A theoretical–experimental study of Wells-Dawson phospho-tungstic heteropolyacid: An explanation of the pseudoliquid or surface-type behaviour

JORGE E. SAMBETH; GUSTAVO P. ROMANELLI; JUAN C. AUTINO; HORACIO J. THOMAS; GRACIELA T. BARONETTI

APPLIED CATALYSIS A-GENERAL

ELSEVIER SCIENCE BV

Año: 2010 vol. 378 p. 114 - 118

0926-860X

The aim of the present work is to predict theoretically the nature of the mechanism of catalytic behaviour, pseudoliquid or surface-type, of Wells-Dawson solid acid (WDA). For this purpose, we took into account the dipolar moment of the substrates and the presence of H5O2 + species in their structure, considering both theoretical and experimental results. In the present paper we studied experimentally the deprotection reaction of aldehydes from 1,1-diacetates. These theoretical and experimental results together with our previous works indicate that the catalytic behaviour of WDA is a function of the dipolar moment of organic molecules and the presence of H5O2 + species. The pseudoliquid or surface-type behaviour depends on the physicochemical properties of the organic structure and its possibility of interaction with H5O2+.