Novel methods of synthesizing naphtho[1,2-c]furan-1,3-dione and benzo[e]isoindole-1,3-dione

Convenient methods of synthesizing naphtho[1,2-c]furan-1,3-dione and benzo[e]isoindole-1,3-dione from phenylbutyric acid derivatives have been established. Naphtho[1,2-c]furan-1,3-dione and benzo[e]isoindole-1,3-dione were obtained respectively from 4,5-dihydronaphtho[1,2-c]furan-1,3-dione and 4,5-dihydrobenzo[e]isoindole-1,3-dione by aromatization with 10% Pd-C in AcOH under mild conditions. In addition, benzo[e]isoindole-1,3-dione derivatives were obtained from 4,5-dihydronaphtho [ 1,2-c] furan-1,3 -dione by imidation and simultaneous aromatization with primary amine in AcOH in one pot.