Chemistry Commons^™

Kinetics Of The Metal-Exchange Reaction Between N-(2-Pyridylmethyl)Iminodiacetatonickel(N) And Copper(Ii), Kassahun W. Beyene

Masters Theses

The reaction between N-(2-pyridylmethyl)iminodiacetatonickel(II) and copper(II) was studied spectrophotometrically between pH 2.30 and 3.30 over a 10-fold variation in copper concentration at an ionic strength of 1.25M, and a temperature of 25.0+0.1^oC. The reaction is first order in both NiPyIDA and copper(II). Terms involving proton attack and a copper dependent dissociation of the nickel complex were resolved from the data. Evidence is given for a stepwise unwrapping mechanism PyIDA from the nickel complex, followed by copper attack to give a dinuclear intermediate. A general mechanism is presented which is consistent with the kinetic data.

Comparisons to analogous nickel-aliphatic …

Effect Of Polymerization Conversion On The Experimental Determination Of Monomer Reactivity Ratios In Copolymerization, Sevim Zeynep Erhan

Dissertations

In this study the comparison of the methods used to calculate monomer reactivity ratios from experimental copolymer composition data is targeted.

For this purpose, nine samples of each of nine different concentrations of styrene-methyl methacrylate monomer mixtures were prepared. These mixtures were then polymerized for different times ranging from one to nine hours and the percent conversion to copolymer was determined.

The compositions of these copolymers were determined by their refractive index increments measured in two different solvents. Ultraviolet absorption spectroscopy was also studied as a possible method to find copolymer compositions. Though this method has been used previously, UV …

Investigation Of The Synthesis And Polymerization Behavior Of Vinyl Benzoate, Selim Mehmet Erhan

Dissertations

The goal of this study is to present a method that gives higher conversions and molecular weights for the polymerization of vinyl benzoate than obtained in previous investigations.

Polyvinyl benzoate has benzene rings attached to the backbone chain, therefore is hard and rigid. This is a characteristic which has a large application area. However previous studies in polymerizing vinyl benzoate with bulk and solution polymerizations reported low yields and troublesome crosslinking, which has limited its application. Emulsion polymerization method has the advantage of giving high polymerization rates together with high molecular weights, and therefore was chosen as the method for …

Investigation Of Complex Formation By Oligomers Of Cytosine And Guanosine, Steven Roberts Davis

Chemistry & Biochemistry Theses & Dissertations

Duplex formation between oligo(C:G) _n where n=3 to 4 was shown not to occur under conditions favorable for duplex formation between poly G and poly C. Instead, a stable guano sine self-structure was found to form which a T_m of 50°C for (Gp)₃ and 80°C for (Gp)₄ at strand concentrations of 10^-5M in 1M NaCl. Neither a duplex nor a self-structure formed in the absence of salt.

Oligomers of guanosine and cytosine were obtained by basic hydrolysis and separated according to chain length using DEAE Sephadex column chromatography. Separation of cytosine oligomers with chain lengths …

Gas Permeation Measurements On Small Polymer Specimens, Karen S. Burns

Chemistry & Biochemistry Theses & Dissertations

Mass spectrometry was used to measure oxygen and nitrogen permeabilities while polarography was used to measure oxygen permeabilities for several contact lens materials. Applicable sample holders were designed and fabricated to accommodate curved and flat specimens with surface areas of 0.5 cm² and 1.0 cm² and thicknesses between 0.025 mm and 0.500 mm. A prepared standard was used to calibrate the mass spectrometric analyses.

The oxygen permeability values determined by mass spectrometry were significantly greater than those determined by polarography. This was attributed to the phase boundary phenomena and the limiting oxygen permeance of water inherent in the …

Synthesis Of Potential Long Acting Calcium Channel Antagonists: A Study Of 1,4-Dihydropyridine Analogs, Thomas E. Christos

Chemistry & Biochemistry Theses & Dissertations

An investigation was undertaken to synthesize and evaluate longer acting analogs to the antihypertensive agent nifedipine. Analogs that are capable of covalent bonding to the nifedipine receptor were considered. These compounds may show increased activity as they will remain at the receptor for a longer period of time.

