Article on electronic and transport properties of artificial gold chains.

Article on band structure and quantum conductance of nanostructures from maximally localized Wannier functions.

Problems presented in this paper concern the chemical equilibrium of methyl alcohol, formic acid, and methyl formate when combined.

This study deals with the (4+2)-cycloaddition reactions of 4-π electron compounds with ketenes. Chloroketenes were generated in situ from the corresponding chlorinated acid chlorides in the presence of the ketenophiles. Chloro-, dichloro- and diphenylketenes reacted with 1-methoxy-3-trimethylsiloxy-l,3-butadiene, and 2,4-bis(trimethylsiloxy)-1,3-pentadiene to yield the corresponding dihydropyrans. The dihydropyrans yielded substituted 4-pyranones on hydrolysis.

The reactions of tert-butyl-, sec-butyl-, and n-butyllithium with dimethylfluorovinylsilane include addition to the double bond to give both silene and silenoid intermediates, fluorine substitution, and a novel vinyl substitution. For the tert-butyllithium reaction, product stereochemistry and trapping experiments using both cyclopentadiene and methoxytrimethylsilane show that silenes are not formed in THF. In hexane about 67% of the 1,3-disilacyclobutanes obtained arise from silene dimerization while 33% are formed by silenoid coupling. In hexane the order of reactivity for addition, t-Bu > sec-Bu > n-Bu, is opposite that for fluorine substitution. The vinyl substitution is most significant with secondary alkyllithium reagents including the tert-butyllithium adduct to dimethylfluorovinylsilane and with sec-butyllithium itself. Evidence for the formation of vinyllithium or ethylene in the process could not be obtained.

A study has been conducted for the qualitative and Quantitative analysis of chlorinated organic compounds in water. The study included the adaptation of Amberlite XAD macroreticular resin techniques for the concentration of municipal wastewater samples, followed by GC/MS analysis. A new analytical method was developed for the determination of volatile halogenated organics using liquid-liquid extraction and electron capture gas chromatography. And, a computer program was written which searches raw GC/MS computer files for halogen-containing organic compounds.

This thesis examines the use of zinc for electroplating and compares its use to other metals. Experiments conducted to gather data indicated circumstances which resulted in optimal results.

This thesis explores the Hicoria genus and focuses on the Stuart variety of pecan tree. Experimentation yielded the ash constituents, fats, fat constants, crude fiber, protein, and sugar in shelled pecan samples.

This thesis explores the seperation of isomeric paraffins in organic chemistry and how the resulting mixture of hydrocarbons might be examined.

Ketene dimethyl thioacetal monosulfoxide was prepared in 68% overall yield in two steps starting from methylmagnesium chloride. The yield of dithioacetic acid was improved significantly by employing tetrahydrofuran as solvent and using elevated temperatures. A one-pot synthesis of ketene thioacetals from alkyl halides was developed and several ketene thioacetals were prepared by this method. Direct oxidation of ketene thioacetals using m-chloroperoxybenzoic acid provided a general route to ketene thioacetal monosulfoxides. In cases where E and Z isomeric ketene thioacetal monosulfoxides were possible, the E/Z isomeric ratio increased as the substituents on the ketene double bond was increased in size.

The reaction of tert-butyllithium with chloromethylphenylvinylsilane at low temperatures in hexane gave a 48% yield of a mixture of the five isomers of 1,3-dimethyl-1,3-diphenyl-2,4-dineopentyl-1,3-disilacyclobutane, formed by the head-to-tail dimerization of both E- and Z-1-methyl-1-phenyl-2-neopentylsilenes, along with an acyclic dimer. These were separated and their stereochemistry was established by ('1)H- and ('13)C-NMR spectroscopy. The E- and Z-silenes were also trapped as their {4 + 2} cycloadducts with cyclopentadiene, 2,3-dimethyl-1,3-butadiene and anthracene, which also were separated and stereochemically characterized. A consistent mole ratio of 70:30 for the E- and Z-silene adducts is interpreted as evidence for stereochemical induction in the silene generation reaction. It is also suggested that the dimerization of the silenes to give the 1,3-disilacyclobutanes occurs by a nonstereospecific stepwise pathway. When E- or Z-1-methyl-1-phenyl-2-neopentylsilene was generated by the retro-Diels-Alder flow vacuum thermolysis of its corresponding cyclopentadiene or anthracene adduct at temperatures between 400 and 600(DEGREES)C and then trapped with 2,3-dimethyl-1,3-butadiene, the stereochemical distribution of the products is independent of the stereochemistry of the silene precursor, indicating that the silene is not configurationally stable towards cis-trans isomerization at these temperatures. Evidence that the intermolecular ene reaction and the {4 + 2} cycloaddition which occur with 2,3-dimethyl-1,3-butadiene are concerted is presented. …

