First Total Synthesis of (+)-Podophyllic Aldehydes

• DOI: 10.1246/cl.141061
• Publication Date: 2014-12-11T00:11:41Z
• Authors: Junki Ito; Daichi Sakuma; Yoshinori Nishii
• Keywords: 01 natural sciences; 0104 chemical sciences

Abstract The first total synthesis of three (+)-podophyllic aldehydes was achieved in a highly enantiocontrolled manner. Key steps include the organocatalyzed highly enantioselective cyclopropanation and Lewis acid-mediated chiral transfer ring expansion with excellent level of stereoinduction. This method can alternatively provide (+)- and (−)-podophyllic aldehydes by switching the organocatalyst in the asymmetric cyclopropanation.