New Captodative Olefins: 3-(2-Furoyloxy)-3-buten-2-one and Alkyl 2-(2-Furoyloxy)-2-propenoates, and their Reactivity in Addition Reactions
A new series de captodative olefins 3-(2-furoyloxy)-3-buten-2-one and alkyl 2-(2-furoyloxy)-2-propenoates, 3a-3c, hasbeen prepared with the aim of evaluating the effect of a heterocyclein the electron-donating moiety on the reactivity of these compoundsin Diels-Alder and conjugate additions. In the...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2007 |
| País: | México |
| Institución: | Universidad Michoacana de San Nicolás de Hidalgo |
| Repositorio: | Redalyc-UMSNH |
| OAI Identifier: | oai:redalyc.org:47551406 |
| Acceso en línea: | https://www.redalyc.org/articulo.oa?id=47551406 |
| Access Level: | acceso abierto |
| Palabra clave: | Química FMO Diels Alder Crafts Friedel |
| Sumario: | A new series de captodative olefins 3-(2-furoyloxy)-3-buten-2-one and alkyl 2-(2-furoyloxy)-2-propenoates, 3a-3c, hasbeen prepared with the aim of evaluating the effect of a heterocyclein the electron-donating moiety on the reactivity of these compoundsin Diels-Alder and conjugate additions. In the former reactions, theirbehavior has been evaluated by reacting under thermal and catalyzedconditions with cyclopentadiene (9) and cyclohexadiene (12) as thedienes, showing a comparable reactivity, but a lower stereoselectivity,with respect to the reference captodative olefins 1a and 2a. Inthe case of conjugate additions, the Friedel-Crafts reaction of thehighly activated benzene ring of 1,2,4-trimethoxybenzene (7) led tothe corresponding adduct 8 only for olefin 3a. Ab initio calculations(HF/6-31G*) of the energies and coefficients of the FMOs were carriedout to explain the experimental reactivity in both processes. Theresults suggest that both the electron-withdrawing and the 2-furoyloxygroups are involved in controlling the reactivity and selectivityof olefins 3. |
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