Organic Chemistry Commons^™

Synthesis And Characterization Of Transition Metal Scorpionate Complexes For Redox Shuttle Applications In Dye-Sensitized Solar Cells, Chase Lance

Honors Theses

Given the rising global energy demands, alternative renewable energy sources are currently being investigated. The most appealing renewable energy source is solar energy, and dye-sensitized solar cells (DSSCs) in particular are an attractive technology. DSSCs have traditionally utilized iodide/triiodide as the redox mediator couple, which exhibits high efficiencies and fast regeneration of the oxidized dye with little recombination. Recently, the use of alternative redox couples based on transition metal complexes has been studied as a promising substitute due to the tunable design of these complexes. In this study, tridentate tris(pyrazolyl)borate and tris(pyrazolyl)methane ligands with first-row transition metals were designed and …

N-Terminal Imine Derivatization For Enhanced De Novo Peptide Sequencing: A Study Of The Fragmentation Pattern Generated From Cid Of Peptide-Imines, Khiry L. Patterson

Electronic Theses and Dissertations

In this work, the fragmentation pattern derived from model peptides derivatized to create N-terminal imines (Schiff bases) were evaluated. Collision-induced dissociation of the protonated peptide-imines ([M+H]⁺) generally produced complete series of the sequence informative a_n and b_n ions, now undoubtedly characteristic of the peptide ion species. A novel product ion was also observed, denoted the y^ǂ ion, determined by IRMPD spectroscopy and density functional theory to be generated from the elimination of the N-terminal amino acid residue despite the N-terminal modification. It was concluded the pathway involved a nucleophilic attack by an amide nitrogen and …

New Synthetic Transformations Utilizing Silyloxyallyl Cations And Epoxonium Ions As Reactive Intermediates, Alexander Houston Cleveland

LSU Doctoral Dissertations

The development of new chemical transformations is of paramount importance in organic chemistry. In fact the study and creation of new reactions often uncovers new chemical reactivities and creates a new area of chemistry. The purpose of this dissertation is to present the development of new synthetic reactions that were uncovered through previous discoveries. Additionally the underlying theme of this work relies on the intermediacy of cationic reactive intermediates such as silyloxyallyl cations and epoxonium ions. Chapters 1 and 2 present the reactivity of novel silyloxyallyl cations. These cationic species are generated via the mild ionization of a-hydroxy silylenol ethers …

Recombinant Expression Of Preptin Analogs For Alanine Scanning Mutagenesis Of Residues 27-29, Tehgan N. Anguilm

Theses and Dissertations

The novel peptide preptin consists of 34 amino acid residues corresponding to Asp⁶⁹-Leu¹⁰² of proinsulin-like growth factor E-peptide. Preptin has been isolated from pancreatic beta cells, and it has been found to exhibit both metabolic and mitogenic activities. This makes preptin an attractive candidate to treat insulin-independent diabetes and osteoporosis. Alanine scanning mutagenesis was utilized to substitute an alanine for residues Trp²⁷, Arg²⁸, and Gln²⁹ of preptin in order to ultimately study the structure-activity relationship of these residues to preptin’s metabolic activity.

A Cascade Reaction Of Cinnamyl Azides With Acrylates Directly Generates Tetrahydro-Pyrrolo-Pyrazole Heterocycles, Angela S. Carlson, En Chih Liu, Joseph J. Topczewski

Chemistry Faculty Research & Creative Works

Developing reactions to generate complex and modular building blocks in a concise and direct fashion remains a contemporary synthetic challenge. This work describes a stereoselective cascade reaction between allylic azides and acrylates that directly generates tetrahydro-pyrrolo-pyrazole ring systems. These products contain up to four contiguous stereocenters, two of which may be tetrasubstituted carbon atoms attached to a nitrogen atom. Over 30 examples are provided with an average isolated yield of 71% (ranging from 40% to 94%). The reaction was easily scaled to use more than one gram of starting material, and the products can be readily diversified.

Toxicity Analysis Of 2’-Deoxyguanosine-N2-6-Aminopyrene And 2’-Deoxyguanosine-N2-8-Aminopyrene In Escherichia Coli, Emily Janeiro

Honors Scholar Theses

Cancer is a disease that stems from genomic errors that are not corrected properly by cellular repair mechanisms. Errors are more likely to form when organisms are subjected to DNA damage by mutagenic compounds. 1-Nitropyrene, a nitrated polycyclic aromatic hydrocarbon (nitro-PAH), has been shown to be a potent mutagen that causes cancer. Nitro-PAHs can arise from diesel exhaust products in the environment. Out of all nitro-PAHs, 1-nitropyrene is found in largest quantities in the environment. This poses a great need to study its effects biochemically in order to address its toxicity in DNA. Other nitropyrene derivatives, including 1,6-dinitropyrene and 1,8-dinitropyrene, …

