Synthesis of 3,4-disubstituted 2(1H)-quinolinones via intramolecular Friedel–Crafts reaction of N-arylamides of Baylis–Hillman adducts

3,4-Disubstituted 2(1H)-quinolinones were synthesized starting from the Baylis–Hillman adducts via the following sequential processes: (i) hydrolysis of the Baylis–Hillman adduct to acid, (ii) EDC coupling with anilines, (iii) H2SO4-assisted intramolecular Friedel–Crafts cyclization, and the final (iv) DBU-mediated isomerization.