Abstract

Mild liquid-phase friedel-crafts acylation of thiophene to 2-acetylthiophene over solid-acid catalysts

Author(s): WeiQuan,Yan Zhang, Dongpu Zhao, JianqiangYu

2-Acetylthiophene was synthesized by the acetylation of thiophene with acetic anhydride. Effects of solid-acid catalysts HZSM-5, NKC-9 and Hâ, reaction time and the molar ratio of acetic anhydride to thiophene were studied. Hâ showed excellent acetylation activity with almost 99% conversion of thiophene being obtained under conditions of normal pressure, reaction temperature 60ï‚°C and molar ratio of thiophene to acetic anhydride of 1:3. The yield of 2-acetyithiophene is 98.6%. The catalyst used can be recovered, regenerated and reused to give almost the same yield of 2-acetyithiophene as that given by the fresh Hâ zeolite.