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Simple Descriptors For Modeling The Solubility Of Gases, Alcohols, And Halogenated Hydrocarbons In Water, Sule Sidigu
Simple Descriptors For Modeling The Solubility Of Gases, Alcohols, And Halogenated Hydrocarbons In Water, Sule Sidigu
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The Statmost, QSARIS, Excel, and SAS programs were used to model the solubility of gases, alcohols, and halogenated hydrocarbons in water using simple physical and topological descriptors. The alcohols were well-modeled using measures of the number of carbons, terminal methyls, and steric hindrance about the hydroxyl group. Molecular mass, boiling point, and critical volume or critical pressure were the best descriptors for the halogenated hydrocarbons. Critical pressure was the most applicable single descriptor for the gases. Molecular mass and boiling point also yielded good results for the gases and halogenated hydrocarbons when regressed together.
The Electroanalytical Performance Of Sonogel Carbon Titanium (Iv) Oxide Electrodes Versus Conducting Polymer Electrodes In The Electrochemical Detection Of Biological Molecules, Jelynn A. Stinson
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The electrochemical performance of a newly developed sonogel carbon titanium (IV) oxide (SGC/TiO2 ) electrode against poly(3-methylthiophene) (P3MT) and poly(2,2'-bithiophene) (PBTP) modified electrodes in the electrochemical detection of biological molecules is reported. The stability of the Titanium (IV) Oxide coating on the sonogel carbon electrode was shown to be greater than the P3MT coating on the conventional size glassy carbon electrode. After 10 consecutive scans, there was a 21% loss of the initial signal at the P3MT modified electrode and a 5% loss of the initial signal at the SGC/TiO2 electrode. The influence of NAD+ on NADH response was tested. …
Laser Initiated Chain Reactions: The Kinetics Of The Chlorine/Cyclohexane/Oxygen Chain System, Robert Alan Forlines
Laser Initiated Chain Reactions: The Kinetics Of The Chlorine/Cyclohexane/Oxygen Chain System, Robert Alan Forlines
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The combination of laser photolysis with infrared chemiluminescence detection has proven an effective technique for determining the propagation rate coefficients of halogen + RH chain reactions. This thesis will extend the technique to cyclic alkanes by determining the propagation rate coefficients of the Cl2/ cyclohexane chain system as well as the rate coefficient for the primary chain termination mechanism, R + O2 → RO2. The following reaction scheme is supported by the kinetic analysis: Cl2 → 2Cl Laser Photolysis Cl + RH → HCl(v) + R First Propagation Step (k1) R + …
Synthetic Approach To Epibatidine From 1-(Phenylsulfonyl)Pyrrole, Brandon G. Vanness
Synthetic Approach To Epibatidine From 1-(Phenylsulfonyl)Pyrrole, Brandon G. Vanness
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The goal of this research was to synthesize the natural product epibatidine, a non-opiate analgesic and nicotinic acetylcholine agonist isolated from Epipedobates tricolor. A synthetic pathway utilizing a Diels-Alder cycloaddition of a 3-pyridyl substituted pyrrole and tosylacetylene was conceived based upon the original mass spectral fragmentation pathway of epibatidine determined by Daly. Although this pathway had been previously attempted using 1-(triisopropyl)-3-[5-(2-chloropyridyl)]pyrrole in the key Diels-Alder step, the lack of cycloadduct suggested that a pyrrole with a more electron withdrawing protecting group was required for this step. Therefore, synthesis of 1-(phenylsulfonyl)-3-[5-(2-chloropyridyl)]pyrrole via a palladium catalyzed cross-coupling reaction of 1-(phenylsulfonyl)-3-pyrroline and …
Synthesis And Electrical Properties Of Fluorenyl Polyesters Incorporating Diamond Fragments, Kevin John Wiacek
Synthesis And Electrical Properties Of Fluorenyl Polyesters Incorporating Diamond Fragments, Kevin John Wiacek
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Based on the paradigm of diamond as a wide band-gap electrical insulator, molecular counterparts to crystalline diamond (cyclohexane, adamantane, and diamantane) were incorporated into a high-temperature fluorenyl polyester (FPE) with the intent of increasing the breakdown strength. The effect of incorporating a CycloteneTM thermoset as a crosslinking agent to increase the dielectric strength and the self-healing phenomena of these polymers were also investigated. Polymers were synthesized using 9,9-bis(4-hydroxyphenyl)fluorene and the diacid chloride of cyclohexane, adamantane, and diamantane. Thin films of the polymers were cast from chloroform and the electrical properties were investigated. The polyester incorporating the largest diamond fragment had …
Synthetic Routes To A Fused-Ring Sydnoquinazoline, Gregory Edmond Storer
Synthetic Routes To A Fused-Ring Sydnoquinazoline, Gregory Edmond Storer
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In this research, 5-methylsydno-[3,4-a]quinazoline was synthesized via multiple methodologies, the best of which yielded the target compound in 50 % overall yield for the six steps. Synthesis of this compound in reasonable yields and exploration of its chemical behavior is of particular interest as a putative NO-prodrug. As an initial approach to the synthesis and accumulation of the compound of interest, attempts were made to optimize the existing synthetic pathway to its precursors. The starting material, 3-(2-acetylphenyl)sydnone, was prepared in 3 steps from commercially available starting material in good yields. This sydnone compound was then converted to the versatile intermediate, …