Mesoporous Adsorbents For Perfluorinated Compounds, Bertha Lotsi

Electronic Theses and Dissertations

Effective adsorbents for polyfluorinated compounds (PFCs) were successfully prepared. And they were tested in the adsorption of perfluorooctanoic and perfluorooctanesulfonic acids. Bridged silsesquioxanes containing secondary and tertiary amino groups were synthesized by sol-gel condensation of bis[3-(trimethoxysilyl)propyl]amine and bis[3-(methylamino)propyl]-trimethoxysilane in acidic media with surfactants. Obtained materials are mesoporous with a high BET surface area. They combine high structural stability with a high concentration of surface amino groups serving as adsorption sites. Batch adsorption tests demonstrated their extremely high adsorption capacity on PFCs: in some experiments, it reached up to 88% of the adsorbent weight. Adsorption of PFCs changed the surfaces of …

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 …

The Synthesis Of Urethane Acrylate Resin From Palm Fatty Acid Distillate And Some Mechanical Properties, Kim Teck Teo

Student Works (2020-2029)

Depletion of petroleum reserves and increasing environmental concerns have stimulated the efforts to explore materials from readily available, renewable natural resources, such as carbohydrates, oils, fats and proteins. Plant oil and its fatty acids are promising renewable resources to produce environmentally friendly polymeric materials. Palm oil is a major crop in Malaysia and consequently palm fatty acid distillate (PFAD) has been an abundant by-product during the refinery process. PFAD could be a renewable raw material for industrial application. Thus, we develop new PFAD-based acrylate resins UV curable for coatings applications. The resins could be produced by two approaches. Firstly, mixtures …

Immobilization Of Phosphotungstic Acid On Silica Surface For Catalytic Alkylation Of Aromatic Compounds, Anastasia Kuvayskaya

Electronic Theses and Dissertations

Superacidic mesoporous materials containing covalently embedded PTA were synthesized by sol-gel method. Tetraethyl orthosilicate (TEOS) and phosphotungstic acid (PTA) were used as precursors in the synthesis, ionic and nonionic surfactants were used as pore-forming agents, the reaction proceeded in acidic media. TEM images revealed mesoporous structure with embedded PTA clusters. FT-IR spectra of obtained materials contained characteristic bands of PTA at 957 cm-1. Synthesized catalysts had high BET surface area and high concentration of acidic sites. Alkylation of 1,3,5-trimethylbenzene by 1-decene demonstrated high catalytic activity. The catalyst obtained with Pluronic P123 as a template was the most effective and resulted …

Improving Biodiesel Through Pyrolysis: Direct Dynamics Investigations Into Thermal Decomposition Of Methyl Linoleate, Michael Bakker

Graduate Theses/Dissertations

Dependence on petroleum and petrochemical products is unsustainable as it is both a finite resource and environmentally hazardous. Biodiesel is a proposed alternative, but has complications including possessing poor cold weather operability and lacking the ability to supplement other petrochemical products (e.g., ethylene, hexane, etc.) relied upon in society. Pyrolysis of biodiesel has demonstrated the formation of smaller hydrocarbons comprising many of these petrochemical products. Our aim is to computationally simulate the pyrolysis of methyl linoleate, the most prevalent component in biodiesel formed in the US (from soybean). We make use of unimolecular direct dynamics describing intramolecular processes, introducing Temperature …

Surface Chemistry And Surface Properties Of Energetic Nitrocellulose (Nc), Henry Grau

Seton Hall University Dissertations and Theses (ETDs)

This research describes an investigation into the wettability of nitrocellulose (NC), most importantly to nitroglycerin (NG), which are key components of formulations used to propel military ammunition. NG demonstrates complete wetting of NC and, overtime, NG sweats on the NC surface and leaks out. The leaking out of NG from the solid formulation is a known cause of fires and explosions resulting from storage. The origin of this research is inspired by the need to engineer a solution to leakage problems of energetic plasticizer in NC based propellant. While searching for a viable material for a specific application, we journeyed …

Structure Activity Relationship (Sar) Studies Of Neurotoxin Quinoline-Derivatives, Dylan Smeyne

Honors College Theses

Structure activity relationship (SAR) studies are performed in order to identify the core structure that is responsible for the biological activity of an organic molecule. Recently, we have synthesized a drug prototype which contains several functional groups, such as an alcohol, an ester, a fluorine, and an aromatic ring. While studying in vivo toxicity of this molecule in zebrafish (Danio rerio) embryo, we observed that it has a unique biological activity that causes a sudden inactivity in embryo movement. Continued investigation revealed that this molecule blocks sodium channels in neurons causing a temporary anesthesia in Danio rerio embryo. The biological …

174— Developing Oxidation Of Alcohols In Sand, John Lepore, Stephanie Alvarez Merlos, Katelynn Dux, Theresa Lam

GREAT Day Posters

We present the oxidation of alcohols into aldehydes and ketones using (NH4)2Cr2O7 in sand. Several alcohols undergo oxidation using an appropriate solvent to afford aldehyde and ketones in good yields. The reactions were analyzed by TLC, 1H and 13C-NMR. The developed reaction is also compared to reactions done using silica gel.

