A general procedure for the preparation of 4-substituted-3-halo-2-quinolones (halo= F, Cl, Br) utilizing 2-halo diethylphosphonoacetic acids (halo= F, Cl, Br) and o- aminophenylketones as the starting materials is described. The title compounds are obtained by an intramolecular Horner–Wadsworth–Emmons olefination of halogen- containing N-acyl-o-aminophenylketones. The transformation process is generally ...