During the course of this study, previously unreported and unexpected products were encountered and lead to a more intense examination of the Hantzsch synthesis. Of particular interest was the oxazolidine 25 which was a major component of the Hantzsch synthesis when ethanolamine was used instead of ammonium hydroxide. Also isolated during this …

Reactions Of Organic N-Chloramines In The Gastric Fluid Of The Rat, Kathryn E. Mazina

Chemistry & Biochemistry Theses & Dissertations

Using chlorine as a drinking water disinfectant may have potential health effects due to its reactivity with organic amino nitrogen compounds found in the stomach. Organic N-chloramines have been shown to form in the stomachs of laboratory rats. The possible reactions of N-chloramines in the stomach fluid were examined in this study using a model radiolabeled N-chloramine. ³⁶Cl-N-Chloropiperidine, was synthesized and purified to remove ³⁶Cl-chloride. Stomach fluid was obtained from Sprague-Dawley rats which had been first fasted for 24 or 48 hours and then administered 3 mL of deionized water. Different concentrations of radiolabeled chloramine were reacted with …

Determination Of Amino Acids And Chloramino Acids In Municipal Wastewater, Jeffrey Taylor Jewell

Chemistry & Biochemistry Theses & Dissertations

It is well known that unchlorinated municipal wastewater contains high levels of organic and inorganic amino nitrogen compounds, the single most abundant amino-N species being ammonia. Upon chlorination, these compounds are transformed almost instantaneously and quantitatively into N-chloramino derivatives. The organic chloramines have been shown to

interfere with disinfection and have lower disinfection capacities than their inorganic counterpart monochloramine. The environmental effects imposed by the discharge of these compounds into natural receiving waters is unknown. This study has shown that amino acid precursors for N-chloramino acids range in concentration from 1.4 X 10^-7 M to 9.0 X 10^{-7 …}

Fluoride As A Therapeutic Drug In Osteoporosis Treatment, Rita Priyadarshani Francis

Honors Theses

The use of fluoride as a therapeutic drug is not a novel idea. Studies dealing with the effects of fluoride on the skeletal system date back to the late 1960's. This paper will define osteoporosis, examine methods of detection, and will discuss various methods of treatment with emphasis on the use of fluoride supplements in the form of tablets or fluorinated drinking water.

The Use Of Direct Current Argon Plasma Spectroscopy For Quantitative Analysis Of Geological Samples, Stephen N. Lipsky

Honors Theses

The focus of this project was the development of a process of analyzing geological samples which contain moderate amounts of silica. The main emphasis was put upon the reduction of the amount of "wet" chemistry and laboratory time involved in such analysis. Previous elemental analysis of such samples relied upon time consuming techniques such as combustion and precipitation reactions. Moreover, these analyses required the use of highly corrosive hydrofluoric acid (HF). This project utilized a DC Argon Plasma Spectrometer (DCP) for all elemental analyses. Furthermore, the only chemical required for the project was concentrated nitric acid. This project proposed that …

Synthesis Of 3, 6-Dimethyl-9, 10-Bis (Trimethylsilyl) Diimine: Structural Modification Of An Electrically Conductive Organic Solid, Cynthia A. Morphet

Honors Theses

The current, intense interest in non-classical electrical conductivity and superconductivity has stimulated an equally intense effort to synthesize new materials which exhibit enhanced electrical conductivities. This thesis reports such an effort. Previous work had resulted in the formation of planar aromatic compounds capable of acting as "synthetic metals", i.e.: of conducting an electrical charge. These efforts had focused on compounds utilizing heteroatoms from Group VIA. Efforts to synthesize analogous compounds utilizing heteroatoms from Group VA had been partially successful, but were hampered by solubility considerations. This research focuses on the synthetic procedure developed to produce an analog of one of …

