Base-Promoted [4+2] Annulation Reaction of In Situ-Generated Azadienes from N-Propargylamines with Active Methylene Compounds: Access to Highly Functionalized 2-Pyridones

A facile and efficient synthesis of structurally diversified 2-pyridones is demonstrated using the [4 + 2] annulation of in situ generated azadienes from N-propargylamines and active methylene compounds. The reaction is promoted by an inorganic base giving moderate to good yields. The developed methodology is applicable for the direct and formal synthesis of various bioactive molecules. The synthetic utility of the protocol was also illustrated by late-stage functionalization of the products.

Automated summary

A facile and efficient method for the synthesis of structurally diversified 2-pyridones using the [4 + 2] annulation of in situ generated azadienes from N-propargylamines and active methylene compounds is demonstrated. The reaction, promoted by an inorganic base, provides moderate to good yields. The developed methodology is applicable for the direct and formal synthesis of various bioactive molecules, with the synthetic utility further illustrated by late-stage functionalization of the products.