Ytterbium(III) Triflate–Catalyzed Stereoselective Synthesis of β‐Lactams via [2+2] Cyclocondensation in Ionic Liquid

Abstract

Catalyzed by ytterbium(III) triflate [Yb(OTf)₃], β‐lactams were stereoselectively synthesized from imines and acetyl chlorides in ionic liquid under mild conditions. The ionic liquid and catalyst could be recycled and reused as opposed to traditional solvent–catalyst systems.

Keywords:

• [2+2] Cyclocondensation
• ionic liquid
• β‐lactams
• ytterbium triflate

Acknowledgments

The authors are grateful to the National Basic Research Program (No. 2003CB114402) and National Natural Science Foundation of China (Nos. 20276072 and 20476098) for financial support.