovskite solar cells (PSCs).

The work is reported in 11 chapters. We start with a fullerene overview followed by cleaver and elegant methodologies that allow the synThesis of …

Design, Cloning, And Expression Of Rat Preptin And Alanine Analogs, Jahbo M. Love

Theses and Dissertations

Alanine scanning mutagenesis was employed to determine the structural epitopes of preptin; a newly discovered polypeptide found on the proinsulin-like growth factor II. The alanine scanning mutagenesis was accomplished by the use of, cloning, affinity chromatography, gel electrophoresis, gene sequencing, and mass spectra. However, due to inconclusive results, more research is required before the epitopes can be elucidated.

Synthesis And Fluorescent Properties Of A New Flavonoid Compound, Ashley L. Ingle

Williams Honors College, Honors Research Projects

Flavonoids are highly luminescent compounds that are used in diagnosing and treating certain diseases.They are composed of two aromatic rings (ring A and ring B) and a six-membered heterocyclic pyran ring (ring C) that contains a carbonyl and hydroxyl group, which are responsible for unique photophysical characteristics associated with flavonoids. The target flavonoids (compound 1, or 1, and compound 2 or 2) were synthesized, purified and characterized by NMR spectroscopy. The photophysical properties of the flavonoid were investigated in varying solvents by using UV-vis and fluorescence spectroscopy. Such properties include Excited State Intramolecular Proton Transfer (ESIPT), Intramolecular Charge …

Plant-Fungi Chemgeography: Fungal Symbionts Are More Chemically Dissimilar Then Host Plants, Mitchell Beyer, Jonathan Craft

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Analysis Of Metabolites In The Urine Of Mice With Tyrosinemia Type 1 Using Nmr And Ms, Flora Eason

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Metabolic Investigations Of The Molecular Mechanisms Associated With Parkinson’S Disease, Robert Powers, Shulei Lei, Annadurai Anandhan, Darrell D. Marshall, Bradley Worley, Ronald Cerny, Eric D. Dodds, Yuting Huang, Mihalis I. Panayiotidis, Aglaia Pappa, Rodrigo Franco

Robert Powers Publications

Parkinson’s disease (PD) is a neurodegenerative disorder characterized by fibrillar cytoplasmic aggregates of α-synuclein (i.e., Lewy bodies) and the associated loss of dopaminergic cells in the substantia nigra. Mutations in genes such as α -synuclein (SNCA) account for only 10% of PD occurrences. Exposure to environmental toxicants including pesticides and metals (e.g., paraquat (PQ) and manganese (Mn)) is also recognized as an important PD risk factor. Thus, aging, genetic alterations, and environmental factors all contribute to the etiology of PD. In fact, both genetic and environmental factors are thought to interact in the promotion of idiopathic PD, but the mechanisms …

Mechanisms Of Heterogeneous Oxidations At Model Aerosol Interfaces By Ozone And Hydroxyl Radicals, Elizabeth A. Pillar-Little

Theses and Dissertations--Chemistry

Atmospheric aerosols play an important role in climate by scattering and absorbing radiation and by serving as cloud condensation nuclei. An aerosol’s optical or nucleation properties are driven by its chemical composition. Chemical aging of aerosols by atmospheric oxidants, such as ozone, alters the physiochemical properties of aerosol to become more hygroscopic, light absorbing, and viscous during transport. However the mechanism of these transformations is poorly understood. While ozone is a protective and beneficial atmospheric gas in the stratosphere, it is a potent greenhouse gas in the troposphere that traps heat near the Earth’s surface. It also impacts human heath …

Heterogeneous Base Metal Catalyzed Oxidative Depolymerization Of Lignin And Lignin Model Compounds, John Adam Jennings

Theses and Dissertations--Chemistry

With the dwindling availability of petroleum, focus has shifted to renewable energy sources such as lignocellulosic biomass. Lignocellulosic biomass is composed of three main constituents, lignin, cellulose and hemicellulose. Due to the low value of cellulosic ethanol, utilization of the lignin component is necessary for the realization of an economically sustainable biorefinery model. Once depolymerized, lignin has the potential to replace petroleum-derived molecules used as bulk and specialty aromatic chemicals. Numerous lignin depolymerization strategies focus on cleavage of β-aryl ether linkages, usually at high temperatures and under reductive conditions.

