Chemistry Commons^™

Bismuth(Iii) Bromide In Organic Synthesis. A Catalytic Method For The Allylation Of Tetrahydrofuranyl And Tetrahydropyranyl Ethers, Ram Mohan, Scott Krabbe, Veronica Angeles

Scholarship

A bismuth bromide-catalyzed (10.0 mol %) multicomponent reaction involving the allylation of THF- and THP-ethers, followed by in situ derivatization with acetic anhydride to generate highly functionalized esters has been developed under solvent-free conditions. To the best of our knowledge, this is the first report of a catalytic procedure for the allylation of THF- and THP-ethers to yield ring-opened products.

Iron(Iii) Tosylate-Catalyzed Deprotection Of Aromatic Acetals In Water, Ram Mohan, Margaret Olson, James Carolan, Michael Chiodo, Phillip Lazzara

Scholarship

The deprotection of aromatic as well as conjugated acetals and ketals in water is catalyzed by iron(III) tosylate (1.0–5.0 mol %). Iron(III) tosylate is an inexpensive and readily available catalyst. The use of water, the most environmentally benign solvent, makes this procedure especially attractive for acetal deprotection.

Synthesis And Reactivity Of Alpha-Azido Acylals, Gretchen Bell

Honors Theses

alpha-Azido -Azido acylals are a novel combination of azide (N3) and acylal [R-C(OOCR)2] functional groups. Since these compounds are new chemical entities, little is known in the chemical literature about their physical, chemical, and biological properties. This synthetic methodology investigation sought to (1) develop a one-pot, two reaction method for preparing alpha-azido acylals and (2) investigate the chemical reactivity of alpha-azido acylals with phosphine reagents. Progress has been made and will be discussed regarding both the synthesis and reactivity of alpha-azido acylals. This work developed methods and processes that will have significant impact in our broader objective of exploring the …

Langmuir Films Of Flexible Polymers Transferred To Aqueous/Liquid Crystal Interfaces Induce Uniform Azimuthal Alignment Of The Liquid Crystal, Michael I. Kinsinger, Maren E. Buck, Maria Victoria Meli, Nicholas L. Abbott, David M. Lynn

Chemistry: Faculty Publications

We reported recently that amphiphilic polymers can be assembled at interfaces created between aqueous phases and thermotropic liquid crystals (LCs) in ways that: (i) couple the organization of the polymer to the order of the LC and (ii) respond to changes in the properties of aqueous phases that can be characterized as changes in the optical appearance of the LC. This investigation sought to characterize the behavior of aqueous-LC interfaces decorated with uniaxially compressed thin films of polymers transferred by Langmuir-Schaefer (LS) transfer. Here, we report physicochemical characterization of interfaces created between aqueous phases and the thermotropic LC 4-cyano-4′-pentylbiphenyl (5CB) …

The Roles Of Rhle And Hfq In Srna-Dependent Gene Regulation, Abeykoon Jayalath Iresha Sandeepanie Rathnayake

Wayne State University Theses

THE ROLES OF RHLE AND HFQ IN SRNA-DEPENDENT GENE REGULATION

by

ABEYKOON JAYALATH IRESHA SANDEEPANIE RATHNAYAKE

DECEMBER 2010

Advisor: Dr. Andrew Feig

Major: Chemistry

Degree: Master of Science

Bacteria are adapted to live in diverse environmental conditions. Thus, they show excellent tolerance and response to extreme environmental conditions caused by low or high temperatures, high salinity, reactive oxygen species or high nutrient concentrations. sRNAs have been identified and characterized as cis-acting or trans-acting post-transcriptional regulators in diverse cellular processes including virulence and adaptation to environmental stress (11,12,14,15). Interactions of sRNAs and target mRNAs result in translational repression, translational activation or/and …

Stability Of Spore-Based Sensing Systems, Abhishek Sangal

University of Kentucky Master's Theses

The full exploitation of bacterial whole-cell biosensing systems in field applications requires the survival of bacterial cells and long term-preservation of their sensing ability during transportation and on-site storage of such analytical systems. Specifically, there is a need for rapid, simple and inexpensive biosensing systems for monitoring human health and the environment in remote areas which often suffer from harsh atmospheric conditions and inadequate commercial distribution and storage facilities. Our laboratory has previously reported the successful use of bacterial spores as vehicles for the long-term preservation and storage of whole-cell biosensing systems at room temperature.

