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A Study of Substituted Diphenylacetic Acids
This thesis describes the creation of substituted diphenylacetic acids and their results.
Hydantoins as Anticonvulsants. VI. 5-Substituted-Mercapto Derivatives of 5-Phenylhydantoin
This thesis describes the process of synthesizing 5-substituted-mercapto derivatives of hydantoin in which the sulfur of the side chain is attached directly to the hydantoin nucleus.
The Synthesis of N-(4-Nitrophenacyl)-4-Alkylpyridinium Halides and Reduction Products
The synthesis of several N-(4-nitrophenacyl)-4-alkylpyridinium halides and their reduction products, 1-(4-aminophenyl)-2-[1-(4-alkylpiperidyl)]ethanols, was undertaken because of structural analogies between these and other physiologically active compounds, such as chloroamphenicol (I), 4,4'-diaminodiphenyl sulfone (II), and 2,2-bis(p-aminophenyl)-1,1,1-trichloroethane (III).
The Development of New Methods for the Quantitative Determinations of Bismuth and Amines
This thesis is a study of the development of new methods for the quantitative determinations of bismuth and amines.
A Comparison of the Achievements of Science and Non-Science Majors Enrolled in General Chemistry at North Texas State College
It is the specific purpose of this investigation to determine the difference, if any, in the amount of practical, everyday chemistry learned by the science majors as opposed to the non-science majors enrolled in general chemistry at the North Texas State College during the school year 1950-1951.
A Chemical, Physical, and Biological Investigation of the Total Suspended and Dissolved Substances in Lake Dallas with Emphasis on Sanitation
The purpose of this investigation is to determine the suspended organic matter and the total phosphorus in the waters of Lake Dallas and to evaluate these findings. Since organic matter floating in lakes is largely composed of minute plants, animals, and detritus derived from animals and plants, the fertilizing effect of phosphorus must be considered as an integral part of this problem.
The Mercury-Sensitized Photochemical Reactions of Isopropyl Benzene and Methylcyclohexane
This thesis describes the theoretical results of mercury-sensitized photochemical reactions of isopropyl benzene and methylcyclohexane. The reactions are carried out and the results are analyzed.
Barbituric Acids as Anticonvulsants. IV. 5-Substituted-Mercapto Derivatives of 5-Phenylbarbituric Acids.
This study involves compounds of the barbituric acid series are well known for their use as anesthetics and sedatives.
Derivatives of Sulfonamide
This thesis describes experiments in creating derivatives of sulfonamide. The derivatives were then submitted for testing for anti-tubercular activity.
Acetophenone Derivatives; N-Diphenylmethyl and N-Fluorenyl Piperidines
This thesis is a study of α-(4-aminophenylsulfonyl)-acetophenone derivatives; n-diphenylmethyl and n-fluorenyl piperidines.
The Attempted Synthesis of some Heterocyclic Sulfones
This thesis describes two experiments: one related to antihistamines, and the other related to antitubercular compounds.
Nitrogen Derivatives of I-phenylazimidoquinone
A series of analogous reactions employing as a nucleus I-phenylazimidoquinone has been investigated.
Applications of Single Reference Methods to Multi-Reference Problems
Density functional theory is an efficient and useful method of solving single-reference computational chemistry problems, however it struggles with multi-reference systems. Modifications have been developed in order to improve the capabilities of density functional theory. In this work, density functional theory has been successfully applied to solve multi-reference systems with large amounts of non-dynamical correlation by use of modifications. It has also been successfully applied for geometry optimizations for lanthanide trifluorides.
