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- Discontinuous Thermal Expansions and Phase Transformations in Crystals at Higher Temperatures
- The purpose of this investigation is to make more detailed studies of transformations. Fourteen compounds have been examined by high temperature X-ray diffraction for this purpose. The investigations have been carried out in such a way as to reveal: 1. the existence of transformations, 2. the influence of polarizability on thermal expansion, 3. the anisotropy of expansion, and 4. the discontinuity of thermal expansion.
- Magnetic Exchange in Oxovanadium(IV) Complexes with N-Salicylideneamino Acids
- Copper(II) and oxovanadium(IV) ions resemble one another magnetically in having one unpaired electron in their complexes irrespective of their geometrical structures and bond types involved. Copper(II) complexes with antiferromagnetic exchange are well known. On the contrary, antiferromagnetic exchange in oxovanadium(IV) complexes is rather new and not well established. Very few oxovanadium(IV) complexes have been reported to have this anomalous magnetic property. In the investigation of the magnetic properties of oxovanadium(IV) complexes, we have successfully prepared two series of new oxovanadium(IV) complexes with N-salicylideneamino acids.
- Bonding Studies on Organolithium Compounds
- This study is concerned with the nature of the relatively unusual bonding which occurs in organolithium compounds as a direct result of the oligomerization and possible explanations for that bonding.
- Synthesis of Ether-free Organomagnesium Compounds
- At the time this work was begun, there was some confusion about the technique necessary for the successful synthesis of organomagnesium compounds in hydrocarbon solvents and without solvents. It was decided to repeat the work of Bryce-Smith and Zakharkin. Thus began the study of the synthesis of organomagnesium compounds without solvents; the study of the reaction products of these organomagnesium compounds in hydrocarbons plus 2-butanone compared to the reaction products of the corresponding etheral Grignard reagent plus 2-butanone; and a preliminary study of the nature of these organomagnesium compounds in hydrocarbon solvents.
- Some Studies Involving Pyridine N-oxide Reductase
- The study herein described involved the detection of pyridine N-oxide reductase activity in cell-free extracts of E. coli 9723, the determination of co-factors necessary for the enzymatic process, a study of the optimum conditions for enzyme catalysis, and a general characterization of the enzyme.
- Synthesis and Study of Certain Amino Acids Containing the Pyridine Ring
- This study reported herein involves the synthesis and determination of certain biological activities of 4,5-dihydroxy-2-pyridinealanine and the synthesis of 3-pyridine-N-methylalanine.
- Some Studies of Tryosinase Activity in Streptomyces Antibioticus
- The study reported herein concerns itself with the isolation of melaninless mutants of S. antibioticus, ATCC, 3723, and with the demonstration that at least one of the sites of mutation involves that of the enzyme, tyrosinase.
- Preparation of N-Substituted Hydroxylamines from Oxaziridines
- In many series of compounds, intensity of biological activity and chemical reactivity are proportional. Generally whenever a alkyl group replaces a reactive hydrogen atom, as would be the case for an N-substituted hydroxylamine as compared to hydroxylamine, the over-all biological activity of the resulting compound is lower than that of its nonalkylated analogue. Since toxicity and physiological activity are not proportional, this comparison can only suggest possible types of derivatives to prepare and test.
- Corrosion Inhibition with Quaternary Amines
- This thesis describes experiments made to test the corrosion inhibition of quaternary amines on steel.
- Amino Acid Complexes of Rhodium(III)
- This thesis will explore and study rhodium, a group VIII element that has rarely been studied.
- Preparation of 4-Amino-3-Hydrazino-5-Methyl-s-Triazole Dihydrochloride and Condensation Products
- The procedure of Takimoto, Denault, and Hotta was followed in order to prepare 4-amino-3-hydrazino-5-methyl-s-triazole hydrochloride (II) and its precursor, triamino-guanidine hydrochloride (I).
- Synthesis, Stability, and Reactions of Dichloroketene
- The primary objective of this work was to prepare dichloroketene.
- Synthesis of Selected 2-imidazolines
- Since Djerassi and Scholz found that 2-(aryloxy-methyl)imidazolines and their hydrochloride salts exhibit vasoconstrictive properties, the 1,2-(I) 1,3-(II) and 1,4-bis-(2-imidazolinylmethoxy) benzene (III) analogs (Fig. 1, p.2) were chosen for synthesis in order to test them for their effective vasoconstrictive characteristics and for whatever other physiological properties they might exhibit.
