INFIQC 05475
INSTITUTO DE INVESTIGACIONES EN FISICO- QUIMICA DE CORDOBA
Unidad Ejecutora - UE
artículos
Título:
Steric effects of nucleophile-radical coupling reaction. Determination of rate constants for the reaction of aryl radicals with 2-naphthoxide anion
Autor/es:
TOMÁS C. TEMPESTI; ADRIANA B. PIERINI; MARÍA T. BAUMGARTNER*
Revista:
NEW JOURNAL OF CHEMISTRY
Editorial:
Royal Society of Chemistry
Referencias:
Año: 2009 vol. 33 p. 1523 - 1528
ISSN:
1144-0546
Resumen:
The absolute rate constants for the reaction of different aryl radicals with 2-naphthoxide anion were determined using an indirect method, a competition of the coupling reaction with the H-atom abstraction. We here show that the radical-ambident nucleophile reactions are sensitive to steric hindrance. A lower reactivity is found for 2-anisyl radical with respect to 4-anisyl and for 2-methoxy-1-naphthyl radical with respect to 1-naphthyl (k2b o k2a and k2d o k2c). The ortho substitution to the radical centre decreases the rate constant. The reactivity is in agreement with energy barriers determined by theoretical calculations.
