Synthesis of 3-substituted 4-hydroxyquinolin-2-ones via C-acylation reactions of active methylene compounds with functionalized 3,1-benzoxazin-4- ones

Article abstract of DOI:10.3987/com-99-8508

A general protocol for the construction of 4-hydroxyquinolin-2-ones is described. Benzoxazinones react with the anion of active methylene compounds to produce the functionalized C-acylation compounds in very good yields. These key intermediates are cyclized to the desired quinolinones (25-40) under basic conditions. Spectral data and physical characteristics for all compounds are reported.