Synthesized Tripodal Amine As Potential Anti-Cancer Therapeutic, Abigail G. Mcnamee

Honors College Theses

Cancer remains a prevalent disease today. This disease may manifest itself in many different ways and affect a variety of tissues with everything from the brain to the blood. With this wide diversity of cancer types, treatment can be complicated since there is not a “one size fits all” treatment for the disease. Surgery, radiation, and chemotherapy are all options that must be weighed with their benefits and side effects. Ultimately though, there are not enough effective treatment options available for every type of cancer. This leaves many with the grim prognosis of never being cured. With this clear need …

Identification Of Histone H4-Based Peptoids As Inhibitors Of Prmt1, Megan Demart, Molly Dubose, Sarah Mann, Corey Causey Phd, Bryan Knuckley Phd

Showcase of Osprey Advancements in Research and Scholarship (SOARS)

Protein Arginine Methyltransferases (PRMTs) are a family of 11 mammalian enzymes characterized by the post-translational methylation of arginine residues in the histone tail. The majority of the 11 members of the PRMT family are divided into two main types, Type I and Type II. PRMT1, the major Type I isozyme, catalyzes the formation of asymmetrically dimethylated arginine (ADMA). PRMT1 activates transcription of cancer genes. Peptoids, or poly-N-substituted glycine’s are a class of oligomers whose side chains are appended to the nitrogen atom of the peptide backbone rather than the alpha carbon. Kinetic parameters were conducted for both peptide and peptoid …

New Synthetic Methodology Using Base-Assisted Diazonium Salts Activation And Gold Redox Catalysis, Abiola Azeez Jimoh

USF Tampa Graduate Theses and Dissertations

Over the past two decades, homogeneous Au(I) catalysis has been a valuable synthetic tool for activating a series of unsaturated carbon-carbon bonds towards nucleophilic attack. Despite this progress, Au(I/III) redox chemistry has not been well explored. This is largely due to the challenges associated with the high oxidation potential of gold. Hence, the need for an efficient and safe method for Au oxidation.

Herein, a base-assisted diazonium salt activation has been used to facilitate Au redox reactions under mild reaction conditions. This oxidative coupling method afforded functional isoxazolines with good to excellent yields, while the alternative photoactivation method provided trace …

Monitoring And Identifying The Rhodamine 6g-Hydroxide Ion Reaction Using In-Situ, Surface-Enhanced Raman Spectroscopy, Ryan Lamb

Masters Theses & Specialist Projects

An effective method for monitoring chemical reactions is necessary to better understand their mechanisms and kinetics. Effective reaction monitoring requires a spectroscopy technique with fast data acquisition, high sensitivity, structure-to-spectrum correlation, and low solvent interference. Surface-enhanced Raman spectroscopy (SERS) provides these features, which makes it a valuable tool for monitoring reactions. To obtain the Raman enhancement, metallic nanostructures typically made of silver or gold are aggregated using a salt. The nanoparticles aggregates must then be stabilized using a surfactant to use this method in situ due to eventual nanoparticle precipitation. In this study, gold nanoparticles stabilized with sodium dodecyl sulfate …

Dissipation Of Benzobicyclon And Benzobicyclon Hydrolysate In A Louisiana Rice Field, Xavier Poole

LSU Master's Theses

Pesticide resistance in rice fields is an ongoing issue that has resulted in the development and use of pesticides with new modes of action. Benzobicyclon is the first registered hydroxyphenylpyruvate(HPPD)-inhibiting pesticide in the United States and has gained attention as a resistance management strategy to control weed pests in rice fields. Understanding the environmental fate and dissipation mechanisms of benzobicyclon is important due to the unique rotation of rice and crayfish in Louisiana on the same fields. Benzobicyclon persistence into the crayfish growing seasons may lead to unintended consequences for crayfish growth and production, assuming there is toxicity to crawfish. …

Assessing The Correlation Of Microscopy-Based And Volumetry-Based Measurements For Resin Swelling In A Range Of Potential Greener Solvents For Spps, Jordan K. Magtaan, Marc Devocelle, Fintan Kelleher

Articles

The degree of resin swelling in a particular solvent system is one of the critical parameters for SPPS, and for solid phase synthesis, in general. Methods used for measuring the degree of resin swelling include microscopy-based and volumetry-based methods. This study describes, and compares, the use of both methods for a number of commercially available resins commonly used in SPPS, with a range of solvents which have been identified in the literature as “greener” than DCM, DMF and NMP. The results were analysed by statistical methods and a significant correlation between the two distinct methods has been demonstrated for the …