Chemistry Commons^™

Synthesis Of Bis(Imino)Pyridine Iron(Ii) Complexes And Development Of Bis(Imino)Pyridine Iron(Ii) Catalyzed Carbene Transfer Reactions, Ban Wang

Masters Theses & Specialist Projects

Metal catalysis of symmetric and asymmetric carbene transfer reactions has been widely applied in natural product synthesis and material science over years. Metal carbene can be easily generated from the extrusion of nitrogen under the catalysis of metal complexes to further undergo various organic reactions, O/N/C-H insertions, cycloadditions, and ylide formations. Currently, the dominant effective catalysts for carbene reactions are built with expensive precious metal, for example, rhodium, ruthenium, palladium, gold. Notably, the effective reactivity and enantioselectivity of the dirhodium(II) catalysts are researched and established over the decades. However, the use of precious metal catalysts is the major source of …

The Development Of An Integrated Simulation Model On Understandings On The Interaction Between Electromagnetic Waves And Nanoparticles, Xiaojin Wang

Masters Theses & Specialist Projects

To investigate the interaction between nanoparticles and electromagnetic waves, a numerical simulation model based on FEM was built in this thesis. Numerical simulation is an important auxiliary research method besides experiments. The optical properties of nanoparticles consist of scattering, absorption, and extinction, and in the case of nanoparticle suspension, the transmission is also involved. This thesis addressed two typical applications based on the established model, one was regarding the nanofluids for solar energy harvesting, and the other was regarding the optical properties of atmospheric soot. In the case of the nanofluids solar energy harvesting, the established model provided a convenient …

Quantification Of Tylosin Antibiotics In Cattle Waste, Appala Keerthi

Masters Theses & Specialist Projects

Antibiotics are used as prophylactic agents to promote growth and for treating infections in animals. However, the irrational use of antibiotics in livestock management is a significant cause of the development of antibioticresistant genes in the environment. Each year 2 million people suffer from the infections caused by bacteria which are resistant to antibiotics and 23,000 of these people are estimated to die because of antibiotic resistance. New drugs are continually coming into the market but are at the risk of developing resistance. Thus, there is a need for the development of analytical methods which can be used to monitor …

Synthesis Of A Platinum Triamine Complex And Its Interactions With Guanosine 5’- Monophosphate And N-Acetylmethionine, Manal El Masri

Masters Theses & Specialist Projects

Cisplatin (cis-diamminedichloroplatinum(II)) and its analogs are known to form 1,2-intrastrand cross-links with guanine bases that lead to DNA distortion and are responsible for cytotoxicity. Reaction with proteins, especially at methionine residues, could also be responsible for cytotoxicity (Sandlin, R. D. et al. 2010). A new tridentate platinum(II) complex with a piperazine ring was successfully designed and synthesized. In this complex, the platinum is coordinating to all three nitrogens of (1,2- dimethylaminoethylpiperazine), which makes it a Platinum triamine compound. A series of chemical reactions of this compound with guanosine 5’-monophosphate (5’-GMP) and N-acetylmethionine (N-AcMet) were conducted under different conditions. Reactions with …

Synthesis And Characterization Of Graphene-Family Mesoporous Nanomaterials For Themal Energy Harvesting And Sensing Applications, Romney Meek

Masters Theses & Specialist Projects

Graphene-family nanomaterials (GFNs) have attracted a great deal of attention both in academia and in industry for a range of applications relevant for homeland security. In this thesis, an array of graphene-based hybrid materials and aerogels are synthesized for use as novel thermo-electrochemical energy harvesters and for ascorbic acid biosensing devices. The graphene-family nanomaterials include graphene oxide-GO, thermally reduced GO-rGOth, nitrogenated functionalized graphene-NFG, graphene aerogel-GA, nitrogen-doped graphene aerogel-NGA, multi-walled carbon nanotube aerogel-MWCNT, single-walled carbon nanotube aerogel-SWCNT, graphene and nanotube combined ‘hybrid’ aerogels-Gr:(SW/MW)CNT of various ratios, along with multilayered nanostructured architectures such as gold (AuNP) and silver nanoparticles (AgNP) decorated NFG …

