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