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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

A Carbon-13 and Lithium-6 NMR Study of Alkyllithium Compounds

Jensen, Randy M. 12 1900 (has links)
A variable temperature 13C and 6Li NMR study has been conducted for 6Li-enriched ethyl-, n-propyl-, isopropyl-, n-butyl-, isobutyl-, t-butyl--, isopentyl-, 2-ethylbutyl-, and n-hexyllithium in cyclopentane. Significant differences in the 13C NMR parameters are observed as a function of the alkyl group and temperature. These changes are compared to the 6Li spectra and explained in terms of the aggregates present. 13C-6Li coupling is readily observed in both the 13 6 C and Li spectra of compounds which contain branching at either the alpha or beta carbons of the alkyl group. This coupling has been used to identify the aggregates present in solution and to identify the fluxional behavior of these aggregates.
2

Liquid-Phase Oxidation of Para-Cymene: Nature of Intermediate Hydroperoxides and Relative Activity of the Alkyl Groups

Serif, George 05 1900 (has links)
Using photochemical and emulsion pro­cedures, a study has been made of the liquid-phase oxida­tion of p-cymene with respect to the nature of the result­ing hydroperoxides and their decomposition products, and the relative extent of oxidative attack at the methyl and iso­propyl groups. Hydroperoxide decomposition was negligible in the photochemical oxidations at 60C, and the product was shown to consist of 20% primary and 80% tertiary hydroper­oxide by reduction of the total product and fractionation of the resulting alcohols. The following compounds were shown to be present in the emulsion oxidation product in addition to the above mentioned hydroperoxides: dimethyl-p-tolylcarbinol, p-methylacetophenone, p-isopropylphenylcarbinol, cumic acid, p-acetobenzoic acid, p-A-hydroperoxyisopropyl, benzoic acid, and p-(I-hydroxyisopropyl) benzoic acid. By chromatographic separation of the acids and reduction of the other products, the relative extent of attack at the two positions was shown to be 1:4, identical with that of the photochemical oxidation. Pure tertiary hydroperoxide has been obtained for the first time. / Thesis / Master of Science (MS)

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