Chemistry Commons^™

Block Copolymer Stabilized Self-Assembled Magnetic Nanoparticles, Li Zhang

Electronic Theses and Dissertations

Magnetic materials are currently being developed in the areas of pharmacology and medicinal chemistry for use in applications such as drug delivery and magnetic resonance imaging. Magnetic fluids are being used in audio equipment and hard disk drives. Their suspension in a particular fluid is promoted by the adsorption or reaction of steric or electrostatic stabilizers, which are appropriate for the particular medium. Critical to the success of these magnetic fluids is the development of the steric stabilizers, which must prevent the coagulation of the metal particles. Polymeric materials are one of the most suitable nonmagnetic media to disperse the …

The Design And Development Of A Comprehensive 49 Locus Y-Str Database For Major U.S. Populations, Paulina Niki Berdos

Electronic Theses and Dissertations

The establishment of a U.S. National Y-STR reference database from a variety of geographically and ethically diverse populations is essential to facilitate the generation of reliable estimates of Y-STR haplotype frequencies. Such multi-locus haplotype frequencies are required to provide a statistical estimate of the significance of a match. Y-STR loci, unlike traditional STR markers, are not independent of one another and are co-inherited as extended haplotypes of linked markers. The estimation of the frequency of occurrence of a particular haplotype therefore necessitates the use of a counting method, which means that the significance of many matches is dependent upon the …

Mitochondrial Dna Analysis By Pyrosequencing, Patsy-Ann Susan Hastings

Electronic Theses and Dissertations

Mitochondrial DNA (deoxyribo nucleic acid) is typically used in forensic casework when small quantities of high molecular weight quality DNA is not expected to be present thus negating the chances of obtaining usable nuclear DNA. Typical samples that utilized mitochondrial DNA analysis are: hair, bones, teeth, ancient remains (samples or remains that are at least 100 years old) or very old samples (samples that are less than 100 but greater than 10 years old). The current method used to evaluate mitochondrial DNA is Sanger sequencing. Although robust, it is also time consuming and labor intensive, on the other hand pyrosequencing …

Stability And Recovery Of Rna In Biological Stains, Mindy Eileen Setzer

Electronic Theses and Dissertations

In theory, RNA expression patterns, including the presence and relative abundance of particular RNA species, provide cell and tissue specific information that could be of use to forensic scientists. An mRNA based approach could allow the facile identification of the tissue components present in a body fluid stain and conceivably could supplant the battery of serological and biochemical tests currently employed in the forensic serology laboratory. Some of the potential advantages include greater test specificity, and the ability to perform simultaneous analysis using a common assay format for the presence of all body fluids of forensic interest. In this report, …

Dehydrobromination Of Some 1,3-Dibromo-1,1- Difluoro Compounds Som (4+2) Cycloaddition Reactions Of 1,1-Difluoro-1,3-Dienes, Christopher Foti

Retrospective Theses and Dissertations

The title 1,3-dibromo- l, l-difluoro compounds are dehydrobrominated in the presence of l,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Reaction of simple saturated dibromides with DBU at 25 °C affords moderate yields of monoelimination products in which the reaction is 100% stereoselective and regioselective. Highly conjugated dienes are synthesized at mild reaction conditions in contrast to simple alkyl or pentafluorophenyl dienes which are inaccessible via a double dehydrobromination reaction due to the unexpected formation of trifluoromethyl compounds. Aromatic gem-difluorodienes react with 4-phenyl-1,2,4-triazoline-3,5-dione and a mechanistic experiment demonstrates the relative reactivities of the isomers of 1, l-difluoro-4-phenyl-1,3-butadiene in a Diels-Alder reaction. The unfluorinated analogue of 1, …

Improving The Analytical Recovery Of Radiostrontium From Environmental Samples, Luz Selenia Acosta

Retrospective Theses and Dissertations

No abstract provided.

The Enhancement Of The Incineration Of Model Volatile Organic Solvents By The Use Of Hydrogen Peroxide As A Novel Oxidative Homogeneous Catalyst, Douglas James Tomlin

Retrospective Theses and Dissertations

No abstract provided.

