INVESTIGADORES
BRIAND Laura Estefania
artículos
Título:
Acylating Capacity of the Fosfotungstic Wells-Dawson Heteropoly-acid: Intermediate Reactive Species
Autor/es:
SEBASTIÁN E. COLLINS; SILVANA R. MATKOVIC; ADRIAN L. BONIVARDI; LAURA E. BRIAND
Revista:
JOURNAL OF PHYSICAL CHEMISTRY C
Editorial:
AMER CHEMICAL SOC
Referencias:
Año: 2011 vol. 115 p. 700 - 709
ISSN:
1932-7447
Resumen:
The mechanism of adsorption and decomposition of acetic anhydride over fosfotungstic Wells-Dawson heteropoly-acid (HPA)was investigated through infrared spectroscopy with especially dedicated in situ cells. Both gaseous and liquid acetic anhydride dissociatively chemisorbs on the heteropoly-acid producing the intermediate acyl species, adsorbed acetate species and acetic acid. The former is known as the key intermediate species in the Friedel Crafts acylation reaction. Moreover, the consumption of the Brønsted acid sites observed during the adsorption and decomposition of acetic anhydride over the HPA indicates that those places are the active sites of the genesis of the acyl intermediate species. Surface acetate species and acetic acid strongly adsorb on the active acid sites deactivating the heteropoly-acid.
