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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.

Regiospecific synthesis of 4-pyridyl-ketones, -esters, and -nitriles, via pyridinium cations /

Lee, Cheuk-man. January 1980 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1981.

Iminiopyridinylpyridinium salts and pyridyl aryl amines derived from them /

Ho, King-wah, Stephen. January 1900 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1982.

The synthesis of novel cyclosexipyridines

Masciello, Lucie. January 2001 (has links)
Thesis (M. Sc.)--York University, 2001. Graduate Programme in Chemistry. / Typescript. Includes bibliographical references (leaves 78-82). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ71605.

Regiospecific synthesis of 4-pyridyl-ketones, -esters, and -nitriles, via pyridinium cations

李卓文, Lee, Cheuk-man. January 1980 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy

Iminiopyridinylpyridinium salts and pyridyl aryl amines derived from them

何景華, Ho, King-wah, Stephen. January 1981 (has links)
published_or_final_version / Chemistry / Master / Master of Philosophy

The catalytic hydrogenation of pyridine at high pressures

Gardner, Lloyd Earl 08 1900 (has links)
No description available.

Untersuchungen in der pyridinreihe ...

Weis, August. January 1905 (has links)
Inaug.-diss.--Technische hochschule "Fridericiana" Karlsruhe.

Fluorimetric analysis of pyridine and its derivatives after hydroxylation with the Hamilton hydroxylation system

Wong, Michelle Pik-Han. January 1978 (has links)
Thesis (M.S.)--Wisconsin. / Includes bibliographical references (leaves 81-83).

Synthesis in the pyridine series : Part 1. The synthesis of new 3,4,5-trialkylated pyridines ; part 2. The synthesis of new 3,5 dimethyl-4-substituted pyridines ; steric effects as an aid to synthesis

Tabata, Takao January 1962 (has links)
PART I A synthetic sequence leading to new and inaccessible 3,4-,5-trialkylated pyridines has been developed 3,4-Dimethyl-5-cyanopyridine was converted to 3,4-dimethyl-5-acetylpyridine on treatment with methylmagnesium iodide and the acetylpyridine was subsequently treated with ethylmagnesium iodide to yield 3,4-dimethyl-5(2-hydroxy-2-butyl)pyridine. Removal of the hydroxyl group was accomplished by means of red phosphorus and hydriodic acid and the resulting olefinic compounds were catalytically hydrogenated to 3,4-dimethyl-5-s-butylpyridine. For further studies in this area, 3,4-dimethyl-5-acetylpyridine was reduced to 3,4-dimethyl-5-ethylpyridine by the Wolff-Kishner reaction and the latter was condensed with benzaldehyde to afford 3-methyl-4-styryl-5-ethyl-pyridine. This, on ozonolysis, was converted to 3-methyl-5-ethyl isonicotinic acid which was subsequently methylated with diazomethane to methyl 3-methyl-5-ethyl-4-pyridine-carboxylate. The nature of the synthesis allows the preparation of virtually any type of 3,4-,5-trialkylated pyridine by straightforward variations at the appropriate stage. PART II In relation to Part I, the synthesis of 3,5-dimethyl-4-substituted pyridines was undertaken. 3,5-Lutidine was reacted with acetic anhydride and zinc to afford in good yield the unexpected 3,5-dimethyl-4-acetyl-pyridine. This was then conveniently converted to 3,5-dimethyl-5-ethylpyridine on reduction with acetic acid and zinc thereby confirming the structure of the acetylpyridine. The acetylpyridine was also reduced with lithium aluminum hydride to 3,5-dimethyl-4-(1-hydroxyethyl)pyridine which in turn was readily dehydrated with phosphorus pentoxide to 3,5-dimethyl-4-vinylpyridine. Both the hydroxypyridine and the vinylpyridine on treatment with hydrobromic acid yielded 3,5-dimethyl-4(2-bromoethyl)-pyridine hydrobromide. This was then converted to 3,5-dimethyl-4-(2-cyanoethyl)pyridine. The preparation of these compounds was possible due to the utilization of the steric effects enforced by the two neighbouring methyl groups at the 3 and 5 positions of the pyridine ring. This sequence of reactions provides a valuable method by which 3,5-dimethyl-4-substituted pyridines can be synthesized owing to the availability of the starting material and to the relatively high yielding reactions. / Science, Faculty of / Chemistry, Department of / Graduate

The system pyridine - hydrogen chloride as an acid medium

Mitchner, Hyman January 1953 (has links)
Pyridine salts were investigated as acids in the pyridine system. The mono and the dihydrochloride salts were found to be the best dissolving reagents for the metals and the sulphides used. Pyridine hydrochloride was most effective in the molten state, whereas pyridine dihydrochloride was found to be quite reactive at room temperature when dissolved in a chloroform solution. Side reactions were investigated and were found to occur only with Mg, Al, and Zn with molten pyridinium chloride. The complex salts, (C₅H₅N.H)₂[MnCl₅]C₅H₅N and (C₅H₅N.H)HgCl₄ were isolated and investigated. / Science, Faculty of / Chemistry, Department of / Graduate

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