Developing A New Sensing Technology For Double-Stranded Dna Detection Utilizing Engineered Zinc Finger Proteins And Nanomaterials, Dat Thinh Ha

Masters Theses & Specialist Projects

A specific double-stranded DNA sensing system is of great interest for diagnostic and other biomedical applications. Zinc finger domains, which recognize double-stranded DNA, can be engineered to form custom DNA-binding proteins for recognition of specific DNA sequences. As a proof of concept, a sequence-enabled reassembly of TEM-1 β- lactamase system (SEER-LAC) was previously demonstrated to develop zinc finger protein (ZFP) arrays for the detection of a double-stranded bacterial DNA sequence. Here, we implemented the SEER-LAC system to demonstrate the direct detection of pathogenspecific DNA sequences present in E. coli O157:H7 on the lab-on-a chip. ZFPs customdesigned to detect shiga toxin …

Photochemical Investigation Of High-Valent Metal-Oxo Intermediates Containing Corrole And Light-Harvesting Porphyrin Ligands, Jonathan Malone

Masters Theses & Specialist Projects

In enzymatic and synthetic catalytic oxidations, high-valent iron-oxo intermediates play a vital role as the active oxidant. In this regard, many synthetic metal catalysts are designed as biomimetic models to resemble the active site of Cytochrome P450 enzymes (P450) which are the predominant oxidation catalysts in nature. Vitamin B12 cofactors, with a corrole-like structure corrin, are also utilized in some of the more difficult reactions in nature such as rearrangement and reductase reactions.

In this work, application of the promising photochemical method to corrolecontaining ligands systems showed much success in the generation of manganese(V)-oxo corrole intermediates using two electron-deficient corrole …

Molecular Assembly Of Monolayer-Protected Gold Nanoparticles And Their Chemical, Thermal, And Ultrasonic Stabilities, Steven Ray Isaacs

Masters Theses & Specialist Projects

Gold monolayer-protected nanoclusters (MPCs) with average diameters of 1-5 nm protected by alkane- and arenethiolates were synthesized. Mixed-monolayer protected nanoparticles (MMPCs) were prepared by functionalizing hexanethiolate-protected MPCs with either 11-mercaptoundecanoic acid (MUA-MMPC), 11-mercaptoundecanol (MUO-MMPC), or 4-aminothiophenol (ATP-MMPC) using ligand place exchange. Presentation of various chemical reagents such as nucleophile, acid, or base and change in physical environment through ultrasonic and thermal irradiation resulted in changes to particles and their physical properties. Thermogravimetric analysis (TGA) was used to measure maximum temperature of the derivated thermogravimetric peaks (Tmax,DTG) as a means of comparing temperature dependence of mass loss. The absorption spectrum within …

Visible Light Generation Of High-Valent Corrole-Manganese(V)-Oxo Intermediates And Biomimetic Studies Of The Oxidation Of Organic Sulfides Catalyzed By Manganese Corroles With Iodobenzene Diacetate, Davis Ray Ranburger

Masters Theses & Specialist Projects

High-valent transition metal-oxo intermediates play essential roles as active oxidizing species in enzymatic and biomimetic catalytic systems. Extensive research has been conducted on a variety of transition metal catalysts being studied as models for the ubiquitous cytochrome P450 enzymes. In doing so, the production of enzyme-like oxidation catalysts and probing studies on the sophisticated oxygen atom transfer mechanism are taking place.

In this work, visible-light irradiation of highly-photo-labile corrole-manganese(IV) bromates and chlorates was studied in two corrole systems with differing electronic environments, i.e. 5,10,15-trisphenylcorrole (H3TPC) and 5,10,15- tris(pentafluorophenyl)corrole (H3TPFC). In both systems, homolytic cleavage of the O- …

Biomimetic Studies Of Oxidation Reactions By Metalloporphyrins Through Ligand Effect And Kinetic Studies Of Photo-Generated Porphyrin-Iron(Iv)- Oxocompound Ii Models, Dharmesh J. Patel

