[3+3] Annulation Reaction of 2‐Amino‐4H‐chromen‐4‐ones with Cinnamaldehydes or Aromatic Aldehydes and Ethanal in One Pot: Access to 2‐Aryl‐5H‐Chromeno[2,3‐b]pyridin‐5‐ones

Abstract A formal [3+3] cascade annulation strategy for the synthesis of 2‐arylchromeno[2,3‐ b ]pyridinones has been developed using 2‐aminochromones and substituted cinnamaldehydes or aromatic aldehydes and ethanal as the substrates. The strategy supplies a novel and atom‐economical method of accessing a broad range of chromeno[2,3‐ b ]pyridine derivatives in good yields with good functional‐group tolerance. The method highlights the inherent practicality of this synthetic transformation.