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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.
91

The mechanism of acid catalysis of ester hydrolysis ...

King, Cecil V. January 1924 (has links)
Thesis (Ph. D.)--Columbia University, 1924. / Vita. Description based on print version record.
92

Solubility and freezing point depression curves of ester-water systems ...

Harrison, Lilian Elsom, January 1926 (has links)
Thesis (Ph. D.)--Columbia University, 1926. / Vita. Description based on print version record.
93

Reactivities of alcohols in the alcoholysis of esters

Hatch, George Bates, January 1937 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1937. / Typescript. Includes abstract and vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
94

The early effects of phorbol esters in the lymphocyte membrane

Kwong, Cheung Hing. January 1982 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1982. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
95

Adsorption of vapors by metallic oxides; its bearing on the catalysis of ester formation,

Alvarado, Alfonso Miguel, January 1900 (has links)
Thesis (Ph. D.)--University of Iowa, 1924. / Biography.
96

Hydrolysis of organophosphorous esters induced by nanostructured titania-based replicas of diatom microshells

Lee, Seungjin. January 2006 (has links)
Thesis (M. S.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2007. / Huang, Ching-Hua, Committee Chair.
97

Degradation of dimethyl phthalate, dimethyl isophthalate and dimethyl terephthalate by bacteria from deep-ocean sediment

Wang, Yuping, January 2005 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
98

A study of time and temperature variables affecting apolipoprotein B-100 on iodipamide ethyl ester particles /

Alberty, Deborah J. January 1993 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 1993. / Typescript. Includes bibliographical references: p. 90-92.
99

The reactivity of some organophosphorus esters

Eastlick, David Thomas January 1969 (has links)
Part 1: The occurrence of bimolecular nucleophilic aromatic substitution has been established in the reaction of o-dinitrobenzene with triethyl phosphite and diethyl methylphosphonite in acetonitrile solution. There is a fine balance between the customary deoxygenation and nucleophilic substitution of aromatic nitrocompounds. The role of the o-nitro group in facilitating the nucleophilic substitution has been discussed in terms of "built-in solvation" of the reaction centres. The exclusive formation of ethyl nitrite in the reactions has been shown to be compatible with the dealkylation of a quasi-phosphonium intermediate by nitrite ions. Part 2: A series of alkyl a-hydroxyimino-p-nitrobenzyl alkylphophyl adducts have been synthesised from phosphorus-containing acids and p-nitrobenzonitrile oxide. Their solvolytic behaviour has been examined. Hydrolysis occurred in acid solution at 25°with anchimeric assistance of about 2x107 by the neighbouring oximino group, to yield the alcohol of the ester moiety. Exclusive phosphorus-oxygen fission occurred. P-Nitroaniline was formed in alkaline solution by intramolecular attack by the oximate anion, followed by a Lossen rearrangement. Evidence is presented for the intermediary of pentacovalent intermediates, and the relative reactivities of the adducts are explained by the constraints necessary for pseudo-rotation to allow further reaction to form the products in alkaline solution. The acid hydrolysis of ethyl pinacolyl methylphosphonate was shown to proceed via a unimolecular mechanism with the formation of a carbonium ion in 50% aqueous dioxin at 100 °.
100

Controlling Selectivity in Cross-Coupling Reactions with Ester Electrophiles

Masson-Makdissi, Jeanne 07 November 2018 (has links)
First popularized in the 1970s, transition metal-catalyzed cross-couplings now constitute staple reactions for the formation of carbon-carbon and carbon-heteroatom bonds. Recent endeavours in the field have been invested towards expanding the range of compatible coupling partners, with the aim of accessing complex molecules from simple, widely available starting materials. Notably, esters represent an attractive class of alternative coupling partners compared to traditional aryl halides, due to their ubiquity and robustness. Moreover, different cleavage modes can be accessed with esters. Which bond cleavage occurs is highly dependent on which catalyst is used, providing an opportunity to quickly access diverse products from a common precursor. Chapter 1 of this thesis provides a literature overview of cross-couplings with carboxylic acid derivatives to contextualize our contributions described in Chapter 2 and 3. Chapter 2 describes the Pd-catalyzed cross-coupling of phenyl esters with alkyl boranes. Two reaction modes are enabled, namely C(acyl)–O bond activation with carbonyl-retention and C(acyl)–O bond activation with decarbonylation. As such, both alkyl ketones and alkylated arenes are accessed selectively by simple changes in the catalytic system. The disclosed reaction is applied to the diversification of bioactive molecules and discussed in light of recent mechanistic studies of related transformations. In Chapter 3, the first additive-free Ni-catalyzed amidation and transesterification of methyl esters are disclosed. In both transformations, a simple Ni catalyst enables widely available methyl or ethyl esters to be converted into value-added products, producing methanol as the only stoichiometric waste by-product. The Ni-catalyzed amidation protocol strongly contrasts wasteful yet common methods used to convert methyl esters into amides, involving wasteful hydrolysis and coupling with stoichiometric activating agents.

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