Resumo

MENDOZA, Jorge A.; GARCIA-PEREZ, Enrique; JIMENEZ-VAZQUEZ, Hugo A.  e  TAMARIZ, Joaquín. Effect of Aryl Substituents on the Reactivity of the Captodative Olefins 1-Acetylvinyl Arenecarboxylates. J. Mex. Chem. Soc [online]. 2006, vol.50, n.2, pp.47-56. ISSN 1870-249X.

With the aim of evaluating the effect of substitution at the aryl moiety of the aroyloxy group of captodative olefins 1 on their reactivity in Diels-Alder and other reactions, the new series of olefins 1-acetylvinyl arenecarboxylates 1c-1k were prepared. No correlation was found between ¹³C NMR chemical shifts of the carbon atoms of the double bond and the electronic effects of the diverse substituents. However, an excellent correlation was observed between the energies of the FMOs (HF/6-31G*), or the corresponding atomic coefficients or the Mülliken charges at the carbon atoms of the double bond, and the Hammett σ_m and σ_p constants of the phenyl ring substituents of some members of the series, and of some other calculated analogues. These results strongly suggest that, in addition to the major effect of the electron-withdrawing group, the reactivity of captodative olefins 1 is also controlled by the long-range inductive effects of the sub­stituent at the phenyl ring of the aroyloxy group.

Palavras-chave : Captodative olefins; 1-acetylvinyl arenecarboxylates; FMO; Hammett constants; inductive effects.

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