- The Coupling Mechanism in the Organolithium-Organic Monofluoride Reaction
- In this work, the principal concern will be with the coupling reaction and it is anticipated that the other reactions referred to above will be considered further when products of the RX-R'Li reactions are discussed.
- Self-Diffusion of Na-²² in Molten PbCl₂-NaCl Mixtures
- This thesis contains the exploration and investigation of self-diffusion of Na-22 in Molten PbCl2-NaCl mixtures.
- Thermal Decomposition of Alkyllithium Compounds in the Pure State
- This thesis is concerned with the thermal decomposition of a series of alkyllithium compounds in the pure state in an attempt to determine the relative stability of alkyllithium compounds and to examine the mechanism of the elimination reaction.
- Self-diffusion of Pb210 and Cl36 in Molten PbCl2-KCl Mixtures in the Region of the Compound 2PbCl2-KCl
- The specific goal of the investigation was the measurement, as a function of temperature, of the self-diffusion coefficients of Pb210 and Cl36 in PbCl2-KCl compositions in the region of the first compound, and to calculate from these data the activation energy necessary for the diffusion of these ions.
- Synthesis, Characterization, and Optical Isomerism of Some Cobalt (III) Complex Compounds
- This thesis investigates the synthesis, characterization, and optical isomerism of some cobalt (III) complex compounds.
- Base Effects on the Thermal Decomposition of Sec-butyllithium Solutions
- The pyrolysis of sec-butyllithium in solution was studied in an attempt to understand the loss of stereo-specificity and the atypical kinetics that have been reported. Additionally, the effect of added lithium alkoxides was studied to determine their effects on the highly reactive sec-butyllithium substrate.
- Electronic Effects in Dihaloketenes
- The objective of this investigation was to determine the electronic effects of the halogen atoms in dihaloketenes such as dichloroketene and dibromoketene.
- Cycloadditions of Dichloroketene
- An investigation of the cycloaddition behavior of dichloroketene with various types of olefins seemed in order to determine if dichloroketene behaved similarly to dialkylketenes. It was anticipated that a study of this type would indicate the reactivity of dichloroketene to various types of olefinic compounds and thus establish if the ease of cycloaddition with dichloroketene parallels the nucleophilicity of the olefin as it does in dialkylketenes.
- Sodium Ion Self-Diffusion in Molten Mixtures
- This work is an extension of Yin's work studying the diffusion of Na ion in the PbCl2-NaCl system, but at more dilute compositions of NaCl.
- A Study of Asymmetric Syntheses in Coordination Chemistry
- Since only one example of an asymmetric synthesis which involved an intermediate containing an optically active ligand has been reported, two questions immediately arise: "Is this type of asymmetric synthesis an isolated example, or is it a stepping stone toward a generalized trend for Co (III) which may be extended to include levo rotatory, as well as dextro rotatory molecules?" In addition, asymmetric synthesis affords a new avenue for synthesizing resolved neutral complexes.
- Diffusion of Na²² in the Molten PbCl₂-NaCl System
- The object of this thesis is to establish the diffusion coefficient of Na ion in PbCl2-NaCl mixtures and to compare its relationship to the other species.
- Reductions of 3,6-diphenyl-s-tetrazines
- In the course of attempting to prepare 3,6-bis(hydroxy-methyl)-s-tetrazine via the reduction of 3,6-bis(carboxy)-s-tetrazine with lithium aluminum hydride, it became apparent that the tetrazine ring was cleaved.
- Preparation of Styrl Derivatives of 2,3-dimethyl-4,9-dioxo-1(2-propyl)-naphth[2,3-d]
- A series of compounds were prepared by condensing 2,3-dimethyl-4,9-dioxo-1-(2-propyl)-naphth[2,3-d] imidazolium iodide with various aromatic aldehydes.
- An Infrared Study of some Ω-Phenyl and Ω-Benzoyl Alkanoic Acids
- There is no available information in the literature on interaction between carboxyl hydrogen and ω-phenyl groups. Consequently, it was of interest to seek such interactions. Some form of interaction is evident from the study of the spectra of some phenylalkanoic acids and benzoyalkanoic acids.
