Enantioselective Vinylogous Conia-Ene Reaction Catalyzed by a Disilver(I)/Bisdiamine Complex

Chiral all-carbon spirocycles emerge
in a wide variety of natural
products exhibiting biological and pharmacological activities. We
present the disilver­(I)/bisdiamine complex catalyzed asymmetric vinylogous
Conia-ene reaction of γ′-pentyne-cyclohex-3-enones for
the direct synthesis of chiral all-carbon spirocycles. The synergistic
catalysis of silver­(I) and the amine provided the vinylogous adducts
in good yields with high enantioselectivities. DFT calculations verified
the regioselectivity and enantioselectivity of the reaction and highlighted
the high catalytic activity of the disilver­(I)/bisdiamine complex.
In addition, various polycyclic products were achieved by derivatization
of the spirocyclic enones.