Alternatively, selective benzylic oxidation strategies have recently been explored for …

Formation Of The Ether Bridge In The Loline Alkaloid Biosynthetic Pathway, Minakshi Bhardwaj

Theses and Dissertations--Chemistry

Lolines are specialized metabolites produced by endophytic fungi, such as Neotyphodium and Epichloë species, that are in symbiotic relationships with cool-season grasses. Lolines are vital for the survival of the grasses because their insecticidal and antifeedant properties protect the plant from insect herbivory. Although lolines have various bioactivities, they do not have any concomitant antimammalian activities.

Lolines have complex structures that are unique among naturally occurring pyrrolizidine alkaloids. Lolines have four contiguous stereocenters, and they contain an ether bridge connecting C(2) and C(7) of the pyrrolizidine ring. An ether bridge connecting bridgehead C atoms is unusual in natural products and …

Acenes, Heteroacenes And Analogous Molecules For Organic Photovoltaic And Field Effect Transistor Applications, Devin B. Granger

Theses and Dissertations--Chemistry

Polycyclic aromatic hydrocarbons composed of benzenoid rings fused in a linear fashion comprise the class of compounds known as acenes. The structures containing three to six ring fusions are brightly colored and possess band gaps and charge transport efficiencies sufficient for semiconductor applications. These molecules have been investigated throughout the past several decades to assess their optoelectronic properties. The absorption, emission and charge transport properties of this series of molecules has been studied extensively to elucidate structure-property relationships. A wide variety of analogous molecules, incorporating heterocycles in place of benzenoid rings, demonstrate similar properties to the parent compounds and have …

Towards The Total Synthesis Of 7-Epi-Clusianone, Shubhankar Dutta

Theses and Dissertations--Chemistry

Polycyclic polyprenylated acylphloroglucinols (PPAPs) are plant- (Guttiferae) derived natural products. They have fascinating bicyclo[3.3.1]nonane-2,4,9-trione or [3.2.1]nonane-2,4,8-trione cores decorated with prenyl or geranyl groups. More than 200 PPAPs have been isolated, but only a few of them have been synthesized, although most of the synthesized PPAPs are of type A and have an exo substituent at C (7). Here, we are trying to make a type B 7-endo PPAP, 7-epi-clusianone. The synthetic plan involves an alkynylation–aldol strategy to construct the bicyclic core. Having established the bicyclic core, the synthesis presents a new challenge: the oxidation of a very hindered …

Regioselective Electrolytic 5,8-Difluorination Of Quinolines, Sean P. Spurlin

Honors College Theses

Over the past decade, synthesis of organofluorine compounds has become a mainstream research focus. The introduction of fluorine uniquely affects the biological properties of organic molecules such as making them more bioavailable, lipophilic and metabolically stable, and possibly increase the strength of a compound’s interactions with a target protein. Approximately 30% of agrochemicals and 20% of pharmaceuticals contain fluorine, including commonly prescribed drugs such as Lipitor, Lexapro and Prozac. This work describes the development of a new methodology to incorporate fluorine into organic compounds. Our new method involves a regioselective electrochemical 5,8-difluorination of quinolines using HF:pyridine as both the reagent …

Mild Hydrofunctionalizations Of Olefins Using More Cost-Effective Metal Catalysts, Alexander James Villani-Gale

Dissertations

The focus of this dissertation is the study of alkene hydroaylation reactions. In the first chapter, a review of the relevant literature concerning zinc- and iron-catalyzed hydroarylation of unsaturated bonds is presented. In chapter two, the development of a zinc-catalyzed hydroarylation of alkenes is presented, which is quickly followed by a detailed investigation into the probable mechanism. Chapter three discusses the development of an iron/silver-catalyzed arene prenylation reaction, followed by the development of an iron/zinc-catalyzed arene prenylation reaction. The final section of chapter three discusses the adaptation of the iron/zinc-catalyzed arene prenylation into an undergraduate organic teaching laboratory.

