Palladium‐Catalyzed Ring‐Opening/Defluorinative Annulation of <i>gem</i> ‐Difluorocyclopropanes With <i>β</i> ‐Keto Sulfones: Synthesis of Multi‐Substituted Furans

A concise and efficient route to the synthesis of multi-substituted furans has been developed via Pd-catalyzed ring-opening/defluorinative annulation of gem-difluorocyclopropanes (gem-F₂CPs) with β-keto sulfones. Control experiments indicated that the reaction proceeds through a linear rather than a branched fluoroalkene intermediate, and further incorporates the C2 and C3 atoms of the gem-F₂CP motif into the furan skeletons selectively. Besides, the synthetic utility of this protocol was demonstrated through the modification of bioactive molecules and transformations of furan products into 1,4-epoxynaphthalene derivatives.