The catalytic activity and reusability of the metallic Lewis acids, Cu(OTf)2, Yb(OTf)3, Sc(OTf)3, In(OTf)3, HfCl4·(THF)2 and InCl3, for acetylation of alcohols with acetic anhydride and acetic acid has been examined in environmentally benign room temperature ionic liquids, [bmim][X] (bmim = 1-n-butyl-3-methylimidazolium, X = PF6, BF4, SbF6). All of the catalysts effectively catalyzed the acetylation with acetic anhydride in an ionic liquid, [bmim][PF6]. In direct acetylation with acetic acid, Yb(OTf)3, Sc(OTf)3 and InCl3 showed excellent catalytic activity in the [bmim][PF6] ionic liquid and were reasonably recycled.
Bibliographical noteFunding Information:
The National Laboratory Program from MOST, the Center for Molecular Design and Synthesis (CMDS) at KAIST, the Korea National Center for Cleaner Production and KIST are supported this work.
- Ionic liquids
- Lewis acids