The objective of this study was to develop new synthetical routes to natural and industrial products utilizing ketene cycioaddition reactions. The cycioaddition of diphenylketene with α,β-unsaturated imines yields (2+2) cycioaddition products, g-lactams. However, electron donating groups, such as dimethylamine, in the 4-position of the α,β-unsaturated imines result in (4+2) cycloaddition products, ∂-lactams. Dichloroketene reacted with α,β-unsaturated imines to yield (4+2) cycloaddition products, g-lactams. Large substituents in the 4-position of a, ^-unsaturated imines resulted in a (2+2) cycioaddition product, β-lactam. The ∂-lactams derived from dichloroketene are easily dehydrochlorinated to the corresponding 2-pyridornes.

This thesis presents findings of experiments conducted to determine the most feasible method to electroplate metal.

This study examines history, climate, and distribution in relation to the chemical content of yellow dent corn.

This study is the result of tests conducted to determine the adaptability of the human eye to darkness.

This thesis resulted from analysis of the water in Lake Wichita so that sources of water content could be determined.

A study to determine the organic content of Lake Dallas, and study the influence on plankton growth.

Photocopy of a dissertation discussing natural radioactivities and half life of potassium, Rubidium, Rhenium, and Lutetium.

The reaction of 2-[(diphenylphosphino)methyl]-6-methylpyridine (PN) with Os3(CO)12-n(MeCN)n [where n = 0 (1), 1 (2), 2 (3)] has been investigated. Os3(CO)12 reacts with PN in the presence of Me3NO to afford the clusters Os3(CO)11(1-PN) (4) and 1,2-Os3(CO)10(1-PN)2 (5). X-ray diffraction analyses confirm the equatorial coordination of the phosphine(s) in 4 and 5, with the two phosphines in the latter cluster exhibiting a 1,2-trans orientation about the Os-Os vector that contains the two ligands. Treatment of the MeCN-substituted cluster Os3(CO)11(MeCN) and PN (1:1 ratio) in CH2Cl2 gives clusters 4 and 5, in addition to HOs3(η1-Cl)(CO)10(1-PN) (6) as a result of competitive activation of the reaction solvent. Cluster 6 contains 48e- and the diffraction structure reveals the presence of axial chloride and equatorial phosphine ligands which are located on adjacent osmium atoms. The bridging hydride ligand in 6 spans the Cl,P-substituted Os-Os vector. The reaction of Os3(CO)10(MeCN)2 with PN furnishes 5, 6, and 1,1-Os3(CO)10(2-PN) (7) in yields that are dependent on the reagent stoichiometry and reaction solvent. The solid-state structure of 7 confirms the chelation of the PN ligand to a single osmium atom via the pyridine and phosphine moieties at axial and equatorial sites, respectively. The bonding in 7 relative to other …

The laser Raman spectra of tetrachlorocyclopropene in the liquid and solid phases have been recorded and vibrational assignments are presented. These results along with root mean squared vibrational amplitudes from electron diffraction data have been employed in a normal coordinate analysis in which a 19 parameter potential function is refined. This potential function, originally expressed in terms of compliance constants, is then used to derive the corresponding conventional and relaxed force constants.

Article on rate constant and branching fraction for the NH₂ + NO₂ reaction.

Article on the oxidation of reduced sulfur species and carbon disulfide.

This article uses equations for partition coefficients of compounds from water and the gas phase to various solvents to obtain descriptors for pentane-2,4-dione and 21 of its derivatives.

This article discusses group-transfer reactions of nickel-carbene and -nitrene complexes with organoazides and nitrous oxide that form new C=N, C=O, and N=N bonds.