In the present research, we …

Functionalization Of Multi-Walled Carbon Nanotubes And The Interactions Of Multi-Walled Carbon Nanotubes In Epoxy Composites, Christopher Fitzwater

University of Kentucky Master's Theses

Multi-walled carbon nanotubes (MWNTs) are a relatively new allotrope of carbon that have potentially useful properties that may improve polymer composites. The work of this thesis explores the interactions between MWNTs and functionalized MWNTs within epoxy matrix and the properties of the MWNT/epoxy composite. These interactions were characterized with an emphasis on finding how well the MWNT/epoxy composite flows and how conductive it is after curing.

Synthesis, Characterization And Development Of Catalysts For Co2 Capture, Anitha Suhas Wishrojwar

University of Kentucky Master's Theses

Fossil fuel and advanced industrialization techniques contribute to global warming through emissions of greenhouse gases such as CO₂. In order to mitigate climate change, there is a desperate need to reduce CO₂ emissions from different sources. CO₂ capture and sequestration (CCS) play an important role in these reductions.

Naturally occurring enzymes, e.g., carbonic anhydrase (CA), can catalyze these reactions in living systems. Much effort has been focused on complexes of zinc with ligands such as teta, cyclen and tripodal ligands including BIMA and Trispyrazolylborates. These complexes have many interesting CO₂ capture properties, but maintain toxic …

Solid Supported Synthesis Of Secondary Amines Via Staudinger And Microwave Aza-Wittig Reactions, Kyle Thomas Holsinger

Undergraduate Honors Thesis Collection

Amine bond formation is a major topic in organic chemistry and is widely applied to the formation of medicinal compounds. Current studies have analyzed the benefits of microwave irradiation and solid supported reagents in order to improve reaction conditions and both synthetic and environmental costs. In the synthesis of amines, we investigate the combined use of microwave irradiation and solid supported reagents in the aza-Wittig and reductive amination reaction.

Ohio Conservation Plan: Plains Gartersnake, Thamnophis Radix, Norman Reichenbach, M. Barrie, K. Becka, G. Burghardt, S. Butterworth, C. Caldwell, F. Dierkes, P. Johantgen, K. Stanford, D. Wynn

Faculty Publications and Presentations

This plan outlines strategies and methods used in an ongoing study initiated in 1999 to restore a selfsustaining population of the Plains gartersnake (Thamnophis radix) in Ohio. Restoring a self-sustaining population would require increases in the current population to where the ratios of T. radix to T. sirtalis are approximately 1:1 in multiple locations in Killdeer Plains Wildlife Area (KPWA). This ratio would be similar to what was seen earlier by Reichenbach and Dalrymple (1986) at one site in KPWA.

The plan was developed by a team of enthusiastic conservationists representing, the Division of Wildlife (ODW), the Columbus and Cleveland …

Summary Of Work While A Link Energy Fellow, Michael T. Colvin

Link Foundation Energy Fellowship Reports

Electrons have an intrinsic property called spin, which is found in one of two states, an “up” and a “down”. The spin state of an electron can be observed and differentiated by applying an external magnetic field and inducing transitions with microwaves. The bulk of my graduate work has focused on understanding, controlling, and transferring spin information in molecular systems in the presence of light. If we can understand and transfer spin information it could be used for quantum computing which could revolutionize computing and information processing. This undertaking is difficult and at this point remains largely unexplored in organic …

Analytical Chemistry 2.0, David Harvey

Chemistry & Biochemistry Faculty publications

No abstract provided.

Molecular Structure Of Fac-Aquadichlorotris(Dimethylsulfoxide)Ruthenium(Ii), L. Foster, J. Hardin, Mark Draganjac, B. C. Noll

Journal of the Arkansas Academy of Science

No abstract provided.

