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SO3H-functionalized ionic liquid catalyzed alkylation of catechol with tert-butyl alcohol / Xiaowa Nie in Industrial & engineering chemistry research, Vol. 49 N° 17 (Septembre 1, 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 17 (Septembre 1, 2010) . - pp 8157–8163 Titre : SO3H-functionalized ionic liquid catalyzed alkylation of catechol with tert-butyl alcohol Type de document : texte imprimé Auteurs : Xiaowa Nie, Auteur ; Xin Liu, Auteur ; Lei Gao, Auteur Année de publication : 2010 Article en page(s) : pp 8157–8163 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Ionic  liquid  Tert  butyl  alcohol. Résumé : Several SO3H-functionalized ionic liquids (FILs) were synthesized and their catalytic performances for catechol (CAT) alkylation with tert-butyl alcohol (TBA) were studied theoretically as well as experimentally. Under optimized reaction conditions, the conversion of CAT was 41.5%, and the selectivity for 4-tert-butyl catechol (4-TBC) could reach 97.1%. This electrophilic reaction exhibits a kinetics-dependent character. The higher frontier electron density at the C4 site, comparatively lower activation energy barrier (Ea), and higher thermodynamic stability all act in concert to make the reaction proceed preferentially toward 4-TBC. The FILs can lead to a much higher CAT conversion and a similar selectivity to 4-TBC compared to a Beta zeolite catalyst. Because the frontier electron density [fr(E)] of CAT was not significantly affected by the solvent, the product selectivity rule would not vary, whereas the addition of a solvent with a higher dielectric constant would slow the reaction by increasing Ea, thus resulting in a lower CAT conversion. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100800c [article] SO3H-functionalized ionic liquid catalyzed alkylation of catechol with tert-butyl alcohol [texte imprimé] / Xiaowa Nie, Auteur ; Xin Liu, Auteur ; Lei Gao, Auteur . - 2010 . - pp 8157–8163. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 17 (Septembre 1, 2010) . - pp 8157–8163 Mots-clés : Ionic  liquid  Tert  butyl  alcohol. Résumé : Several SO3H-functionalized ionic liquids (FILs) were synthesized and their catalytic performances for catechol (CAT) alkylation with tert-butyl alcohol (TBA) were studied theoretically as well as experimentally. Under optimized reaction conditions, the conversion of CAT was 41.5%, and the selectivity for 4-tert-butyl catechol (4-TBC) could reach 97.1%. This electrophilic reaction exhibits a kinetics-dependent character. The higher frontier electron density at the C4 site, comparatively lower activation energy barrier (Ea), and higher thermodynamic stability all act in concert to make the reaction proceed preferentially toward 4-TBC. The FILs can lead to a much higher CAT conversion and a similar selectivity to 4-TBC compared to a Beta zeolite catalyst. Because the frontier electron density [fr(E)] of CAT was not significantly affected by the solvent, the product selectivity rule would not vary, whereas the addition of a solvent with a higher dielectric constant would slow the reaction by increasing Ea, thus resulting in a lower CAT conversion. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100800c