Palladium-catalyzed acetalization/cyclization of enynones with alcohols: rapid access to functionalized dihaloalkenyl dihydrofurans†
Abstract
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 in situ should be involved in this transformation.