Pyridinium triflate catalyzed intramolecular alkyne-carbonyl metathesis reaction of O-propargylated 2-hydroxyarylaldehydes

Abstract

3,5-Dibromopridinium trifluoromethanesulfonate catalyzes the intramolecular alkyne-carbonyl metathesis reaction of a variety of O-propargylated 2-hydroxyarylaldehydes and ketones bearing alkyl, aryl and heteroaryl substituted internal alkynes to provide various 3-(hetero)aroyl 2H-chromenes in high yields. © 2020 Elsevier Ltd