Spectral Studies Of Pyrene Carboxylic Acids, Jeannie Haller

Honors Theses

The pKa and pKa* of 1-pyrenecarboxylic acid (PCA) in a 50% ethanol/water solvent were experimentally (letermined to be 4.3 and 5.2, respectively. The pK8 of pyrene acrylic acid (PAA) in the same solvent was experimentally determined to be 4.6. An excited state equilibrium was not reached at the buffer concentrations used for the pKa* analysis; therefore, a valid value for the pKa* can not be reported at this time, but taking both the experimental results and the calculated pK8.'s into account, it appears that the pKa* of PAA is in the range 6.6 < pKa* < 7.4. The fluorescence of PCA, PAA, and 1-anthroic acid (1-AA) were studied as a function of solvent. The fluorescence of PCA was solvent independent- small spectral shifts as well as the retention of structure were observed in solvents of varying polarity. The fluorescence of 1-AA and PAA exhibited a solvent dependence. The results of both the pKa analysis and the fluorescence studies indicate that the S0 and the S1 states of PCA have a similar geometry, but that the geometry of the S0 and the S1 states of PAA differ. The change in geometry may be the rotation of the carboxyl group from its nearly perpendicular position with the ring in the S0 state to a more coplanar position with the ring in the S1 state. The effects of hydrogen bonding in hexafluoroisopropanol on the spectral properties of PAA were studied, and the results of the studies indicate that PAA forms a hydrogen-bonded complex with hexafluoroisopropanol in both the ground and the excited states.

Determination Of The Kinetic And Thermodynamic Properties For Bisulfite Addition To: Acetophenone, 2-Chloroacetophenone And Trans-Cinnamaldehyde, Laurie Ann Le Tarte

Honors Theses

The equilibrium constants for bisulfite addition to acetophenone, 2-choloroacetophenone and trans-cinnamaldehyde were determined using an ultraviolet spectrophotometric method. The absorbance of the carbonyl compound was monitored as aliquots of a bisulfite solution were added to the reaction cell. By plotting 1/A versus [HSO3-], and dividing the slope by the intercept, it was possible to determine Keq. All determinations were made at pH 4.66 and ionic strength 1.0. By determining Keq at various temperatures it was also possible to determine ΔH° and ΔS°. The equilibrium constants for bisulfite addition to: acetophenone, 2-choloracetophenone and trans-cinnamaldehyde, were determined to be: 5.8 M-1, 53 …

The Synthesis Of Homoallylic Alcohols Through Diasteriomeric Transition States, Jeffrey Lee Osofsky

Honors Theses

Theoretically, optically active homoallylic alcohols can be synthesized by reacting an optically active organotin with an aldehyde in the presence of a Lewis acid. It is expected that the chirality of the organotin will induce one diastereomeric transition state which will have a significantly reduced activation energy than the transition state of the other diastereomer. If the difference between the two activation energies is substantial enough, the transition state with the lower activation energy will be preferred over the other transition state. If the preference is absolute one completely pure alcohol enantiomer will be produced. If there is a preference, …

Making A Rainbow Workstation For A Chemistry Lab, John D. Bak

Honors Theses

Chemical kinetics is the study of how quickly and by what means chemical reactions proceed. Some reactions are so fast and complicated that data must be taken very quickly and then lengthy calculations must be done to get results. Computers speed these studies greatly. The system to he described uses a DEC-Rainbow microcomputer as a terminal for a workstation. The system may collect 8k of buffered data at a rate of 1MHz and then upload the data to a VAX for analysis using the same Rainbow u a graphics terminal. The program for data analysis, called KinSim, will then accept …

Chirality Transfer In The Synthesis Of Homoallylic Alcohols, Simon Paul Drew

Honors Theses

Previous studies on the reaction of the optically active organotin, diallylisopropylmyrtanyltin, to produce homoallylic alcohols, using boron trifluoride as a Lewis acid, produced racemic mixtures regardless of the aldehyde used.1 In this experiment bromine was attached to the tin atom in allylmyrtanylphenyltin bromide, letting tin become an internal Lewis acid. Benzaldehyde was reacted with this compound to see it a single optically active product could be synthesized. After the alcohol had been separated out using vacuum distillation, the optical rotation of the product was taken and showed no appreciable rotation; thus a racemic mixture was produced.

Determination Of The Kinetic And Thermodynamic Properties For Bisulfite Addition To: Acetophenone, 2-Chloroacetophenone And Trans-Cinnamaldehyde, Laurie Ann Letarte

Honors Theses

The equilibrium constants for bisulfite addition to acetophenone, 2-choloroacetophenone and trans-cinnamaldehyde were determined using an ultraviolet spectrophotometric method. The absorbance of the carbonyl compound was monitored as aliquots of a bisulfite solution were added to the reaction cell. By plotting 1/A versus [HSO3-], and dividing the slope by the intercept, it was possible to determine Keq. All determinations were made at pH 4.66 and ionic strength 1.0. By determining Keq at various temperatures it was also possible to determine ΔH° and ΔS°. The equilibrium constants for bisulfite addition to: acetophenone, 2-choloracetophenone and trans-cinnamaldehyde, were determined to be: 5.8 M-1, 53 …

