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61	Application of the Baylis-Hillman methodology in the construction of novel heterocyclic derivatives Nyoni, Dubekile January 2008 (has links) Baylis-Hillman reactions of 2,2’-dithiodibenzaldehyde with the acyclic alkenes, methyl vinyl ketone (MVK) and methyl acrylate have afforded the thiochromene derivatives in moderate yields, and this approach has been extended to the use of the cyclic alkenes, 2-cyclohexenone and 2-cyclopentenone to afford the tricyclic analogues. In all cases, reduction of the disulphide link and intramolecular cyclisation occurred in situ, and a preliminary kinetic study of this reaction using the acyclic substrates MVK and methyl acrylate was undertaken with the aim of elucidating the mechanism involved. The results obtained showed that the consumption of both 2,2’-dithiodibenzaldehyde and MVK and/or methyl acrylate followed 1st-order kinetics during the initial stages of the reaction, but then deviated from 1st-order linearity. The reaction with methyl acrylate was much slower than with MVK, and the kinetic data indicates the mechanism to be more complex than anticipated. Conjugate addition reactions of methyl acrylate-derived 2-nitrobenzaldehyde Baylis-Hillman adducts with the amines, piperidine and benzylamine, afforded a range of conjugate addition products as diastereomeric mixtures in excellent yield (80-100%). Catalytic hydrogenation of the conjugate addition products using a Pd-C catalyst in ethanol, has afforded the corresponding, novel 3-amino-2-quinolone derivatives in lower yield (22-37%).The application of [superscript 13]C NMR prediction programmes to selected compounds synthesized in this study has revealed reasonable correlations between the experimental and predicted values. Heterocyclic compounds -- Derivatives
62	Complex formation between heterocyclic compounds and polynitro benzene derivatives McEwen, Kathleen Lenore January 1953 (has links) Complexes formed between heterocyclic compounds and polynitro benzene derivatives have been examined spectroscopically. It has been found that many complexes, when irradiated in the region of their charge-transfer absorption emit a short-lived radiation in the region of the heterocyclic triplet. There is some evidence for a radiationless transition from an excited, bonding charge-transfer state to the excited triplet level of the heterocyclic component. / Science, Faculty of / Chemistry, Department of / Graduate Heterocyclic compounds Benzene
63	Synthesis of beta-lactams Zamboni, Robert Joseph. January 1978 (has links) Note: Antibiotics. Heterocyclic compounds.
64	A study of some five-membered oxygen heterocycles / Snyder, Carl Henry January 1958 (has links) No description available. Chemistry Heterocyclic compounds
65	Synthesis and characterization of selected boron heterocycles / McAchran, Gerald Eugene January 1964 (has links) No description available. Chemistry Boron Heterocyclic compounds
66	The synthesis and reactions of 4H-thiopyran-4-one 1, 1-dioxide and derived cage molecules / Wise, Lawrence David January 1967 (has links) No description available. Chemistry Heterocyclic compounds
67	The chemistry of cyclooctatetraene dianion / Antkowiak, Thomas Anthony January 1968 (has links) No description available. Chemistry Heterocyclic compounds
68	The effect of ether oxygen in the chemistry of medium-sized rings / Scott, Malcolm Keith January 1972 (has links) No description available. Chemistry Heterocyclic compounds
69	Studies in some novel heterocycles : I. The synthesis and chemistry of pyrrolo- and furo-[2,3-D]pyrimidines. II. The synthesis toward nucleoside Q / Liu, Sai-Ho Paul January 1978 (has links) No description available. Chemistry Heterocyclic compounds
70	Synthesis of sulfur and seleniumn heterocycles, including derivatives of imidazopyridine and benzimidazole / Björk, Malin, January 2005 (has links) Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 4 uppsatser.

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