Reactions of heterocyclic quinone methides: 1-Methyl-3-methylene-2,4(1H,3H)-quinolinedione

Article abstract of DOI:10.1055/s-1990-27077

1-Methyl-3-methylene-2,4(1H,3H)-quinolinedione (2), prepared from 4-hydroxy-1,3-dimethyl-2(1H)-quinolinone (1) and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) gives the dimer 3. Compound 2 also reacts in situ with 2,2-dimethyl-2H-1-benzopyran and with isopropenyl acetate to give Diels-Alder cycloaddition products.