Merging Alkene Isomerization Enables Difunctionalization of Cyclic Enamines toward Ring-Fused Aminal Synthesis.

Here we report a Pd-catalyzed isomerization of alicyclic allyl amine to achieve the unprecedented α,β-difunctionalization of synthetically inaccessible trisubstituted cyclic enamine. The dual role of in situ formed enamine intermediate allows for the intermolecular formal [4 + 2] reaction with acrylamide or isatoic anhydride to simultaneously construct the C-C bond and C-N bond, thus realizing the expedient construction of [4.3.0]-aminal with excellent diastereoselectivity and high atom economy.