INVESTIGADORES
PIZZIO Luis Rene
artículos
Título:
Tungstosilicate salts as catalysts in phenol tetrahydropyranylation and depyranylation
Autor/es:
ROMANELLI, G.P.,; AUTINO J.C.,; BLANCO M.N,; PIZZIO L.,R.
Revista:
APPLIED CATALYSIS A-GENERAL
Editorial:
Elsevier
Referencias:
Lugar: Amsterdam; Año: 2005 vol. 295 p. 209 - 215
ISSN:
0926-860X
Resumen:
The catalytic behavior of water-insoluble cesium or rubidium tungstosilicates was studied in phenol tetrahydropyranylation and depyranylation
reactions.
The salts were synthesized and characterized using Fourier transform infrared spectroscopy, BET surface area measurements, thermogravimetric
and differential thermal analysis and acidity evaluation by potentiometric titration with n-butylamine. Solids with high specific surface area,
high thermal stability, and undegraded Keggin structure of the anion were obtained. The cesium salts showed a higher acidity than the rubidium
salts.
Both reactions were carried out at room temperature, using toluene in the tetrahydropyranylation and methanol in the depyranylation as
solvents. It was observed that there is an influence of the acid strength of the different catalysts on the yields obtained in both reactions, although the
textural properties of the salts must also be taken into account. The cesium salts were more active than rubidium salts, the latter being only active in
the depyranylation reaction.n-butylamine. Solids with high specific surface area,
high thermal stability, and undegraded Keggin structure of the anion were obtained. The cesium salts showed a higher acidity than the rubidium
salts.
Both reactions were carried out at room temperature, using toluene in the tetrahydropyranylation and methanol in the depyranylation as
solvents. It was observed that there is an influence of the acid strength of the different catalysts on the yields obtained in both reactions, although the
textural properties of the salts must also be taken into account. The cesium salts were more active than rubidium salts, the latter being only active in
the depyranylation reaction.