Computational Studies of C–H/C–C Manipulation Utilizing Transition Metal Complexes
Density Functional Theory (DFT) is an effective tool for studying diverse metal systems. Presented herein are studies of a variety of metal systems, which can be applied to accomplish transformations that are currently difficult/impossible to achieve. The specific topics studied utilizing DFT include: 1) C–H bond activation via an Earth-abundant transition metal complex, 2) C–H bond deprotonation via an alkali metal superbase, 3) and amination/aziridination reactions utilizing a CuI reagent. Using DFT, the transformation to methanol (CH3OH) from methane (CH4) was examined. The transition metal systems studied for this transformation included a model FeII complex. This first-row transition metal is an economical, Earth-abundant metal. The ligand set for this transformation includes a carbonyl ligand in one set of complexes as well as a phosphite ligand in another. The 3d Fe metal shows the ability to convert alkyls/aryls to their oxidized counterpart in an energetically favorable manner. Also, “superbasic” alkali metal amides were investigated to perform C—H bond cleavage. Toluene was the substrate of interest with Cs chosen to be the metal of interest because of the highly electropositive nature of this alkali metal. These highly electrophilic Cs metal systems allow for very favorable C—H bond scission with a toluene substrate. Finally, the amination and aziridination of C–H and C=C bonds, respectively, by a CuI reagent was studied. The mechanism was investigated using DFT calculations. Presently, these mechanisms involving the use of coinage metals are debated. Our DFT simulations shed some insight into how these transformations occur and ultimately how they can be manipulated.
Synthesis of Gold Complexes From Diphosphine Ligands and Screening Reactions of Heterocyclic Acetylacetonato (ACAC) Ligands with Transitional Metal Complexes
Syntheses of diphosphine gold (I) complexes from gold THT and two ligands, 4, 5-bis (diphenylphosphino)-4-cyclopenten-1, 3-dione (BPCD) and 2,3-bis(diphenylphosphino)-N-phenylmaleimide (BPPM), were done separately. The reactions happened under ice conditions followed by room temperature conditions and produced two diphosphine gold (I) complexes in moderated yield. Spectroscopic results including nuclear magnetic resonance (NMR) and X-ray crystallography were used to study and determine the structures of the products formed. Moreover, X-rays of all newly synthesized diphosphine gold (I) complexes were compared with the known X-ray structures of other phosphine and diphosphine gold (I) complexes. There were direct resemblances in terms of bond length and angle between these new diphosphine gold (I) complex structures and those already published. For instance, the bond lengths and angles from the newly prepared diphosphine gold (I) complexes were similar to those already published. Where there were some deviations in bond angles and length between the newly synthesized structures and those already published, appropriate explanation was given to explain the deviation. Heterocyclic ligands bearing acetylacetonate (ACAC) side arm(s) were prepared from ethyl malonyl chloride and the heterocyclic compounds 8-hydroxylquinoline, Syn-2-peridoxyaldoxime, quinoxalinol and 2, 6-dipyridinylmethanol. The products (heterocyclic ACAC ligands) from these reactions were screened with transition metal carbonyl compounds in thermolytic reactions. The complexes formed were studied and investigated using NMR and X-ray crystallography. Furthermore, the X-ray structures of the heterocyclic ACAC ligand or ligand A and that of rhenium complex 1 were compared with similar published X-ray structures. The comparison showed there were some similarities in terms of bond length and bond angles.
Stereoisomerism of Dimethyl Muconate
The acid which is analogous to the next member of the diphenylpolyenes, 1,4-diphenylbutadiene, is muconic acid. This acid has been chosen to be investigated in an effort to isolate all the stereoisomers of a set containing more than two isomers.
