An unprecedented methylene oxidation accompanying the aza Diels–Alder reactions of acyclic unactivated alkenes: synthesis of novel quinolin-3-one substituted pyrimidinone derivatives

The regioselective aza Diels–Alder reactions of isopropenyl pyrimidinone with N-arylimines in the presence of Y/Sc triflates as catalyst are described. An unprecedented oxidation of methylene to carbonyl occurred resulting in exclusive formation of 6-oxo-1,6-dihydropyrimidin-5-yl-4H-quinolin-3-one derivatives.