Equilibrium Constant Determination For Bisulfite Addition To Aromatic Aldehydes, Daniel Y. Choi

Honors Theses

Equilibrium constants for bisulfite addition to benzaldehyde and its derivatives were determined by a spectrophotometric method developed by Kokesh and Hall. The concentration of the benzaldehyde derivative was monitored by UV as aliquots of a bisulfite solution are added to a buffered solution of the aldehyde. Additional data on ΔH° and ΔS° for the reactions were derived from the temperature variation of the equilibrium constants. For benzaldehyde, the reaction had an equilibrium constant at 25°C of 6.2 x 103 M-1, a ΔH° of -54.3 kJ/mol, and a ΔS° of -111 J/Mol·K. o-Tolualdehyde exhibited a lower Keq of 2.4 x 103 …

The Synthesis Of Homoallylic Alcohols Through Diasteriomeric Transition States, Jeffrey Lee Osofsky

Honors Theses

Theoretically, optically active homoallylic alcohols can be synthesized by reacting an optically active organotin with an aldehyde in the presence of a Lewis acid. It is expected that the chirality of the organotin will induce one diastereomeric transition state which will have a significantly reduced activation energy than the transition state of the other diastereomer. If the difference between the two activation energies is substantial enough, the transition state with the lower activation energy will be preferred over the other transition state. If the preference is absolute one completely pure alcohol enantiomer will be produced. If there is a preference, …

Direct Coal Liquefaction Using Bis(Dihydrobis(1-Pyrazolyl)Borate)Nickel (Ii) As A Catalyst, Pong Kau Yuen

Theses (Pre-2016)

The direct coal liquefaction of Illinois Number Six River King coal using bis(dihydrobis(l-pyrazolyl)borate)nickel (II) as a catalyst in SRC II (a distillate at 240-450°C) was evaluated at times of 15 minutes. Each run was carried out in a 300 ml magnedrive autoclave reactor under an initial hydrogen pressure of 900-1200 psig and/or at 425-475°C. In case of different hydrogen pressures, the tetrahydrofuran (THF) and cyclohexane conversions increased with increased hydrogen pressure. At the two temperatures of 425°C and 475°C the cyclohexane conversion increased with the increased temperature but the THF conversion decreased. The effects of different solvents and heating-rate of …

Rise To Power Of Senator Joseph R. Mccarthy: Reflections Of The Cold War Mccarthy Era In American Film, Scott Lainer

Honors Theses

The common bond between much of the film industry and Joseph McCarthy was insecurity and the drive for national approval. If one grasps the specific characteristics of McCarthy the man, and the methods of these politically "inspired" movies, we can to better place the period into context and acknowledge the fact that, if the citizenry is not aware, and is again caught by an ever-building wave of trickle down sentiment, the 1950s might not prove to be an isolated period in American history. Insecurity was not a fifties novelty. It still exists, and could potentially escalate anti-Communist policy and sentiment …

Synthetic Studies Toward B-Alkylthiolanthionines, Hwa-Ok Kim

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Synthetic routes toward a B-alkylthiolanthionine derivative, as found in the quinomycin depsipeptide antibiotics, have been studied through a sequence involving as the key intermediates and steps (a) (S) - Z-[(benzyloxycarbonyl)amino]-3,3-dimethoxy-l-propanol (2), prepared from N-benzyloxycarbonyl-L-serine in 3 or 4 steps, (b) N-benzyloxycarbonyl- 0 - tetrahydropyranyl-B,B-(ethylsulfinylethylthio)-alaninol (4a), converted from 2, and (c) attempted Lewis acid catalyzed replacement of alkylsulfinyl function by thiol moiety of cysteine, which gave undesired products. Stability of protecting groups used in this study, which are N,0-isopropylidenyl and tetrahydropyranyl functions in N-protected-L-serinol 20 or 26, under acidic conditions was found to play an important role in determining the optical …

The Preparation And Reaction Of Novel Glycosyl Ureas And Thioureas, Robert Scott Johnson

Masters Theses

No abstract provided.