I. Evaluation Of Iron Whiskers And Stainless Steel Microwaves As Catalysts For Ammonia Synthesis Ii. Hydrodechlorination Of Chloralkanes On Iron Whisker Catalysts, Diane Kaefer-Northcott

Retrospective Theses and Dissertations

This report consists of two parts. Part I concerns the evaluation of stainless steel microwires and iron whiskers, as catalysts for ammonia synthesis. Several comparison catalysts were also evaluated for their catalytic ability for ammonia synthesis. The effect of potassium promotion on filament and comparison catalysts was determined.

Part II concerns the evaluation of iron whisker catalysts with regard to their catalytic ability for their hydroechlorination fo chloroalkanes. The chloroalkanes that were used in the hydroechlorination reactions were carbon tetrachlorida, chloroform, methylene chloride, and 1, 1, 1-trichloroethane. The hydroechlorination reactions were conducted in the gas phase, either in the prsence …

New Synthetic Transformations Of 1-Benzyl, 3,5-Dibromo, 1h-1,2,4-Triazole /C, Adam Michael Fivush

Retrospective Theses and Dissertations

This report details the study of the nucleophilic substitution of 1-benzyl-3,5-dibromo-lH-1,2,4-triazole. A variety of nucleophiles have been studied to date. The nucleophiles studied primarily fall into the categories of Phosphorous, Oxygen and Sul fur species. Some of the initially formed substitution products are thermally unstable and undergo unique rearrangements. The report describes the physical properties, 1H NMR, 13c NMR, IR and Mass spectra for all of the synthesized compounds. Possible mechanistic pathways are presented for the formation of the prepared compounds. Recommendations are made in order to suggest future research opportunities in this area.

Unexpected Products From The Reactions Of 1-(Bromodifluoromethyl)-2-(Bromoalkanes With Potassium Hydroxide,Characterization Of Some Gen-Difluorodienes And Attempted Syntheses Of Gem-Difluorocyclopropanes, Mariana Michael

Retrospective Theses and Dissertations

This research report discusses the reactions of CF2Br2 with various alkenes. Attempts to synthesize some gemdifluorocyclopropanes from alkenes and CF2x2 (X=Br, I) by modified Simmons-Smith procedures were Dehydrohalogenation reactions of some not successful. 1,3-dibromo-1,1- difluoroalkanes were conducted with potassium hydroxide or tributylamine. Heating cis or trans 1-(bromodifluoromethyl)- 2-bromocyclohexane with potassium hydroxide does not produce the expected gem-difluorodienes but instead gives the corresponding a,$ -unsaturated carboxylic acid. The mechanism for the productions of the various reaction intermediates from the reaction of the cyclic dibromide with potassium hydoxide is proposed. Experimental evidence supporting the proposed mechanism is presented. Gemdifluorodienes are isolated when …

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.

Preparation Of Geminal Diflourodienes, Antonio Landavazo

Retrospective Theses and Dissertations

This report discusses research involving the preparation of germinal difluorodienes. Free radical addition of dibromodifluoromethane to 1-hexene and cyclohexene was performed, followed by a double dehydrohalogenation to yield 1,1-difluoro-1,3-heptadiene and 3-(difluoromethylene)cyclohexene, respectively. NMR, IR, and mass spectral data were obtained and presented as groundwork for further research. A study comparing the free radical initiators, benzoyl peroxide and 2,2’-azobis-(2-methyl)proprionitrile (AIBN) was included, showing neither as ideal initiators for the free radical additions performed. The relative stabilities of the bromodifluoromethyl and the difluoroiodomethyl radicals were approximated. A Diels-Alder reaction of 1,1-difluoro-1,3-heptadiene with 4-phenyl-1,2,4-triazoline-3,5-dione produced the expected [4 + 2] cycloadduct in good …

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 Reaction Of 2-Arylprop-1-En-3-Yltrimethylammonium Iodides With Sulfur Nucleophiles And Useful Synthetic Applications Of These Adducts, Steven J. Duranceau

