Enantioselective Synthesis of Dihydropyridione-Fused Uracils by N-Heterocyclic Carbene Organocatalysis.

A highly enantioselective synthesis of dihydropyridone-fused uracils has been disclosed by NHC-catalyzed formal (3 + 3) annulation of 6-amino uracil with α,β-unsaturated acylazoliums. Most target compounds are obtained in high yields with high to excellent enantioselectivity. Moreover, the developed protocol has the advantages of mild conditions, broad substrate scope, and ease of late-stage modification. The obtained chiral dihydropyridone-fused uracil scaffolds may be potentially useful in the discovery of lead compounds in medicinal chemistry.