Thesis (M.S.)--Wisconsin. / Includes bibliographical references (leaves 60-63).

No description available.

In this report, we described a general method which could regioselectively reduce the carbonyl group on 3-sulfonyl glutarimides and lead to the corresponding hydroxy piperidones (hydroxy lactams) and further converted to 3,4-dihydro-5-tosylpyridin-2-ones .

No description available.

Texte remanié de: thèse--Sc. phys.--Montpellier, 1968. / Extrait du "Bulletin de la Société chimique de France" 1968, n° 12, pp. 4842-4850. Conservé sous la cote: [4° V. 25887 (17)].

A kinetic study of the mechanism of oxidative decarboxylation of α-hydroxy acids by bromine water throughout the pH range revealed two distinct reactions paths. At low pH HOBr rather than Br₂ is the oxidant. The reaction kinetics is complex in bromine water but a second order rate law is observed when the formation of bromide is suppressed by the addition of silver ion,, On the basis of the pH - rate profiles, solvent isotope effect and the insensitivity of reaction rate to α-deuteration it is concluded that HOBr attacks the undissociated hydroxy acid but the rate controlling step also involves a base catalyzed proton loss from the hydroxyl group. Calculated pH - rate profiles, based on a steady state treatment, are in agreement with the observed values for all three model compounds studied in detail: benzilic, mandelic and 2-hydroxy-2-methylpropanoic acids. Rate equations are also derived for the complex reactions occurring in the presence of accumulating bromide. The mechanism of α-hydroxy acid oxidation is compared with the oxidation pattern of alcohols and of oxalic acid in the bromine water system. Above pH 6 molecular bromine is found to be the most important oxidant for α-hydroxy acid. Slow oxidation also occurs by HOBr but not by OBr¯. The reaction is general base catalyzed. A rate expression is derived, based on a steady state treatment, assuming carboxylate - Br₂ and carboxylate - HOBr reactions with concurrent base catalyzed loss of the hydroxylic proton. The calculated rate constants are in good agreement with the values observed both in the presence and absence of added bromide. Results are also presented of: 1) A preliminary investigation of oxidative decarboxylation of α-amino acids by bromine water. 2) A study of the oxidation of α-hydroxy and α-amino acids by permanganate throughout the pH range. / Science, Faculty of / Chemistry, Department of / Graduate

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Chapter one reviews the recent progress in the synthesis of phosphonopeptides, pseudopeptides containing a phosphinic, phosphonic or phosphonamide linkage in place of an amide (peptide) linkage. It describes some of the general methods for the synthesis of these pseudopeptides; for example through couplings to the nitrogen of an α-aminophosphonic acid, or Michael addition to acrylates, as well as other methods, the scope for which are not as wide yet. It also provides a summary of the reported biological activities of this class of pseudopeptides. Chapter two contains the results and discussion for a novel method for the synthesis of α-hydroxy phenylphosphinate oligomers as well as hybrid oligomers containing α-hydroxy phenylphosphinic acid and α-amino carboxylic acids. In particular, synthesis of a series of dimeric α-hydroxy phenylphosphinates are reported. The analysis of these dimers by a combination of NMR spectroscopy, X-ray crystallography and computational methods shows intramolecular hydrogen bonding in these molecules depends on the relative configuration of the carbon and phosphorus atoms. However, although the development of the synthetic methods was successful, the separation and isolation of the diastereomers was not always possible, which hindered a more comprehensive analysis of folding patterns in these molecules. Chapter three contains the experimental procedures, preparation and spectroscopic characterisation of all the chemical compounds. Crystal data and details of crystal structures are in the Appendix.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1969. / Typescript. Vita. Includes bibliographical references.

Pour pallier les inconvénients intrinsèques de l’amidon (hydrophilie, faibles propriétés mécaniques), deux voies de modification de ce polysaccharide ont été étudiées: la substitution des fonctions hydroxy par une fonction chimique hydrophobe de longueur variable d’une part, et le greffage par voie radicalaire de (co)polymères d’acrylate et de styrène d’autre part. Par la première voie, des degrés de substitution (DS) proches de 3 ont été visés conduisant à des matériaux hydrophobes dont la stabilité thermique est nettement améliorée par rapport à celle de l’amidon. Ces matériaux s’organisent sous forme de feuillets contenant les chaines amylacées séparés par les chaines alkyles qui peuvent s’interpénétrer et cristalliser si elles sont suffisamment longues. Le suivi de l’évolution structurale induite par déformation a révélé une orientation des chaînes amylacées parallèle à l’axe de sollicitation dans le cas des matériaux contenant les chaines alkyles les plus longues. La voie du greffage menée sur trois substrats amylacés de Mw distinctes a conduit à l’obtention de matériaux amorphes biphasés composés de chaines amylacés sur lesquelles ont été greffées quelques longues chaines de (co)polymères d’acrylate et de styrène. Ces matériaux hydrophiles liés à leur DS extrêmement faible présentent un comportement fragile dès que l’une des deux phases est à l’état vitreux. / In order to overcome the intrinsic disadvantages of starch (hydrophilicity, low mechanical properties), two modification ways of this polysaccharide have been studied: the substitution of the hydroxy groups by a hydrophobic chemical function of variable length on the one hand, and the radical grafting of (co)polymers of acrylate and styrene on the other hand.Using the first route, degrees of substitution (DS) near 3 were targeted leading to hydrophobic materials whose thermal stability is significantly improved over that of starch. These materials are organized into a sheet-like structure in which the starch chains are organized in planes separated by the alkyl chains which can interpenetrate and crystallize if they are long enough. The study of the structural evolution induced by deformation revealed an orientation of the starch chains towards the draw axis in the case of the materials containing the longest alkyl chains. The grafting way carried out on three starch substrates of different Mw led to the production of two-phase amorphous materials composed of starch chains onto which a few long chains of acrylate and styrene (co)polymers have been grafted. These hydrophilic materials linked to their extremely low DS exhibit a brittle behavior as soon as one of the two phases is in a glassy state.