Analysis Of The Electron Withdrawing Capability Of Acetylene Groups For Promoting Nucleophilic Aromatic Substitution, Eric D. Braunstein

Honors Theses

It is well known that electron withdrawing groups, such as nitro or carbonyl groups, activate benzene rings for nucleophilic aromatic substitution. However, little research has been done to investigate the electron withdrawing capability of acetylene groups for substitution of aromatic halides. Experimental and computational investigations on the reactivity of halogenated phenylacetylenes with oxygen and other nucleophiles will be described.

Thiol-Ene Chemistry For The Synthesis And Modification Of Branched Organosilicon Polymers, David Son, Christiana Rissing, Li Chen, Theodore Andersson

Chemistry Research

No abstract provided.

Energy Of The Conduction Band In Near Critical Point Fluids, Cherice M. Evans, G. L. Findley

Publications and Research

The study of the evolution of the conduction band in dense gases and supercritical fluids near the critical point has been complicated by a lack of precise experimental measurements. Both photoemission from an electrode immersed in the fluid and field ionization of a molecule doped into the fluid have been used to probe solvent density effects on the energy of an excess electron as a function of fluid number density and temperature. In this perspective, we present recent experimental results that show a strong critical point effect on the minimumconduction band energy near the critical density and temperature of a …

Sampling The Conformation Of Protein Surface Residues For Flexible Protein Docking, Patricia Francis-Lyon, S Gu, J Hass, N Amenta, P Koehl

Nursing and Health Professions Faculty Research and Publications

Background: The problem of determining the physical conformation of a protein dimer, given the structures of the two interacting proteins in their unbound state, is a difficult one. The location of the docking interface is determined largely by geometric complementarity, but finding complementary geometry is complicated by the flexibility of the backbone and side-chains of both proteins. We seek to generate candidates for docking that approximate the bound state well, even in cases where there is backbone and/or side-chain difference from unbound to bound states.

Results: We divide the surfaces of each protein into local patches and describe the effect …

Corrosion Protection Properties Of Various Ligand Modified Organic Inorganic Hybrid Coating On Aa 2024-T3, Rajath Varma, John Cassidy, Mohamed Oubaha, Colette Mcdonagh, John Colreavy, Brendan Duffy

Articles

The inclusion of zirconium precursors to prepare organosilane solgel coatings improves the corrosion protection performance of the coatings on aluminium and steel. The inherent differences in the hydrolysis rates of the silane and zirconium precursors, various ligands were used to control the hydrolysis by decreasing the number of reactive alkoxide group. Hybrid sols were synthesised using 3-(trimethoxysilyl) propylmethacrylate (MAPTMS) and zirconium n-propoxide chelated with organic ligands including different organic acids, acetyl acetone and 2 2’ bipyridyl. The effects of zirconia inclusion on the properties of the coatings were compared on the aerospace alloy AA 2024-T3. Electrochemical analysis and salt spray …

Rapid Microwave Synthesis Of Mesoporous Tio2 For Electrochromic Displays, Suresh Pillai, Declan Mccormack, Pradeepan Periyat, Nigel Leyland, David Corr, John Colreavy

Articles

No abstract provided.

Geochemical Investigation Of An Offshore Sewage Sludge Deposit, Barcelona, Catalonia, Spain, Michael A. Kruge, Albert Permanyer, Jordi Serra, Danlin Yu

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

For 20 years ending in the 1990’s the city of Barcelona discharged the products from a large primary sewage treatment plant directly into the Mediterranean Sea via underwater conduits. About ca. 3 million m³ of relict sewage sludge, rich in organic matter and heavy metals, has spread over an elongated area offshore, due to successive ruptures of the conduits. The use of the discharge pipes ceased, but he sludge deposit remains in place for the time being.

To understand the history and present state of the sludge deposit in advance of future remediation, a program of geophysical mapping, sampling, …

Synthesis And Uses Of Polycarbonate, Hai Bui

Natural Sciences Student Research Presentations

Polycarbonate is one of the most important polymers being used today. Polycarbonate has many important characteristics that prove to be useful in its applications. Some characteristics of polycarbonate are that it is clear, light weight, and durable. The optical properties and the specific weight index of polycarbonate make it ideal for lens material in eyeglasses. There are two main ways of commercially synthesizing polycarbonate from bisphenol A. It can be synthesized through the process of solvent interfacial polymerization or through melt transeterification. Both processes are different and each has its own benefits.

