Research Article
Ultrasound-Assisted Wittig Reaction for the Synthesis of 3-Substituted 4-Chloroquinolines and Quinolin-4(1H)-ones with Extended π-Conjugated Systems
Scheme 3
Diels–Alder reaction of 3-vinyl-4-quinolones 7a, b with N-methylmaleimide 9 to give novel acridones 11a, b.