Modifiable Poly(Arylene Ether)S And Hyperbranched Poly(Esters), Brian Scott Werry
Modifiable Poly(Arylene Ether)S And Hyperbranched Poly(Esters), Brian Scott Werry
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Two different polymer systems have been studied in regards to their potential for functionalization to introduce new characteristics to the polymer. The first polymer system is a poly(arylene ether) with a truly pendant sulfone group from the monomer 3,5-difluorodiphenylsulfone. The work entails incorporating a bromine moiety onto the monomer for the versatile ability to bring in functional groups prior to or post the polymerization. The introduction of bromine onto the pendant ring had the best results from electrophilic bromine addition using N-bromosuccinimide in a mixture of sulfuric acid and acetic acid (80:20) yielding 76% of the desired material. Incorporation of …
Laser Induced Fluorescence Spectroscopy Of Molecular Bromine: Observations Of Emission To High Vibrational Levels In The Ground (X) State, David Jonathan Postell
Laser Induced Fluorescence Spectroscopy Of Molecular Bromine: Observations Of Emission To High Vibrational Levels In The Ground (X) State, David Jonathan Postell
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The Laser Induced Fluorescence spectrum of the B - X system of molecular bromine was recorded using a Red and Near Infrared sensitive PMT coupled to a scanning monochromator. A 543 nm HeNe laser was used to excite three resonances. Assignment of those resonances was made. A line narrowed Nd:YAG laser was used to excite eight fluorescence progressions, six from the (79,81) bromine isotopomer and one each from the (79,79) bromine and (81,81) bromine isotopomers. Analysis of the visible bands helped determine the resonances excited by the Nd:YAG laser. Fluorescence in the near infrared region, 9500 - 14000 angstroms, was …
Hydrophobically Modified Polyethyleneimines And Ethoxylated Polyethyleneimines, Michael Joseph Simons
Hydrophobically Modified Polyethyleneimines And Ethoxylated Polyethyleneimines, Michael Joseph Simons
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The modification of the commercially available polymers polyethyleneimines and ethoxylated polyethyleneimines took place with approximately a 3-10% alkylbromide modification followed by, in the case of the polyethyleneimines, a 2-hydroxypropyl modification, using propylene oxide, on the order of 65-70%. The objective was to increase the hydrophobicity of the polymer while keeping the cloud point above 60°C. Another approach taken was to form hydrophobic ethers from ethoxylated polyethyleneimine. We also added a 2-hydroxy ethyl group to a hexylated polyethyleneimine avoiding the use of ethylene oxide or drying EPI.
Tailoring Branching For Poly (Arylene Ether)S Via Reactivity Ratio Controlled Polymerizations, Amanda Ike
Tailoring Branching For Poly (Arylene Ether)S Via Reactivity Ratio Controlled Polymerizations, Amanda Ike
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The ability to control physical and mechanical properties of polymer systems has become an important aspect of polymer science. In order to tailor the branching in polymer systems, an understanding into the reactivity of the electrophilic sites in the monomer is important. Kinetic methods have been explored in order to determine the reactivity of monomers in preparing poly(arylene ether)s and to predict the degree of branching that will occur in a polymer of this kind. The reactivity of AB2 sulfones and phosphine oxides was explored, along with the reactivity of ABB'B'' sulfones. NMR spectroscopy was used as a probe into …
Preparation And Derivatization Of Novel Sydnonimines And Their Esters, Timothy Luke Teschler
Preparation And Derivatization Of Novel Sydnonimines And Their Esters, Timothy Luke Teschler
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Some years ago, we reported that 3-phenylsydnone underwent dilithiation to yield the dilithio species, upon treatment with n-butyllithium. Subsequent reactions with electrophiles led to variously substituted aryl sydnones, dependent on the nature of the electrophile employed. Sydnonimines, exocyclic nitrogen analogs of sydnones, exhibit interesting biological properties and, accordingly, it was of value to explore whether or not the dilithiation approach could be extended to such species. In the present work a series of N-6-ethoxycarbonyl-3-arylsydnonimines were synthesized from the corresponding sydnonimine hydrochlorides in moderate yields (22-77%). Attempted dilithiations of N-6-ethoxycarbonyl-3-arylsydnonimines and trapping with iodine proved to be problematic, yielding only the …
Formation Of A Sydno[3,4- A]Indolone And Reactions Thereof, Ryan Christopher Vikan
Formation Of A Sydno[3,4- A]Indolone And Reactions Thereof, Ryan Christopher Vikan
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In the present work, a synthetic route to the formation of a sydno[3,4- a]indolone was explored in the hope of attaining the first example of a fused-ring sydnone with an sp2-hybridized bridge. Formation of this product and exploration of its chemical behavior was anticipated to be of particular interest to the formation of NO-releasing prodrugs. A direct synthetic pathway to yield the target sydnoindolone starting from 3-(2-methoxycarbonylphenyl)sydnone and reaction with a base was proposed and explored. Attempted formation and isolation of the target sydnoindolone proved impossible under a variety of different conditions, undoubtedly due to the instability of this …