Enantioselective N‐Heterocyclic Carbene‐Catalyzed Synthesis of Saccharine‐Derived Dihydropyridinones with cis‐Selectivity.

The enantioselective N-heterocyclic carbene-catalyzed [2 + 4] cyclocondensation of α-chloroaldehydes and saccharine-derived 1-azadienes was developed, giving the corresponding saccharine-derived dihydropyridinones in good yields with exclusive cis-selectivities and excellent enantioselectivities.