Zeolite Catalysts for Phenol Benzoylation with Benzoic Acid: Exploring the Synthesis of Hydroxybenzophenones

Catalysts

Gherardo Gliozzi²  Sauro Passeri²  Francesca Bortolani²  Mattia Ardizzi²  Patrizia Mangifesta²  Fabrizio Cavani¹ 

[1] Dipartimento di Chimica Industriale “Toso Montanari”, Viale Risorgimento 4, Università di Bologna, 40136 Bologna, Italy;

关键词: phenol;    benzoic acid;    hydroxybenzophenone;    H-beta;    benzoylation;    acylation;   

DOI  :  10.3390/catal5042223

来源: mdpi

【 摘 要 】

In this paper, we report on the reaction of phenol benzoylation with benzoic acid, which was carried out in the absence of solvent. The aim of this reaction is the synthesis of hydroxybenzophenones, which are important intermediates for the chemical industry. H-beta zeolites offered superior performance compared to H-Y, with a remarkably high conversion of phenol and high yields to the desired compounds, when using a stoichiometric amount of benzoic acid. It was found that the reaction mechanism did not include the intramolecular Fries rearrangement of the primary product phenyl benzoate, but indeed, the bimolecular reaction between phenyl benzoate and phenol mainly contributed to the formation of hydroxybenzophenones. The product distribution was greatly affected by the presence of Lewis-type acid sites in H-beta; it was suggested that the interaction between the aromatic ring and the electrophilic Al³⁺ species led to the preferred formation of o-hydroxybenzophenone, because of the decreased charge density on the C atom at the para position of the phenolic ring. H-Y zeolites were efficient than H-beta in phenyl benzoate transformation into hydroxybenzophenones.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.