Novel synthesis of tetrahydro-2(1H)-quinolones using Diels–Alder reactions of 1-arylsulfonyl-2(1H)-pyridones having an electron-withdrawing group

A novel synthetic methodology of preparing tetrahydro-2(1H)-quinolones by Diels–Alder reactions between 2-methyl- and 2,3-dimethyl-1,3-butadienes and 1-arylsulfonyl-2(1H)-pyridones having an electron-withdrawing group at the 5-position is presented. Furthermore, the site-selectivity analyses based on MO calculations of the 5-substituted 2(1H)-pyridones acting as the dienophiles are described.