Masters Theses & Specialist Projects

High-valent iron(IV)-oxo porphyrins are the central oxidizing species in hemecontaining enzymes and synthetic oxidation catalysts. Many transition metal complexes have been extensively studied as models of the ubiquitous cytochrome P450 enzymes to probe the sophisticated oxygen atom transfer (OAT) mechanism as well as to invent enzyme-like oxidation catalysts. In this work, two metalloporphyrin complexes have been successfully synthesized, and spectroscopically characterized. A new photochemical entry to porphyrin-iron(IV)-oxo derivatives, commonly referred to as compound II models, was also investigated in two porphyrin ligands that differ in electronic and steric environments. As determined by their distinct UV-vis spectra and kinetic behaviors, iron(IV)-oxo …

Kinetic Modeling Of The Atmospheric Photooxidation Of Reduced Sulfur And Nitrogen Compounds, Jesus Alejandro Berlanga

Masters Theses & Specialist Projects

Atmospheric aerosols encapsulate a wide variety of particles with different compositions, sizes and sources of origin. They also directly and indirectly affect climate by their interactions with sunlight, clouds, atmospheric chemical species, and even other suspended particles. To understand the atmospheric aerosol processes and the effects they have in global and regional climate is of utmost importance for the future establishment of environmental regulations and emission policies that affect aerosol precursor compounds in an effective and beneficial manner. In particular, aerosols are known to be formed from emissions from human activities, such as fossil fuel burning, agriculture, or concentrated animal …

Foutier Transform Infrared Spectroscopy Instrumentation And Integration With Thermogravimetry, Junjie Xiang

Masters Theses & Specialist Projects

To discover the potential of IR spectroscopy and explore the details of FTIR instrumentation, a FTIR was built from most basic parts to provide access to every aspect of a IR spectrometer including the hardware and software. The optical system followed the most widely used double-interferometer design. The software control system was developed with LabVIEW to perform data acquisition of the detectors, data processing and controls of the actuators. The FTIR built will be able to provide a full optical IR spectroscopy platform which has a complete control and data acquisition system and can be continuously improved in accuracy and …

Secondary Electronic And Solvent Effects On Regiospecific P-Bromination Of Aromatic Systems, Selahaddin Gumus

Masters Theses & Specialist Projects

Bromoarenes are important aromatic building blocks that are commonly used to synthesize various functional compounds in pharmaceutical, agrochemical and related industries.^1,2 This great demand for bromoarenes makes their preparation a widely studied area of synthetic organic chemistry. However, further understanding of the reactivity and regiochemistry of aromatic functionalization reactions is still necessary, as much about the secondary substitution and solvent effects remain unknown.

Resonance Theory is a widely used theoretical model to predict the regiospecifity and reactivity of the bromination of various aromatic compounds.³ The reactivity and regiospecificity of many substituted aromatic compounds is well explained using resonance …

Imidazolium Ionic Liquids As Multifunctional Solvents, Ligands, And Reducing Agents For Noble Metal Deposition Onto Well-Defined Heterostructures And The Effect Of Synthetic History On Catalytic Performance, Michael Drake Ballentine

Masters Theses & Specialist Projects

1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([BMIM]Tf2N) was investigated as a multifunctional solvent, ligand, and reducing agent for platinum deposition onto well-defined CdSe@CdS nanorods. Platinum deposition was carried out thermally and photochemically using Pt(acac)2 as the metal precursor. Thermal deposition was investigated in [BMIM]Tf2N with and without addition of a sacrificial reducing agent, and product topology was compared with the products obtained from polyol reduction using 1,2-hexadecanediol, oleic acid, and oleylamine in diphenyl ether. Photochemically induced platinum deposition was carried out at room temperature in [BMIM]Tf2N, and product topology was compared with the photodeposition products obtained from a toluene dispersion. Thermal deposition of platinum …

Temperature And Electric Field Dependency Of Asymmetric Stretching Of Nitrate And Carbonate Ions, Konnor Jones

Masters Theses & Specialist Projects

Photolysis of nitrate ion in the natural environment produces NO, NO2, and O3, releasing these toxic gases into the atmosphere. Work done by other groups has shown ionic strength dependence of the ratio of products from photolysis of aqueous nitrate ion. To better understand the kinetic mechanisms of nitrate photolysis, the effects that ionic strength in solution have on nitrate ion symmetry breaking are needed. Different solvation environments induce nitrate bonding motifs that may be correlated to the product ratio. Fourier-transform infrared spectra of aqueous nitrate–ion solutions were obtained over a range of temperatures for several total electrolyte concentrations. The …

