Facile Synthesis of 9-Acetyl/Formyl/Cyano-Substituted Pyrano[2,3-f]flavones and Chromones Using the Baylis–Hillman Reaction

Abstract

Condensation of 8-formyl-7-hydroxyflavones (2a–f) and 8-formyl-7-hydroxy-2-(2′-furyl)-3-methylchromone (2g) with methyl vinyl ketone (3), acrolein (4), and acrylonitrile (5) in the presence of diazabicyclo[2.2.2]octane (DABCO) under an N₂ atmosphere at room temperature using Baylis–Hillman reaction conditions afforded 9-acetyl/formyl/cyano-substituted pyrano2,3-f]flavones (6a–f, 7a–f, 8a–f) and chromones (6g, 7g, 8g).

Keywords:

• Acrolein
• acrylonitrile
• DABCO
• 8-formyl-7-hydroxyflavones
• ketone
• methyl vinyl

ACKNOWLEDGMENTS

One of the authors (S. S. R.) thanks the Council for Scientific and Industrial Research, New Delhi, India, for financial support and grants of junior and senior research fellowships. Our sincere thanks go to the director of the Indian Institute of Chemical Technology (IICT), Hyderabad, India, for providing spectral data and library facilities.