2-(9-Anthrylmethyl­­Idene­Amino)-4-Methyl­Phenol, Ralph Isovitsch

Chemistry

The title compound, C22H17NO, is a novel Schiff base synthesized via a condensation reaction between 9-anthracenecarboxaldehyde and 2-amino-p-cresol. The asymmetric unit contains two independent mol­ecules that are joined by an O—H⋯OH hydrogen bond. An intra­molecular O—H⋯N hydrogen bond occurs in each mol­ecule. π-stacking about inversion centers was observed between adjacent phenol rings [centroid–centroid distance = 3.850 (2) Å] and adjacent anthracene rings [centroid–centroid distance = 3.834 (2) Å]. The C—N=C—C torsion angles between the phenol and anthracene rings are close to 180° with values of 174.06 (15) and 179.85 (14)°.

The Synthesis, Photophysical Characterization, And X‐Ray Structure Analysis Of Two Polymorphs Of 4,4′‐Diacetylstilbene, Ralph Isovitsch, Cameron Pye, Frank R. Fronczek

Chemistry

A palladium(II) acetate‐catalyzed synthesis of 1 that utilizes the novel triazene 1‐{4‐[(E)‐morpholin‐4‐yldiazenyl]phenyl}ethanone as a synthon is described. The room temperature absorption spectra of 1 in various solvents exhibited a π→π* transition in the range of 330–350 nm. Compound 1 was observed to be luminescent, with room‐temperature solution and solid‐state emission spectra that exhibited maxima in the range 400–500 nm. All room‐temperature absorption and emission spectra exhibited some degree of vibrational structure. The emission spectrum of 1 at 77 K in propanenitrile glass was broad and featureless with a maximum at 447 nm. Compound 1 crystallized …

Resin-Modified Glass-Ionomer Setting Reaction Competition, David W. Berzins, S. Abey, M. C. Costache, Charles A. Wilkie, H. W. Roberts

Chemistry Faculty Research and Publications

Resin-modified glass ionomers (RMGI) set by at least 2 mechanisms dependent upon reactant diffusion prior to gelation. Each reaction’s kinetics and setting mechanism may rely on and/or compete with the other. In this study, we investigated RMGI setting reaction interactions using differential scanning calorimetry (DSC) by varying light-cure initiation times. A RMGI was analyzed with isothermal and dynamic temperature scan DSC with light-curing occurring immediately, or at 5 or 10 minutes after mixing as well as without light-activation. Results show that as time allowed for the acid-base reaction increased, the light-activation polymerization exotherm decreased. Conversely, analysis of DSC data suggests …

Substrate Specificity And Kinetic Studies Of Pads 1, 3, And 4 Identify Potent And Selective Inhibitors Of Protein Arginine Deiminase 3, Bryan Knuckley, Corey P. Causey, Justin E. Jones, Monica Bhatia, Christina J. Dreyton, Tanesha C. Osborne, Hidenari Takahara, Paul R. Thompson

Tanesha C. Osborne

Protein citrullination has been shown to regulate numerous physiological pathways (e.g., the innate immune response and gene transcription) and is, when dysregulated, known to be associated with numerous human diseases, including cancer, rheumatoid arthritis, and multiple sclerosis. This modification, also termed deimination, is catalyzed by a group of enzymes called the protein arginine deiminases (PADs). In mammals, there are five PAD family members (i.e., PADs 1, 2, 3, 4, and 6) that exhibit tissue-specific expression patterns and vary in their subcellular localization. The kinetic characterization of PAD4 was recently reported, and these efforts guided the development of the two most …

A Chloroacetamidine-Based Inactivator Of Protein Arginine Methyltransferase 1: Design, Synthesis, And In Vitro And In Vivo Evaluation, Obiamaka Obianyo, Corey P. Causey, Tanesha C. Osborne, Justin E. Jones, Young-Ho Lee, Michael R. Stallcup, Paul R. Thompson