Nano/Submicro-Structured Iron Cobalt Oxides Based Materials For Energy Storage Application, Hongyan Gao

Masters Theses & Specialist Projects

Supercapacitors, as promising energy storage devices, have been of interest for their long lifespan compared to secondary batteries, high capacitance and excellent reliability compared to conventional dielectric capacitors. Transition metal oxides can be applied as the electrode materials for pseudocapacitors and offer a much higher specific capacitance. Co3O4 is one of the most investigated transition metal oxides for supercapacitor. Besides simple monometallic oxides, bimetallic transition oxides have recently drawn growing attention in electrochemical energy storage. They present many unique properties such as achievable oxidation states, high electrical conductivities because of the coexistence of two different cations in a single crystal …

Photochemical Generation And Kinetic Studies Of High-Valent Metal-Oxo Intermediates Supported By Corrole And Porphyrin Ligands, Ngo Fung Lee

Masters Theses & Specialist Projects

High-valent transition metal-oxo intermediates are of fundamental importance because of their central role as active oxidizing species in enzymatic and synthetic catalytic oxidations. Many transition metal catalysts have been extensively studied as models of the ubiquitous cytochrome P450 enzymes to probe the sophisticated oxygen atom transfer mechanism as well as to invent enzyme-like oxidation catalysts.

In this work, photolysis of highly photo-labile corrole-manganese(IV) bromates or nitrites by visible light was studied in two corrole systems with different electronic environments. The corrole systems under studied include 5,10,15- tris(pentafluorophenyl)corrole (TPFC) and 5,10,15-triphenylcorrole (TPC). As observed in both systems, homolytic cleavage of O-Br …

Synthesis,Structure And Properties Of Ruthenium Polypyridyl Metalloligand Based Metal-Organic Frameworks, Mamatha Polapally

Masters Theses & Specialist Projects

Metal-organic frameworks (MOFs) have been extensively studied because of their amazing applications in gas storage, purification, photocatalysis, chemical sensing, and imaging techniques. Ruthenium polypyridyl complexes have been broadly considered as photosensitizers for the conversion of solar energy and photoelectronic materials. With this aspect, we have synthesized three new ruthenium polypyridyl based MOFs ([Ru(H2bpc)Cu(bpc)(Hbpc)2(H2O)]·5H2O (1), [Ru(H2bpc)(Fe(bpc)(Hbpc)2(H2O)2]·6H2O (2) and [Ru(H2bpc)Ni(bpc)(Hbpc)2(H2O)2]·6H2O (3)) from ruthenium(III) chloride, bpc (2,2’- bipyridine-4,4’-dicarboxylic acid) ligand, and 3d M(II) metal ions (M(II)= Cu(II), Fe(II), Ni(II)). These MOFs were synthesized under hydro or solvothermal conditions by using water, ethanol or methanol as solvents. The crystal structures of the new compounds …

Graphene-Based ‘Hybrids’ As High-Performance Electrodes With Tailored Interfaces For Alternative Energy Applications: Synthesis, Structure And Electrochemical Properties, Mayme Marie Van Meveren

Masters Theses & Specialist Projects

Technological progress is determined to a great extent by developments of novel materials from new combinations of known substances with different dimensionality and functionality. We investigate the development of 3D ‘hybrid’ nanomaterials by utilizing graphene based systems coupled with transition metal oxides (e.g. manganese oxides MnO2 and Mn3O4). This lays the groundwork for high performance electrochemical electrodes for alternative energy owing to their higher specific capacitance, wide operational window and stability through charge-discharge cycling, environmental benignity, cost effective, easily processed, and reproducible in a larger scale.