Metallization and Modification of Low-k Dielectric Materials
Aluminum was deposited onto both Teflon AF and Parylene AF surfaces by chemical vapor deposition of trimethylaluminum. This work shows that similar thin film (100 Angstroms) aluminum oxide adlayers form on both polymers at the low temperature dosing conditions used in the studies. Upon anneal to room temperature and above, defluorination of the polymer surfaces increased and resulted in fluorinated aluminum oxide adlayers; the adlayers were thermally stable to the highest temperatures tested (600 K). Angle-resolved spectra showed higher levels of fluorination toward the polymer/adlayer interface region. Copper films were also deposited at low temperature onto Teflon AF using a copper hexafluoroacetylacetonate-cyclooctadiene precursor. Annealing up to 600 K resulted in the loss of precursor ligands and a shift to metallic copper. As with aluminum adlayers, some polymer defluorination and resulting metal (copper) fluoride was detected. Parylene AF and polystyrene films surfaces were modified by directly dosing with water vapor passed across a hot tungsten filament. Oxygen incorporation into polystyrene occurred exclusively at aromatic carbon sites, whereas oxygen incorporation into parylene occurred in both aromatic and aliphatic sites. Oxygen x-ray photoelectron spectra of the modified polymers were comparable, indicating that similar reactions occurred. The surface oxygenation of parylene allowed enhanced reactivity toward aluminum chemical vapor deposition. Silicon-carbon (Si-Cx) films were formed by electron beam bombardment of trimethylvinylsilane films which were adsorbed onto metal substrates at low temperatures in ultra-high vacuum. Oxygen was also added to the films by coadsorbing water before electron beam bombardment; the films were stable to more than 700 K, with increasing silicon-oxygen bond formation at elevated temperatures. Copper metal was sputter deposited in small increments onto non-oxygenated films. X-ray photoelectric spectra show three-dimensional copper growth (rather than layer-by-layer growth), indicating only weak interaction between the copper and underlying films. Annealing at elevated temperatures caused coalescence or growth ...
Reducing the Computational Cost of Ab Initio Methods
In recent years, advances in computer technology combined with new ab initio computational methods have allowed for dramatic improvement in the prediction of energetic properties. Unfortunately, even with these advances, the extensive computational cost, in terms of computer time, memory, and disk space of the sophisticated methods required to achieve chemical accuracy - defined as 1 kcal/mol from reliable experimental data effectively - limits the size of molecules [i.e. less than 10-15 non-hydrogen atoms] that can be studied. Several schemes were explored to help reduce the computational cost while still maintaining chemical accuracy. Specifically, a study was performed to assess the accuracy of ccCA to compute atomization energies, ionization potentials, electron affinities, proton affinities, and enthalpies of formation for third-row (Ga-Kr) containing molecules. Next, truncation of the correlation consistent basis sets for the hydrogen atom was examined as a possible means to reduce the computational cost of ab initio methods. It was determined that energetic properties could be extrapolated to the complete basis set (CBS) limit utilizing a series of truncated hydrogen basis sets that was within 1 kcal/mol of the extrapolation of the full correlation consistent basis sets. Basis set truncation for the hydrogen atom was then applied to ccCA in the development of two reduced basis set composite methods, ccCA(aug) and ccCA(TB). The effects that the ccCA(aug) and ccCA(TB) methods had upon enthalpies of formation and the overall percent disk space saved as compared to ccCA was examined for the hydrogen containing molecules of the G2/97 test suite. Additionally, the Weizmann-n (Wn) methods were utilized to compute the several properties for the alkali metal hydroxides as well as the ground and excited states of the alkali monoxides anion and radicals. Finally, a multi-reference variation to the correlation consistent Composite Approach [MR-ccCA] was presented and utilized in the computation ...
The Chemical Analysis of the Tennessee Green Pod Pole Bean
The object of this paper is to compare the Tennessee green pod pole bean with other beans as to chemical composition and food value.
The Ascorbic Acid Metabolism of Fifty College Women in the North Texas State Teachers College
A study of the ascorbic acid metabolism of a group of fifty college women in the North Texas State Teachers College between the months of April and July, 1943.
Thiophene Analogs of DDT; O-Alkylhydorxylamine Hydrochorides; Dialkylaminoalkyl Esters of Phenoxyacetic Acid
This thesis describes three separate and unrelated chemical experiments. The first investigates analogs for the compound DDT. The second investigates the properties of O-substituted hydroxylamines. The third investigates the action of slight changes to the structure of an antihistaminic agent.