Tanesha C. Osborne

Protein arginine methyltransferases (PRMTs) catalyze the post-translational methylation of arginine residues. PRMT1 is the predominant mammalian isozyme, and is responsible for generating the majority of the asymmetrically dimethylated arginine found in vivo. The dysregulation of this enzyme has been implicated in heart disease and cancer; thus, its inhibition would be useful in the treatment of these diseases. Herein, we describe the most potent PRMT1 inhibitor described to date. This compound, denoted C21, is a chloroacetamidine-containing peptide that is able to irreversibly bind and inactivate the enzyme selectively. We have also shown that the coactivator activity of PRMT1 is selectively inhibited …

Platinum And Palladium Complexes Containing Cationic Ligands As Catalysts For Arene Hid Exchange And Oxidation., J. Brannon Gary

Faculty Publications

The direct functionalization of CH bonds has frequently been deemed a “Holy Grail” of organometallic chemistry.[1] A seminal example of this transformation was the demonstration by Shilov and co-workers that platinum(II) salts catalyze the direct oxidation of alkanes into their corresponding alcohols and alkyl halides.[2] Subsequent work in this area has focused on surveying diverse ligands for these reactions in an effort to enhance reactivity and selectivity, slow catalyst decomposition, and replace platinum(IV)-based oxidants with more cost-effective alternatives.[3–5] In a key development, chemists at Catalytica identified [bpymPtCl2] (bpym = bipyrimidine) as a pre-catalyst for the oxidation of CH4 into CH3OSO3H …

Biointeraction Analysis By High-Performance Affinity Chromatography: Kinetic Studies Of Immobilized Antibodies, Mary Anne Nelson, Annette C. Moser, David S. Hage

David Hage Publications

A system based on high-performance affinity chromatography was developed for characterizing the binding, elution and regeneration kinetics of immobilized antibodies and immunoaffinity supports. This information was provided by using a combination of frontal analysis, split-peak analysis and peak decay analysis to determine the rate constants for antibody–antigen interactions under typical sample application and elution conditions. This technique was tested using immunoaffinity supports that contained monoclonal antibodies for 2,4-dichlorophenoxyacetic acid (2,4-D). Association equilibrium constants measured by frontal analysis for 2,4-D and related compounds with the immobilized antibodies were 1.7–12 × 10⁶ M⁻¹ at pH 7.0 and 25 °C. Splitpeak …

A General Approach For Receptor And Antibody-Targeted Detection Of Native Proteins Utilizing Split-Luciferase Reassembly, Cliff I. Stains, Jennifer L. Furman, Jason R. Porter, Srivats Rajagopal, Richard T. Wyatt, Indraneel Ghosh

Cliff Stains Publications

The direct detection of native proteins in heterogeneous solutions remains a challenging problem. Standard methodologies rely on a separation step to circumvent nonspecific signal generation. We hypothesized that a simple and general method for the detection of native proteins in solution could be achieved through ternary complexation, where the conditional signal generation afforded by split-protein reporters could be married to the specificity afforded by either native receptors or specific antibodies. Toward this goal, we describe a solution phase split-luciferase assay for native protein detection, where we fused fragmented halves of firefly luciferase to separate receptor fragments or single-chain antibodies, allowing …

Ni Doping Of Semiconducting Boron Carbide, Nina Hong, Marjorie Langell, Jing Liu, Orhan Kizilkaya, Shireen Adenwalla

Marjorie A. Langell Publications

The wide band gap, temperature stability, high resistivity, and robustness of semiconducting boron carbide make it an attractive material for device applications. Undoped boron carbide is p type; Ni acts as a n-type dopant. Here we present the results of controlled doping of boron carbide with Ni on thin film samples grown using plasma enhanced chemical vapor deposition. The change in the dopant concentration within the thin film as a function of the dopant flow rate in the precursor gas mixture was confirmed by x-ray photoelectron spectroscopy measurements; with increasing dopant concentration, current-voltage (I-V) curves clearly establish the trend from …