Thermal Conductivities Of Organic Semiconductors, Yulong Yao

Theses and Dissertations--Physics and Astronomy

Organic semiconductors have gained a lot of interest due to their ease of processing, low-cost and inherent mechanical flexibility. Although most of the research has been on their electronic and optical properties, knowledge of the thermal properties is important in the design of electronic devices as well. Our group has used ac-calorimetric techniques to measure both in-plane and transverse thermal conductivities of a variety of organic semiconductors including small-molecule crystals and polymer blends. For layered crystals composed of molecules with planar backbones and silylethynyl (or germylethynyl) sidegroups projecting between the layers, very high interplanar thermal conductivities have been observed, presumably …

Preparation And Evaluation Techniques Of Porous Materials And Mixed Matrix Membranes For Targeted Co2 Separation Applications, Tsemre Tessema

Theses and Dissertations

The use of porous sorbents for physisorptive capture of CO₂ from gas mixtures has been deemed attractive due to the low energy penalty associated with recycling of such materials. Porous organic polymers (POPs) have emerged as promising candidates with potential in the treatment of pre- and post- fuel combustion processes to separate CO₂ from gas mixtures. Concurrently, significant advances have been made in establishing calculation methods that evaluate the practicality of porous sorbents for targeted gas separation applications. However, these methods rely on single gas adsorption isotherms without accounting for the dynamic gas mixtures encountered in real-life applications. …

Preparation And Application Of Catalysts For The Stereospecific Reduction And Photooxygenation Of Olefins In Continuous Operations: A Novel Method For The Production Of Artemisinin, Daniel C. Fisher

Theses and Dissertations

Over the last two centuries, the discovery and application of catalysts has had a substantial impact on how and what chemicals are produced.Given their broad significance, our group has focused on developing new catalyst systems that are recoverable and reusable, in an attempt to reduce concomitant costs.

Our efforts have centered on constructing a recyclable chiral heterogeneous catalyst capable of effecting asymmetric hydrogenations of olefins with high stereoselectivity. A class of phosphinoimidazoline ligands, developed by researchers at Boehringer-Ingelheim, known as BIPI ligands, have proven efficacious in the asymmetric reduction of alkenes. However, these chiral ligands are homogeneous and coordinated to …

A Novel Synthesis And Subsequent Decyclization Of Iminothiozolidinones: Expansion Of Thiourea Chemistry For Biological Applications, Constance D. Franklin

Theses and Dissertations

Small molecule synthesis has become a valuable tool in the study of biological systems. Biologically active compounds can be designed based on well-characterized endogenous systems or they can be found through the screening of large libraries of small molecules. This work involves the development of a small library of cyclic thiourea-based small molecules by use of an unreported synthetic pathway. Briefly, parent thioureas were cyclized by reaction with bromoacetyl bromide, and one or two isomeric heterocycles were found to form. Further studies indicated that the reaction could be easily manipulated by temperature or solvent to effectively control the product distribution. …

The Synthesis Of Symmetric Polycyclic Aromatic Hydrocarbons And The Mesomorphic Properties Of Their Brominated Derivatives, Vanessa Bellemore

Theses and Dissertations (Comprehensive)

In this thesis, the synthesis of a series of brominated alkoxy-substituted trinaphthylenes was developed using a nickel-mediated Yamamoto coupling as the main step. Characterization of these compounds led to the discovery of a new set of broad range liquid crystals. They were found to undergo higher order transitions (i.e. glass phases/soft crystals/liquid crystal) via DSC, and also to decompose before reaching an isotropic liquid, as verified via thermogravimetric analysis. Polarized optical microscopy showed a texture characteristic of a columnar hexagonal mesophase. In addition, the aggregation in solution was studied using concentration dependent NMR studies, and the brominated-derivatives were determined to …

Formation Of Titan Aerosol From Co And Ch4, Tate Christensen

Honors Program Theses

In 1952 Stanley Miller and Harold Urey conducted an experiment that would simulate the conditions of early earth (Miller, 1953). The purpose was to observe the chemical origins of life, and the conclusion supported an earlier theory that such conditions favor the synthesis of more complex organic compounds from simpler inorganic molecules. The research conducted in Dr. Sebree’s lab is an extension of these early findings. It is believed that early Earth was composed mostly of nitrogen, carbon monoxide, carbon dioxide and methane as opposed to our atmosphere of nitrogen and oxygen today.

Saturn’s largest moon, Titan, has qualities relatively …