One-Pot Conversion of N‑Allyl-α-cyano Esters to α‑Allyl-α-cyano Lactams through a Hydrolysis/Ketene Formation/Cyclization/Claisen Rearrangement Sequence
journal contributionposted on 12.02.2016, 00:00 by Mei-Hua Shen, Mei Han, Hua-Dong Xu
An intramolecular ketene aza-Claisen rearrangement is developed for the first time to enable the stereoselective synthesis of α-ally-α-cyano-lactams from N-allyl amino esters. This reaction also exhibits outstanding chemoselectivity when an unsymmetrical bis-N-allyl group is present in the starting molecule. The usefulness of this method is demonstrated by a short synthesis of optically active bicyclolactam from l-proline.