Thus far, very few people have investigated the potential of combining carbon sheets that …

An Expedited, Regiospecific Para-Bromination Of Activated Aryls, Kathryn E. Dudley

Masters Theses & Specialist Projects

Electrophilic Aromatic Substitution (EAS) is one of the most frequently used aryl substitution methods. Aside from the fact that most EAS reactions require an acid and an oxidizer to proceed, the reactions involving activated aryls typically produce a mixture of ortho- and para- products as well as an ortho-/para- disubstituted product. Regiospecificity in aromatic substitution is key in the production of many compounds in a variety of disciplines. Since EAS is one of the most often used substitution methods, it is extremely important to develop an efficient method for regiospecific substitutions. Previous research developed a method of ortho-substitution by using …

The Effects Of Carrier Ligands On Cisplatin Binding To Cysteine And Methionine, Adam C.R Smith

Masters Theses & Specialist Projects

We have reacted several derivatives of the anticancer drug cisplatin with N-acetyl-Lcysteine (N-AcCys) and N-acetyl-L-methionine (N-AcMet), which are two of the primary amino acid targets of platinum. NMR spectroscopy was used to monitor the reactions and determine the effect the different ligands would have on the platinum reactivity. Several of the platinum compounds were tested at pH of 4 and 7, and with platinum:amino acid ratios of 1:1, 2:1 and 1:2. Competition reactions between cysteine and methionine were done to confirm which would react with the platinum compound first. [Pt(dien)(NO3)]+ reacts faster with methionine than with cysteine at both pH …

Synthesis, Characterization, And Properties Of Graphene-Based Hybrids With Cobalt Oxides For Electrochemical Energy Storage And Electrocatalytic Glucose Sensing, Sara C. Botero Carrizosa

Masters Theses & Specialist Projects

A library of graphene-based hybrid materials was synthesized as novel hybrid electrochemical electrodes for electrochemical energy conversion and storage devices and electrocatalytical sensing namely enzymeless glucose sensing. The materials used were supercapacitive graphene-family nanomaterials (multilayer graphene-MLG; graphene oxide-GO, chemically reduced GO-rGO and electrochemical reduced GOErGO) and pseudocapacitive nanostructured transition metal oxides including cobalt oxide polymorphs (CoO and Co3O4) and cobalt nanoparticles (CoNP). These were combined through physisorption, electrodeposition, and hydrothermal syntheses approaches. This project was carried out to enhance electrochemical performance and to develop electrocatalytic platforms by tailoring structural properties and desired interfaces. Particularly, electrodeposition and hydrothermal synthesis facilitate chemically-bridged …

Environmentally Friendly Synthesis Of Transition Metalorganic Hybrid Nanocomposites, Aubrey N. Penn

Masters Theses & Specialist Projects

Research on metal nanoparticles (MNPs) synthesis and their applications for optoelectronic devices has been a recent interest in the fields of nanoscience and nanotechnology Photovoltaics are one of such systems in which MNPs have shown to be quite useful, due to unique physical, optical, magnetic, and electronic properties, including the metal nanoparticles synthesized in this research.

Owing to the challenges with the most common physical and chemical methods of preparing MNPs, including the use of high temperatures, toxic reducing agents, and environmentally hazardous organic solvents, there is a critical need for a benign synthesis procedure for MNPs. In this work, …

Regiospecific P-Bromination Of Activated Aromatic Systems – Greener Approach, Elnaz Jalali

Masters Theses & Specialist Projects

The halogenated derivatives of heterocyclic compounds (haloarenes) are highly utilized in many fields of chemistry, including drug discovery, medicinal, and material chemistry. There are a variety of ways to functionalize an aromatic system and introduce halogen substituent into the ring. However, electrophilic aromatic substitution (EAS) has been the focus of growing attention, particularly for electronrich substrates.

Electrophilic aromatic bromination protocols are one of the most important electrophilic aromatic substitution reactions. However, preparation of bromoarenes classically recommends the use of highly oxidative agents along with utilizing various metal catalysts in a halogenated solvent. The corrosive and toxic nature of these reagents …

Detection And Quantitation Of Tetracycline Antibiotics In Agricultural Swine Wastes, Ali Jamal Abdulrheem

Masters Theses & Specialist Projects

The spread of tetracyclines through agricultural systems is causing the present bacteria to develop antibiotic resistance. The spread of this bacteria, as well as the tetracycline antibiotics in the environment is dangerous because these antibiotics pose health hazards for humans. The overuse of antibiotics, which are added to livestock feed, results in the antibiotics being released into the environment via animal feces. In this research, we have attempted to design an analytical method to isolate antibiotics from agricultural wastes with subsequent detection using liquid chromatography and mass spectrometry (LC-MS). The antibiotics investigated in this study were tetracycline, chlortetracycline, and oxytetracycline. …