- Synthesis and Infrared Spectra of Substituted Phthalimidines
- A number of N-substituted-3-hydroxy-3-phenylphthal-imidines and some of the isomeric amides have been prepared in order to study changes in the infrared spectra of these compounds due to structural changes in the molecule, particularly with reference to a hydroxyl band at 3.0µ and a carbonyl band at 5.75µ.
- Infrared Studies of Anions of Organic Acids
- The present work is a part of a systematic investigation of the frequency shifts in infrared absorption produced by changing to the anions carbonyl containing acidic compounds.
- Intermediates for Paracyclophane Synthesis
- It is proposed in this thesis that the imperfect systems of Cram and of Schubert be combined with some modifications.
- Diffusion of Pb210 and Cl36 in the Molten PbCl2-NaCl System
- Since 1955 research has been conducted at North Texas State College on diffusion in molten salts. The object of this work was a continuation of the diffusion studies, specifically the diffusion of Pb210 and Cl36 in molten PbCl2-NaCl mixtures.
- The Turbidimetric Determination of Lead
- The turbidimetric method for the determination of lead ion developed in this work is not intended as a replacement for standard analytical procedures, but is presented solely as a laboratory exercise for courses in elementary instructional analysis.
- Infrared Studies of Anions of Barbituric Acids
- As long ago as 1881, it was realized that a functional group of atoms in a molecule would cause an absorption band to appear at a particular frequency in the infrared spectrum of the molecule. In more recent years, the concept of characteristic group frequencies has become firmly established and has resulted in the present widespread use of infrared spectroscopy. There appear to have been relatively few studies of infrared absorption of organic acids as compared with their salts.
- A Study of Some 1-alkyl-1,2-dihydro-3-hydroxybenzo[g]quinoxaline-5,10-diones
- The experiment in this thesis involves a study of some 1-alkyl-1,2-dihydro-3-hydroxybenzo[g]quinoxaline-5,10-diones.
- Optical Properties of Christiansen Filter Systems
- This thesis examines the optical properties of Christiansen filter systems.
- Selective Lipid Absorption
- An experiment was designed to study in the same animal any preferential absorption of a free fatty acid in the presence of a triglyceride of the same fatty acid. Rats were administered a mixture of free fatty acid and its triglyceride labeled with carbon-13 and carbon-14 respectively. Each isotope in the fed lipid and in the lipid recovered from the gastrointestinal tract was measured. The isotope effect, if any, was studied by administering a mixture of palmitic acid-1-C13 and palmitic acid-1-C14.
- Synthesis of Some Amine Steroid Derivatives
- The preparation of 3B-(2-mercaptoethylamino)-cholestane was set as the goal of this thesis project.
- Preparation of Alkoxy Derivatives of 2-Chloro-1,4-Naphthoquinone and 2-Chloro-5(8?)- Nitro-1,4-Naphthoquinone
- This paper studies the the synthesis of certain alkoxy compounds of 2,3-dichloro-1,4-naphthoquinone that can be considered chemotherapeutic agents.
- Synthesis of Polyaldehydes
- Part one of this thesis concerns the polymerizability of some α,β-unsaturated monaldehydes and also relates the synthesis of some new polyaldehydes which have not been reported in the literature. Part two concerns the polymerization of glyoxal, the simplest dialdehyde, and the structure elucidation of this new polymer.
- A Study of Synthesis and Stereoisomerism of some Complex Cobalt Compounds
- The purpose of this investigation is two-fold. Some new complex compounds, where one of the bidentate molecules is an optically active amino acid, were prepared, and attempts to separate those complex isomers by different methods were made. The replacement of the amino acids by optically inactive ligands was studied.
- The Dropping Gallium Electrode in Fused Salts
- This paper is an attempt to appraise the usefulness of the dropping gallium electrode (DGE) in fused LiNO3-KNO3, to compare it with the dropping mercury electrode (DME), and to study the DGE in fused LiCl-KCl.