Retrospective Theses and Dissertations

This report discusses research involving the reactions of 2-arylprop-1-en-3-yltrimethyl ammonium iodides with sulfur nucleophiles and the useful synthetic applications of the adducts formed. The present work may be subdivided into four sections: 1) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with benzenethiol; 2) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with the sodium salt of benzenesulfinic acid; 3) reactions of several 2-arylprop-1-en-3-yltrimethylammonium iodides with 2-mercapto-1-methyl imidazole; and 4) oxidation of 2-aryl-3-phenylthio-1-propenes and 2-aryl-3-phenylsulfonyl-1-propenes using sodium perborate. This report outlines the experimental conditions and procedures responsible for the synthesis of these products; in addition, this report describes the physical properties, NMR and IR spectra of …

Flow Injection And Photometric Determination Of S(Iv) In Rainwater With Pararosaniline, Frank A. Hedgecock

Retrospective Theses and Dissertations

The photometric pararosaniline (pRA) method for determination of S(IV) has been adapted to flow injection sample processing (FIA). Prominent features of the method include a limit of detection of 0.010 ppm of dissolved sulfur dioxide and a sampling rate of 20 per hour. The concentration range investigated was 0.010 to 0.200 ppm S0₂. Sequential samples were collected from two rainstorms and SO₂ concentrations were measured for 19 samples. The suppression of interference by Cr(III), Mn(II), and Fe(III) using 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA) and ethylenediaminetetraacetic acid (EDTA) was investigated. A comparison of the adapted FIA method and its parent …

The Use Of Scheffe-Equivalent Equations To Predict Physical Properties Of Neoprene, Cheng Y. Loh

Retrospective Theses and Dissertations

The goal of this study is to find a more organized and directed approach to build models for mixture systems. An attempt is made to generate and then compare Scheffe (mixture) models with those generated by McGee using the ‘conventional’ method for neoprene data. The models are judged on their ability to predict physical properties of neoprene by comparing the following: predicted and actual values by inspection; the calculated % error of prediction; the squared multiple correlation coefficients; adjusted squared multiple correlation coefficients; the Fisher statistic and significance probability. Scheffe models do not have an intercept term and test statistics …

Ion Selective Electrodes Based On Aza- Substituted Crown Ethers, Lisa Ann Wellington

Retrospective Theses and Dissertations

A cation-responsive electrode system has been developed which incorporates aza-substituted crown ethers as ligands. In a novel application, uncomplexed crown ethers were used in the pelletized form for ionic transport. Electrodes have been produced which can be conditioned for a particular ion and following their use, be reconditioned and reused for other ions. Preparation method and lifetime studies are included.

The responses of two crown ethers with plasticizers were evaluated for thirteen representative cations. The concentration range covered in each evaluation was 1 x 10^-1 to 1 x 10^-7 M. For those ions exhibiting Nernstian or near-Nernstian response, …

New Synthetic Applications Of Enaminoketones, Timothy J. Buck

Retrospective Theses and Dissertations

This report discusses research concerning synthetic applications of enaminoketones. The work may be divided into four parts as follows: a) replacement of the dimethylamino group of certain enaminones by other amine groups through a simple procedure; b) formation of 3-alkyl-pyrazoles; c) formation of 2-amino-4-alkyl-pyrimidines; d) synthesis and subsequent reduction of iminium salts. The starting materials (E-1-(N,N-dimethylamino)-1-alkene-3-ones) have been condensed with hydrazine and guanidine to form pyrazoles and pyrimidines, respectively. The same starting materials have been reacted with POCl₃ in CH₂Cl₂ to produce chlorovinyliminium salts. These have then been reacted in situ with reducing agents to produce …

Attenuation Of Infrared Radiation By Diesel Fuel Generated Particle And Droplet Aerosols, Soodabeh Karimi

Retrospective Theses and Dissertations

The object of this project was to explore the absorbance and scattering properties of carbon particle smoke in the infrared and visible regions of the spectrum. Laboratory scale apparatus were developed to produce smoke in the form of carbon particles, droplet aerosols and combinations of the two. These smokes were made from diesel fuel and fog oil.