The Synthesis of Certain Alkyl Alpha-(2-Dialkylam Inoalkoxy)Phenylacetates
This thesis describes the procedures used in preparation of the derivatives of certain alkyl phenylacetates and the necessary intermediate compounds. Compounds resembling the structure of Benadryl were prepared in this study in the hope that at least one might prove to be of value in the fight against allergy.
a-Amino Alcohol Derivatives of Methyl P-Nitrophenyl Acetate
This thesis describes the synthesis of a series of dialkylaminoalkoxy derivatives of methyl p-nitrophenylacetate for testing as anti-histamine or hay fever drugs.
The Determination of the Constants in the System of Methyl Alcohol, Acetic Acid, and Water
The purpose of this study is to determine the specific reaction or velocity constants and the equilibrium constant in a system of methyl alcohol and acetic acid, a bimolecular reaction of the second order.
The Storage of Organic Matter in Bottom Deposits of Lake Dallas
The purpose of this investigation is to find which season of the year organic matter increases most in the bottom deposits of Lake Dallas, the reason for the increase, and the amount of organic matter increase from year to year. It is hoped that this study will be beneficial in understanding the conditions in artificial reservoirs.
Synthesis of Antispasmodics
This thesis is a study of the synthesis of antispasmodics.
A Determination of the Value of Sulphur Dioxide as a Dehydrating Agent for Sweet Potatoes
The purpose of this experiment was to determine the value of sulphur dioxide as a dehydrating agent for sweet potatoes.
A Mineral Analysis of the Henrietta Water Supply
The water which supplies the city of Henrietta, Clay County, Texas, is obtained from the Little Wichita River. A concrete dam was built across the river at a point about a mile and a half north of town.
Reactions of Thionyl Chloride, Sulfuryl Chloride, and Chlorosulphonic Acid with Various Types of Hydrocarbons
This study was made to compare rates of reactions between thionyl chloride, sulfuryl chloride, and chlorosulphonic acid, separately, with various types of hydrocarbons.
Use of Chlorosulphonic Acid to Differentiate Hydrocarbon Types
This study investigates the rate of reaction of various types of hydrocarbons with chlorosulphonic acid at the temperature 10 degrees Celsius.
The Synthesis of N-Substituted Di(2-thienylmethyl)acetamides
This thesis is a study of the synthesis of N-substituted di(2-thienylmethyl)acetamides.
The Mercury-Sensitized Photo-Reactions of a Mixture of Propane and Isobutane
It was decided to determine whether or not 2,2,3-trimethylbutane could be formed by the photochemical reaction of isobutane and propane in the presence of mercury vapor energized by ultraviolet radiation from a mercury vapor lamp.
A Quantitative Chemical Analysis of Yellow Dwarf Milo Grain
Evidence indicates that the sorghums were grown as cultivated crops in Egypt as early as 2200 B. C. The sorghums are native to Africa, but indications are that they may have evolved independently in India.
A Study of the Thermal Decomposition Products of Lignite
Lignite is a low grade of coal widely distributed throughout the world. A complete analysis of lignite has not been made, due to the difficulty encountered in the separation of the complex organic compounds bonded therein.
A Fractionation Column for the Separation of Products of the Alkylation of Isobutane and Isobutene
This thesis describes a fractionation column method of separating isobutane and isobutene to isolate isooctane.
Synthesis of 5- (2-Thienyl) Barbituric Acid
A study of the synthesis of 5- (2-Thienyl) barbituric acid.
The Mercury-Sensitized Photo-Reactions of Isobutane
A study of the mercury-sensitized photo-reactions of isobutane.
The Effect of Photo-Sensitized Mercury on Mixtures of Isobutane and Isobutene
A study of the effect of photo-sensitized mercury on mixtures of isobutane and isobutene.
This thesis discusses the preparation of a-(o-nitro-p-methylphenylmercapto)-acetophenone by the reaction between acetophenone and o-nitro-p-methylbenzenesulfenyl chloride in boiling chloroform. The use of stannous chloride in glacial acetic acid for the reduction of nitro groups to amino groups was found generally satisfactory in spite of the difficulty often met with in isolating the amino product.