Studies Of Radiation Effects In Three High Polymers, Heidi Rene-Mitchell Ries

Physics Theses & Dissertations

Three high polymers, Mylar®, Ultem®, and Kapton®, were irradiated to total doses of 1, 5, and 9.5 gigarad using 1-MeV electrons. The glass transition temperatures (T_g) of the materials before and after irradiation were measured using an AC electrical dissipation factor technique. From the T_g data, it was found that the electron radiation at these total doses results in net chain scissioning in Mylar and net crosslinking in Ultem, while self-mending is predominant in Kapton. The dielectric constant was measured before and after irradiation, but no significant changes due to irradiation were observed. Electron paramagnetic resonance (EPR) …

Molecular Properties Of Cetiedil And Its Interactions With Human Erythrocytes, Chakravarthy Narasimhan

Dissertations

No abstract provided.

Synthesis And Characterization Of Some Sf₅- Containing Sulfonic Acids, Robert J. Willenbring

Dissertations and Theses

Pentafluorosulfur (VI) bromide (SF₅Br) adds to olefins of the form CX₂=CX₂, where X= H or F, with the pentafluorosulfur group usually adding to the carbon with more hydrogens attached to it. This series of compounds was used in an attempt to prepare the corresponding sulfonic acid hydrates of the general formula SF₅CX₂CX₂SO₃H·nH₂O, in order to have these compounds tested as possible fuel cell electrolytes. The reaction scheme involved reflux of the SF₅Br adduct with an equimolar amount of sodium sulfite in 50% …

The Synthesis Of 2-Aryl-3-Fluoroalkoxy-1-Propenes And Some Potentially Useful Reaction Of These Systems, Joan E. Brown

Retrospective Theses and Dissertations

This report discusses research involving the fluoroalkoxylation of 2-arylprop-1-en-3-yltrimethylammonium iodides and the useful synthetic application of the adducts formed. The present work includes: 1) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with the sodium salt of 2,2,2-trifluoroethanol; 2) reactions of several fluoroalkoxy alcohols with 2-(4-bromophenyl)prop-1-en-3-yltrimethylammonium iodide; and 3) the oxidation of 2-(4-chlorophenyl)-3-(2,2,2-trifluoroethyoxy)-1-propene using the Lemieux/von Rudloff reagent. This report reveals the experimental conditions and procedures used as well as spectral and physical data of all new compounds synthesized. Explanation is offered for a possible mechanism for the formation of these compounds and recommendations for future research are given.

Hydration Of Propylene To Isopropanol, Nehemiah Diala

Retrospective Theses and Dissertations

The hydration of propylene to isopropanol was investigated. The first part of this study concerned the direct hydration reaction in various liquid phase systems in the presence of sulfuric acid or p-toluenesulfonic acid. The second part in a two-stage process in which propylene was contacted with excess acetic acid to form isopropyl acetate; the ester was then hydrolyzed to isopropyl alcohol and acetic acid.

The Structure Of O-Antigen From Lipopolysaccharide Of Rhizobium Leguminosarum 128c53 And Its Nod-Fix-Mutant, Tong-Bin Chen

Masters Theses

The LPS of R. leguminosarum 128C53 sm^r rif^r (a streptomycin and rifampicin resistant strain of wild type 128C53) and its mutant ANU54 (nod^-, fix^-) were isolated from the bacterial pellet by hot phenol/water extraction followed by gel filtration chromatography. The O-antigen was isolated by mild-acid hydrolysis of the LPS and purified by gel filtration chromatography using a Sephadex G-50 or G-25. The following results were the same for both the parent and mutant. The composition and linkage of the O-antigen were determined by gas chromatography (GC), GC-mass spectrometry, ¹H and ¹³C nuclear …

Microemulsions, Lyotropic Liquid Crystals, And Other Association Structures, Jiafu Fang

Doctoral Dissertations

"Phase diagrams have been determined showing the extent of the inverse micellar or microemulsion region for several ionic surfactants and some cosurfactants. Hexylamine has been found to be a very effective cosurfactant giving rise to very good water solubilizing capacity at extremely low surfactant concentrations and very low cosurfactant levels at rather high initial hydrocarbon levels.

A fairly extensive study of phase equilibria of the system composed of sodium dodecyl sulfate, hexylamine, heptane, and water has been carried out. The conductivity behavior of the inverse micellar or microemulsion phase of the system shows the percolation phenomenon. Low angle X-ray diffraction …