A Benzannulation Strategy for Rapid Access to Quinazoline-2,4-diones via Oxidative N-Heterocyclic Carbene Catalysis
Arghya Ghosh, Sayan Shee, Akkattu T. Biju
Abstract
N-Heterocyclic carbene-catalyzed formal [4+2] benzannulation of enals with suitably substituted pyrimidine-2,4-diones allowing the mild and facile synthesis of functionalized quinazoline-2,4-diones is presented. This oxidative transformation proceeds via the simultaneous generation of dienolates and α,β-unsaturated acylazoliums and follows a vinylogous Michael/aldol/β-lactonization/decarboxylation/oxidation sequence to afford quinazoline-2,4-diones, including axially chiral ones with suitable substitutions, in an operationally simple procedure. In addition, substituted coumarins as dienolate precursors afforded benzochromen-6-one derivatives.
Topics & Concepts
ChemistryCarbeneQuinazolineCatalysisAldol reactionCombinatorial chemistryOxidative decarboxylationPyrimidineDecarboxylationOxidative phosphorylationOrganic chemistryMedicinal chemistryStereochemistryBiochemistryN-Heterocyclic Carbenes in Organic and Inorganic ChemistryQuinazolinone synthesis and applicationsSynthetic Organic Chemistry Methods