Tandem Double-Michael-Addition/Cyclization/Acyl Migration of 1,4-Dien-3-ones and Ethyl Isocyanoacetate: Stereoselective Synthesis of Pyrrolizidines

✍ Scribed by Jing Tan; Xianxiu Xu; Lingjuan Zhang; Yifei Li; Qun Liu

• Publisher: John Wiley and Sons
• Year: 2009
• Tongue: English
• Weight: 611 KB
• Volume: 48
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.200805703

✦ Synopsis

Abstract

Up to four adjacent stereocenters can be formed stereoselectively in the construction of a pyrrolizidine unit through a novel organocatalytic reaction that involves treatment of various dienones with ethyl isocyanoacetate (see scheme; DBU=1,8‐diazabicyclo[5.4.0]undec‐7‐ene). Mechanisms for this atom‐economic, one‐pot synthesis have been proposed.magnified image