Thesis (Ph. D.)--University of Wisconsin--Madison, 1967. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

The photochemistry of several tribromo-compounds, R−CBr3 (R = CH2OH, CH2OC(O)CF3, COOH) have been studied by utilizing nanosecond transient absorption (ns-TA) and femtosecond transient absorption spectroscopy. Femtosecond transient absorption experiments showed that isomer species R−CBr2−Br were formed after excitation of R−CBr3 within several picoseconds. The absorption band of the isomers R−CBr2−Br showed a strong solvent dependence upon changing the solvent from cyclohexane to acetonitrile. The absorption wavelength of the proposed isomer intermediates and the spectral shift in cyclohexane and acetonitrile were consistent and supported by results from time-dependent density functional theory (TDDFT) calculations. The decay of the isomer intermediates were significantly shortened by the presence of water and alcohols which indicated that R−CBr2−Br intermediates are likely to react with water and alcohols. Second-order Møller-Plesset perturbation theory (MP2) calculations were employed to investigate the structures and energies of the OH-insertion reactions of R−CBr2−Br when water/alcohol molecules (up to three) were explicitly involved in the reaction complex. The reaction mechanisms examined were found to be dramatically catalyzed by the hydrogen bonding of the water molecules causing the molecule to undergo decomposition. The calculations indicate that the isomer species are able to react with water and alcohol via a water catalyzed OH-insertion/HBr elimination reaction to produce a R−CBr2(OH) product. The ab initio calculations suggested that the R−CBr2(OH) product can undergo a similar water catalyzed reaction mechanism to form R−C(O)Br. The acyl bromide type compounds were also studied using ab initio calculations. The dependence on the substituent group R was found to influence the decomposition pathways that form various final products. The results of the experimental and computational results discussed in this thesis were summarized and some issues were detailed that could be prospects for further study in the future. / published_or_final_version / Chemistry / Doctoral / Doctor of Philosophy

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A kinetic investigation into the enolisation mechanism and enol contents of simple carboxylic acids, esters and amides has been undertaken. Measurement of the enolisation rate constants for malonic acid, ethylhydrogenmalonate and 2- carboxyacetamide were obtained. The halogenation reactions were carried out under conditions where the rate determining step was the enolisation and the reactions were zero order in halogen. The measurements were carried out using u.v./visible spectrophotometry. Results obtained for malonic acid and ethylhydrogenmalonate support the idea of an intramolecular acid catalysed mechanism involving a hydrogen bonded six membered transition state. The enolisation mechanisms were investigated in a number of buffer solutions and were found to be catalysed by general bases. Catalytic coefficients for the following bases were calculated, HO(_2)CCH(_2)CO(_2)-, EtO(_2)CCH(_2)CO(_2)-,ClCH(_2)CO(_2)-, and H(_2)O. Deuterium exchange reactions were monitored using (^1)H N.M.R. and enolisation rate constants for cyano-containing esters and amides were calculated. The results show that the enolisation of amides occurs via an acid catalysed process whereas the enolisation of carboxylic acids and esters proceeds by an intramolecular acid catalysed or a general base catalysed mechanism. Enol contents for simple carboxylic acid derivatives were determined from their reactions with halogens under conditions where the reaction of the halogen with the enol is rate limiting and the reaction is found to be first order in the halogen. It was demonstrated that chlorine, bromine and iodine react with carboxylic ester enols at or very close to the diffusion controlled limit (ca 5x10(^9) 1 mol(^-1) sec(^-1)). The enol contents measured were found to be greater than expected, with the enol content of malonic acid very similar to that of acetone. An estimate of the acidity of carboxylic acid enols has shown them to be strong acids with pK(_a) values in the region 2-5.

Thesis (Ph. D.)--University of Washington, 2007. / Vita. Includes bibliographical references (leaves 144-155).

Thesis (M.S.)--Rochester Institute of Technology, 1991. / Typescript. Includes bibliographical references.

Thesis (Ph. D.), Oregon Graduate Institute of Science & Technology, 1994.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1956. / Typescript. Vita. Includes (as an appendix) 2 reprinted articles from Journal of the American Chemical Society: The iodide ion-promoted dehalogenation of cis- and trans-1,2-dihalocyclohexanes / By Harlan L. Goering and Herbert H. Espy. vol. 77 (1955), p. 5023-5026 -- The solvolysis and base-catalyzed dehydrohalogenation of 1,1- and 1,2-dihalocyclohexanes / By Harlan L. Goering and Herbert H. Espy. vol. 78 (1956), p. 1454-1460. Includes bibliographical references (leaves 62-64, 76).

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