Novelties of synthesis of acetoveratrone using heteropoly acid supported on hexagonal mesoporous silica

Abstract

Friedel–Crafts acylations are often used for synthesis of important aromatic ketones such as acetoveratrone, which is the intermediate for synthesis of papavarine alkaloids. This is produced by conventional homogeneous catalysts and HY and Hβ zeolites which are known to deactivate. The current study reports the development of environmentally benign route for acetoveratrone synthesis. Twenty percent dodecatungstophosphoric acid supported on hexagonal mesoporous silica (DTP/HMS) was synthesized. This catalyst was found to be very active and also stable without any deactivation. The catalyst was characterised for its ultrastructural features by using X-ray diffraction, SEM, framework IR and nitrogen sorption techniques. Based on the experimental data a suitable mathematical model is proposed to describe the reaction kinetics. It was possible to determine the adsorption equilibrium constant and reaction rate constant from the same set of data and the reaction follows the Eley Rideal mechanism. The results are novel.