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

2010; Elsevier BV; Volume: 378; Issue: 1 Linguagem: Inglês

10.1016/j.apcata.2010.02.011

1873-3875

Jorge Enrique Sambeth, Gustavo P. Romanelli, Juan C. Autino, Horacio J. Thomas, Graciela T. Baronetti,

Mesoporous Materials and Catalysis

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+.