The palladium-catalyzed and CsF-promoted annulation reaction of bromoalkynes and isocyanides regioselectively affords a diverse set of 5-iminopyrrolone derivatives. This chemistry presumably proceeds through the bromoacrylamide intermediates, which can be readily prepared from the nucleophilic addition reaction of isocyanides to bromoalkynes in the presence of CsF.
Herein, we report a straightforward method to access alkenyl dihydrofurans via palladium-catalyzed acetalization/annulation from conjugated enynones and alcohols. The reaction undergoes a 5-exo-dig cyclization process, with the formation of four new chemical bonds including two carbon–halogen bonds on the exocyclic alkenyl moiety. Preliminary mechanistic studies suggest that the haloalkyne generated