I. The Use Of Polyethers As Phase Transfer Catalysts For The Fluoroalkoxylation Of Halogenated Aromatic And Heteroaromatic Systems Ii. The Grignard Addition And Sodium Cyanoborohydride Reduction Of Arylchloropropeniminium Salts, Martin A.M. Moebus

Retrospective Theses and Dissertations

This research addresses two distinct areas of synthetic organic chemistry: the use of phase transfer catalysts for the fluoroalkoxylation of activated haloaromatic and haloheteroaromatic systems, as well as the Grignard addition and sodium cyanoborohydride reduction of aryl chloropropeniminium salts. In Part I of this research, a number of macrocyclic- and linear polytethers were studied as phase transfer catalysts in the nucleophilic aromatic substitution of haloaromitc systems. The most effective catalyst was determined to be poly(ethylene glycol)-8000 and the reaction conditions were optimized for this catalyst. Subsequently isomer reactivity, effects of activating groups, effects of leaving groups, and nucleophiles were studied …

Synergistic Effects In Bimetallic Hydrogenation Catalysts, Kathleen L. Mcintyre

Retrospective Theses and Dissertations

Mono and bimetallic catalysts of varying composition were prepared in order to examine any synergistic effect that may occur by mixing metals on a support. The test reactions were hydrogenation of 1, 3-butadiene and piperylene, a mixture of similar boiling 5-carbon olefins. Catalysts containing ruthenium and rhodium displayed some synergistic effects when supported on silica gel and 13X molecular sieves. The use of 5A molecular sieves as a support was used to examine the feasibility of selective hydrogenation as a separation tool for the piperylene mixture.

The Determination Of Biological Activity And Biochemical Mode Of Action For The Oxadiazole And Diacylhdrazine Insecticides, Bonnie M. Gunn

Retrospective Theses and Dissertations

This report includes the determination of activity and possible mode of action for a group of potential new insecticides. The biological screening procedure was developed using Drosophila melanogaster as the test organism while Musca domestica was used for mode of action assays. The percent kill for each compound is based on the number of eggs placed on media containing the insecticide minus the number of adults enclosed as compared to the control media reared flies. Observations were made on all stages from eggs through adults to determine time of death and if any malformations were present. These observations aided in …

A Two Part Research Report: Aromatic Nucelophilic Fluoroal Koxylation Via Cationic Phase Transfer Catalysis And Reactions Of Unsymmetrical Vinamidinium Salts With Organometallic Reagents, Joseph E. Coury

Retrospective Theses and Dissertations

This report discusses research which was conducted in two areas: the study of aromatic nucleophilic fluoroalkoxylation assisted via cationic phase transfer catalysis and the study of unsymmetrical vinamidinium salts and their reactions with organometallic reagents.

Sodium alkoxides have been successfully used to fluoroalkoxylate activated halo- aryl and heteroaryl substrates under phase transfer catalysis conditions. Optimum reaction conditions incorporated tetra-n-butyl-phosphonium bromide as the catalyst and refluxing toluene as the solvent medium. Different quarternary phosphonium and arrmonium salts have been evaluated as catalysts: also, the effects of activating groups, leaving groups, and nucleophiles have been reported.

The reaction of 3-dimethylamino-3-phenyl-prop-2-en-l-ylidendimethyliminium perchlorate with …

A Three Part Research Report: The Synthesis Of Potential Insecticides, N-(4-Heteroaryloxybenzoyl)-N'-(2,4-Dichlorobenzoyl) Hydrazines: A Reinvestigation Of Hexamethylphosphoramide With Ketoximes; Regioselective Fluoralkoxylation And Polyfluoroalkoxylation Of Activated Dihalobenzenes And Dihaloheterocycles, Gary A. Decrescenzo

Retrospective Theses and Dissertations

This report discusses research in three areas of organic synthesis: The synthesis of potential insecticides; the reinvestigation of the reaction of hexamethylphosphoramide with ketoximes; and the regioselective fluoroalkoxylation and polyfluoroalkoxylation of activated dihalobenzenes and dihaloheterocycles. In Part I, a series of N-(4-heteroaryloxybenzoyl)-N'-(2, 3-dichlorobenzoyl) hydrazines are synthesized, and attempts at cyclic dehydration to the corresponding 2, 5-disubstituted-1, 3, 4-oxadiazoles are discussed. In Part II, the synthesis of N, N-dimethyl-N'-aryl amidines by the reaction of aryl alkyl and diaryl ketoximes with HMPA is discussed. In Part III, a series of activated dihalobenzenes and dihaloheterocycles are reacted with sodium trifluoroethoxide to study the …

Oxidation Of Valencene To Nootkatone, Tung F. Chen

Retrospective Theses and Dissertations

The liquid phase autoxidation of the readily available sesquiterpene valencene to the commercially important perfuming agent nootkatone utilizing gaseous oxygen at atmospheric pressure has been investigated. Catalyst systems involving transition metal salts and complexes, and phase-transfer catalysts have been evaluated under different conditions of valencene concentration, catalyst concentration, reaction temperature, solvent and oxygen flow rate. Of eighteen candidate catalysts for the oxidation of valencene to nootkatone, chlorocarbonylbis (triphenylphosphine) iridium (Vaska's catalyst) demonstrated good activity and appeared to show the best potential for future work.

