A new vapour phase process to produce 2-hydroxyphenylalkylketones

A new environmentally friendly synthesis of hydroxyphenylalkylketones was developed operating in vapour phase and using commercial solid acid catalysts. The role of the reaction conditions and the behaviour of different solid acid catalysts were first investigated and correlated to the catalyst features. High conversion values of the phenylacetate feed and high selectivity in the orto-hydroxyacetophenone, together with a low amount of by-products, were obtained using a commercial pentasil-type zeolite. The features of this catalyst as such or in the presence of finely ground SiO2 or Al2O3 as binder are discussed with a view to explaining its unusual behaviour. In addition, good catalytic performances were also obtained with longer chain esters.