- Naphth [2,3-d] Imidazoline-2,4,9-Triones
- The study of some acylurea derivatives of 2-amino-3-alkylamino- and -3-arylamino-1,4-naphthoquinones was undertaken to determine the course of reaction under conditions similar to those used by J. R. Hoover and A. R. Day to prepare 2-alkyl-1H-naphth[2,3-d] imidazole-4.9-diones from 2-acylamino-3-amino-1,4-naphthoquinones.
- The Electrochemical Properties of the Mercury/lithium Nitrate-potassium Nitrate Eutectic Interface
- The original purpose of this investigation was to attempt to apply the coulostatic method directly to a molten salt system. The inability to duplicate the reported capacity data for this system resulted in an investigation of the probable cause of this discrepancy between the data obtained by these different methods (14, 15).
- Metal (II) Complexes with N-Salicylideneamino Acids
- Transition metal complexes derived from Schiff bases have rendered an important contribution to the development of modern coordination chemistry. Various stable compounds have been prepared having synthetic, biological, and physicochemical interest. In particular, complexes of salicylaldimines, B-ketoamines, and closely related ligand systems have been investigated.
- Some Studies Pertaining to the Biosynthesis and Metabolism of Asparagine and Lysine in Lactobacillus Arabinosus: I. B-Aspartylhydroxamic Acid: Its Action as a Feedback Inhibitor and a Repressor of Asparagine Synthetase in Lactobacillus Arabinosus II. Purification and Properties of Diaminopimelate Decarboxylase from Lactobacillus Arabinosus
- That Lactobacillus arabinosus 17-5, ATCC 8014, can supply its own requirement for the amino acid, lysine, is demonstrated by the fact that the organism is capable of growth in media devoid of lysine. Since the final biosynthetic step in lysine formation in all bacteria studied to date involves the decarboxylation of meso-dlaminopimelic acid (DAP) to produce lysine, it was of interest to determine whether an enzyme catalyzing such a reaction (DAP decarboxylase) is present in L. arabinosus.
- Nuclear Magnetic Resonance Spectra of Some 1,2,4-triazoles
- In the work undertaken here, NMR has been used to ascertain the structure of some 1,2,4-triazoles. The investigation provides information concerning the structure of potentially tautomeric triazoles such as hydroxy- and aminotriazole. Connected with this aspect of triazole chemistry is the larger problem of mesohydric tautomerism. The present study also yields information for a comparison of substituent effects in triazoles, N-heteroaromatic substances and benzene.
- Kinetics and Mechanism Study of Diphenylketene Cycloadditions
- From a review of the published work in the field of cycloadditions, it is evident that further research is needed to establish the mechanism of ketene cycloadditions. This work was initiated with the intent of obtaining kinetic data which will contribute to the elucidation of the mechanism of ketene cycloadditions.
- Conformationally Stable Cyclohexyllithium Compounds
- Organolitnium compounds have been employed in synthetic worK for many years. However only during the last decade has much progress been made in establishing the mechanistic pathways for the reactions of these compounds.
- Metal Complexes of 2,3-Quinoxalinedithiol
- A series of new planar complexes with the dianion of 2,3-quinoxalinedithiol ligand has been prepared. The complexes have been characterized from the study of their analyses, magnetic moment, conductance, polarograms, electron spin resonance spectra, and electronic spectra, and compared with the available data on the corresponding maleonitriledithiolene and toluene-3,4-dithiolene complexes.
- Organomagnesium Compounds in Benzene Solvent and Their Application in Synthesis of Organoberyllium Compounds
- The work reported by D. Bryce-Smith and G. F. Cox, along with several recent publications describing experimental results designed to elucidate the long disputed question of the structure of the Grignard reagent in ether stimulated the work reported here, in an effort to obtain additional evidence of the structure of the organomagnesium complex in benzene solvent. Since the primary objective of this work was to prepare organoberyllium compounds using the organomagnesium complexes in hydrocarbon solvents, it seemed an insight into the structure of these complexes would be beneficial in this work. The techniques used and experimental evidence obtained from the structure elucidation of the ethereal Grignard reagent have been most helpful in organization of the methods used to study the structure of organomagnesium halide complexes in benzene solvent. It seemed that an insight into the structure of these organomagnesium halide complexes in hydrocarbon solvents would be beneficial in accomplishing the second objective of this work. This objective was to prepare organoberyllium compounds using the organomagnesium halide complexes prepared in hydrocarbon solvents.