Synthesis of Potentially Bioactive Heterocycles: Thermal [3,3]Sigmatropic Rearrangement of 4‐(4′‐Aryloxybut‐2′‐ynyloxy)‐6‐methyl‐2‐pyridone

Abstract

Synthesis of a number of hitherto unreported 4‐aryloxymethylene‐7‐methyl‐2,3‐dihydropyrano[3,2‐c]pyridine‐5‐ones 4a–h have been achieved in moderate yields by the thermal [3,3]sigmatropic rearrangement of 4‐(4′‐aryloxybut‐2′‐ynyloxy)‐6‐methyl‐2‐pyridone.

Keywords:

• 1‐Aryloxy‐4‐chlorobut‐2‐yne
• exocyclic olefin
• heterocycles
• 4‐hydroxy‐2‐pyridone
• [3,3]sigmatropic rearrangement

Acknowledgment

We thank the CSIR (New Delhi) for financial support and one of us (H. R.) is grateful to the University of Kalyani for a fellowship.