One-pot synthesis of optically enriched 2-piperidinones from aliphatic aldehydes and cyanoacrylamides
Ying He1, Tai-Ran Kang, Quan-Zhong Liu
1Chemical Synthesis and Pollution Control Key Laboratory of Sichuan Province, College of Chemistry and Chemical Engineering, China West Normal University, Nanchong, 637009, China.
Abstract:
A highly stereoselective one-pot reaction of aliphatic aldehydes and cyanoacrylamides has been developed. The one-pot reaction includes an organocatalytic Michael addition followed by an intramolecular hemiaminalization. After reduction, optically enriched 2-piperidinones with three contiguous chiral centers were obtained in up to 95% yield and 9:1 dr with 99% ee.
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