Tio2/Pdms Buoyant Photocatalyst For Water Remediation And Cu‑Rbs Organic/Inorganic Hybrid For Thermoelectric Applications, John R. Bertram

Masters Theses & Specialist Projects

Two novel materials have been developed: TiO2/poly(dimethylsiloxane) (PDMS) beads as buoyant photocatalyst materials for water remediation, and copper rhodamine‑B silane (Cu‑RBS) as an n ‑type organic/inorganic hybrid for thermoelectric applications. The approach to incorporate TiO2 into low‑density PDMS beads addresses many of the challenges traditionally encountered when creating buoyant photocatalysts, an area which is crucial for wide‑spread remediation of water resources, including natural bodies of water. The performance and reusability of the buoyant photocatalyst materials, demonstrated by using methylene blue as a model degradation target, is strong enough for environmental application. The use of a kinetic model and the introduction …

Synthesis, Kinetic And Catalytic Studies Of Manganese Complexes With Corrole And Porphyrin Ligands, Haleh Jeddi

Masters Theses & Specialist Projects

High-valent transition metal-oxo intermediates play a significant role in the catalytic cycle of the ubiquitous cytochrome P450 enzymes and in biomimetic catalytic systems. In this work, manganese(III) porphyrin and corrole systems (2) were synthesized and characterized by UV-vis absorbance and 1H-NMR, matching literaturereported spectroscopic data. Manganese(V)-oxo corroles (3) and a manganese(IV)-oxo porphyrin (4) were successfully generated by chemical oxidation using mchloroperoxybenzoic acid (m-CPBA), and their oxidation reactions with organic reductants were comparatively investigated. Results from single-turnover kinetic studies indicate that in the tris(pentafluorophenyl)corrole system (3a), the active oxidizing intermediate differs in different solvents. The active oxidizing intermediate in acetonitrile is …

Effects Of Binding Affinity Between Bovine Serum Albumin And Platinum Drugs, Nathan Puckett

Masters Theses & Specialist Projects

Platinum complex drugs such as cisplatin have been used as highly successful chemotherapy drugs since the 1970s. We are interested in how the ligands attached to cisplatin analogs influences their reactivity with biologically relevant targets along with time and amount. For this study, reactions were conducted to determine the reactivity between different platinum compounds and the protein bovine serum albumin. Various platinum compounds with different ligands were reacted in varying amounts with albumin in ammonium acetate buffer for either 1 hour, 4 hours, or 24 hours. Each reaction was quenched after the designated reaction time by dialysis and the platinum …

In Situ Ion Exchange In A Micro-Porous Transition Metal Silicate Framework, Jason M. Lively

Masters Theses & Specialist Projects

Ion selectivity of minerals has traditionally been utilized in industry as a catalyst, metal separation, and environmental reclamation/sequestration tool. There is an increased interest in understanding ion selectivity mechanisms of micro-porous minerals and mineral-like structures and how they can be applied in various industries: environmental and, potentially, pharmaceutical. This study seeks to understand the ion exchange mechanisms in micro-porous zirconosilicates using time-resolved Raman spectroscopy and X-ray diffraction. The thesis material was exchanged with H+, Na+, K+, and Cs+ in order to better understand structural changes as well as the influence of the H+-bonding during the exchange process. It is hypothesized …

Feasibility Of The Use Of Neutron Activation Analysis Techniques In An Underwater Environment, Michael D. Chick

Masters Theses & Specialist Projects

Elements when bombarded with neutrons emit a gamma ray that is characteristic of the isotope that underwent a neutron induced nuclear reaction; this is known as neutron activation. The characteristic gamma energy of an isotope can then be detected and recorded. One can then analyze the gamma energies captured and determine the elemental makeup of the sample. This form of analysis can be used in an underwater environment making it potentially a valuable tool for agencies tasked with maritime security of ports and waterways, or clean-up operations. This thesis will focus on the feasibility of neutron interrogation using pulsed fast/thermal …