A Straightforward Selective Acylation of Phenols over ZSM-5 towards Making Paracetamol Precursors

Robby Roswanda (Organic Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jalan Ganesha 10, Bandung 40132)
Alfhons Daniel Sirampun (Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jalan Ganesha 10, Bandung 40132)
Rino Rakhmata Mukti (Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jalan Ganesha 10, Bandung 40132)
Didin Mujahidin (Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, Jalan Ganesha 10, Bandung 40132)

Bulletin of Chemical Reaction Engineering & Catalysis
2018: BCREC Volume 13 Issue 3 Year 2018 (December 2018)

Commercially available ZSM-5 was minimally treated as the catalyst to selectively acylate phenols. The ZSM-5 was simply immersed in ammonium nitrate in order to fill the pores with Brönsted acid to concentrate the catalytic reactions inside the pores. The reactions were carried out in liquid phase at 383 K. Acetic acid and propionic acid were chosen as the acyl substrate. Gas chromatography reveals two products which are phenyl acetate and almost exclusively para-hydroxyacetophenone meaning no ortho product observed. This para selectivity can be attributed to the pores of ZSM-5 where the reaction is assumed to be happening via intermolecular reaction. It is a relatively straightforward method in making para-hydroxyacetophenone which is known as paracetamol precursor.