The Mercury-Sensitized Photo-Reactions of 2,3-Dimethyl Butane
The work encompassed by this thesis is partially a reproduction of the results obtained by John A. Marcia in his work on the photo-chemical reactions of branched hydrocarbons. The previous work done on this particular problem was rendered partially valueless because of the loss of the liquid hydrocarbon product when a fractionation column at the Texas Company Laboratory, Beacon, New York, broke during the fractionation run.
Attempted Synthesis of 5-Allyl-5-(2-Thienyl)-Barbituric Acid
This thesis describes attempts to synthesize 5-allyl-5-(2-thienyl)-barbituric acid as an improved anticonvulsant.
A Study of Sympathiomimetic Amines, Synthesis of O-Alkylhydroxylamines
Although many sympathomimetic amines have been prepared, the perfect one has not yet been made. Chemists are still attempting to synthesize a selective drug with more prolonged effects and free from side reactions or compensatory vasodilation. With this idea in mind it seemed feasible to prepare a group of O-substituted hydroxylamines.
Preparation of Various Amino Alcohol Derivatives of p-Chlorophenoxyacetic Acid and Phenylacetic Acid
This thesis deals with the preparation of dialkylaminoalkoxy derivatives of p-chlorophenoxyacetic acid and phenylacetic acid.
The Synthesis of 5-Alkyl-5-(2-Thienylmethyl)-Barbituric Acids
This thesis describes the synthesis of a series of 5-alkyl-5-(2-thienylmethyl)-barbituric acids.
The Synthesis and Testing of Differential Herbicides
This investigation was limited to the preparation of substituted phenoxyacetic acids and related compounds. The types of substances prepared for testing can, in general, be placed in three groups. These are: aryloxyacetic acids, arylmercaptoacetic acids, and those acids containing the thiophene nucleus.
Determination of the Optimum Concentration of Sulfur Dioxide to be Used in Sweet Potato Dehydration
The object of this paper is to determine the optimum concentration of sulfur dioxide to be used in the commercial dehydration of the sweet potato by this process. Attention has been given to two aspects of the problem, (1) the effect of sulfur dioxide upon the extraction of water from the sweet potato by mechanical means, and (2) the effect of sulfur dioxide upon the stability of the carotene in the sweet potato over a period of several months.
A Qualitative Analysis of the Products of the Reaction Between Chlorosulfonic Acid and 2, 2, 4-Trimethylpentane
This study was made in an attempt to analyze qualitatively the reaction products formed when chlorosulfonic acid reacts with 2, 2, 4-trimethylpentane.
Comparison of Homework Systems (Four Web-Based) used in First-Semester General Chemistry
Web-based homework systems are becoming more common in general chemistry as instructors face ever-increasing enrollment. Yet providing meaningful feedback on assignments remains of the utmost importance. Chemistry instructors consider completion of homework integral to students' success in chemistry, yet only a few studies have compared the use of Web-based systems to the traditional paper-and-pencil homework within general chemistry. This study compares the traditional homework system to four different Web-based systems. Data from eight, semester classes consisting of a diagnostic pre-test, final semester grades, and the number of successful and unsuccessful students are analyzed. Statistically significant results suggest a chemistry instructor should carefully consider options when selecting a homework system.
An Application of the Reformatsky Reaction to the Thiophene Series of Compounds
In view of the increasing importance of thiophene derivatives as chemotherapeutic agents, it was considered of interest to apply the Reformatsky reaction to the synthesis of compounds containing the thiophene nucleus with the thought that these might serve as intermediates for further syntheses.
The Syntheses of Amino Substituted Salicylic Acids and Related Compounds
The introduction of the ether linkage into various compounds imparts physiological activity, hence the synthesis of various ether derivatives involving the phenol group seemed to be a possible route to tuberculostatic substances. The compounds reported in this work are to be tested for tuberculostatic properties by Parke, Davis and Company.