Synthesis of 2,2-difluoro-2H-chromenes through the tandem reaction of ethyl 3-bromo-3,3-difluoropropionate with salicylaldehyde derivatives

Ethyl 3-bromo-3,3-difluoropropionate underwent the reaction with salicylaldehyde derivatives in the presence of base at 110 °C in DMF to give the corresponding 2,2-difluoro-2H-chromenes in moderate to good yields.