Modeling Of Laboratory Scale Batch Distillations With A Desktop Computer, Dale F. Johnson

Retrospective Theses and Dissertations

A program has been written that simulates the operation of a batch distillation process. The program has been implemented on a Hewlett-Packard 9845T minicomputer and will be used as an instructional aid in a graduate level chemistry course. The program is very user interactive and is capable of using the final conditions from one run as the initial values of the next simulation. The batch simulation is achieved by using a tray-by-tray algorithm and is equipped with three integration techniques; the Euler, the Modified Euler and the 4th order Runge-Kutta methods. The program has the capability for studying the effect …

I :Synthesis And Evaluation Of Polymer Supported Homogenous Oxidation Catalysts. Ii: Synthesis And Evaluation Of Polymer Supported Multi Site Phase Transfer Catalysts Iii: Synthesis Of Potential Herbicides, Russell L. Leonard

Retrospective Theses and Dissertations

This report consists of three parts. Part I involved the synthesis and evaluation of some polymer supported homogeneous oxidation catalysts – specifically, the synthesis of polystyrene 2(bis-salicylaldehyde) 2-methyl propylene-1, 3-diiminato cobalt (II) and polystyrene 2(bis-2, 4-pentanedione) 2-methyl propylene-1, 3-diiminato cobalt (II). Part II involved the synthesis of both soluble and insoluble phase transfer catalysts designed to catalyze nucleophilic substitution reactions. Trisite quaternary phosphonium and disite quaternary phosphonium salts were prepared. Part III involved the synthesis of several potential herbicides.

Part I: The Synthesis Of Potential Agrochemicals. Part Ii: The Use Of Gold's Reagent As A Lynch Pin In The Formation Of Five And Six Membered Heterocycles, Keith F. Correia

Retrospective Theses and Dissertations

This research report focuses on two topics: the synthesis of potential agrochemicals and the use of Gold's reagent as a lynch pin to form five- and six-membered heterocycles. A diacyl hydrazide and two oxadiazoles are prepared for use as possible insecticides. Gold's reagent behaves as a one-atom and two-atom lynch pin when reacted with 1, 4- and 1, 5-dinucleophiles, respectively. Reaction conditions, interpretation of spectral data, and recommendations for further research are provided.

Part I: The Synthesis Of New Potential Insecticides. Part Ii: New Aromatic Nucleophililic Subsitution Reactions, Fluoroalkoxylation And N,N-Dimethylamination, Cesar Colon

Retrospective Theses and Dissertations

A series of routes are described for the synthesis of new potential insecticides which are symmetrical or asymmetrical similogs of 2,5-Bis (dichloropheny1)-1,3,4-oxadiazole and its precursor diacyl hydrazine. Also two new aromatic nucleophilic substitution reactions are discussed. Activated aryl halides are reacted with fluorinated alkoxide anions. In all cases, substitution of the halogen by a fluoroalkoxy group was observed, and activated aryl halides are reacted with HMPA as an N, N-dimethyl aminating agent. In all cases, substitution of the halogen by a dimethyl amino group was observed. The effect of the activating group and the leaving group is described and a …

The Synthesis Of Potential Insecticides: Haloalkoxy Phenyl Diacylydrazines And 1,3,4-Oxadiazoles, Kathleen S. Gibbs-Rein

Retrospective Theses and Dissertations

The syntheses of two classes pf compounds, diacylhydrazines and 2,5-disubstituted 1,3,4-oxadiazoles, intended for subsequent investigation of pesticidal activity are discussed. The experimental conditions and procedures necessary for the preparation of these potential insecticides are also revealed. Finally, spectral data are interpreted and explained, and recommendations for further research are given.