<Benzo-[f]-indole>-4,9-dione derivatives were prepared from $2-chloro-3-({alpha}-accetyl-{alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ and 2-chloro-3-N-phenylamino-1,4-naphthoquinone. $2-Chloro-3-({alpha}-acetyl-{alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ was reacted with amines to give $2-amino-3-({alpha}-acetyl-{alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ derivatives. Subsequent treatment of $2-amino-3-({alpha}-acetyl-{alpha}-ethoxycarbonyl-methyl)-1,4-naphthoquinone$ with sodium ethoxide gave <benzo-[f]indole>-4,9-dione derivatives. When 2-chloro-3-N-phenylamino-1,4-naphthoquinone reacted with sodium ${alpha}-cyano$ ethyl acetate, 2-amino-3-ethoxycarbonyl-N-phenyl-<Benzo-[f]-indole>-4,9-dione was obtained. However, with sodium diethyl malonate, not <benzo-[f]-indole>-4,9-dione but 2-chloro-3-bis-(methoxycarbonyl)-methyl-2H-3-N-phenylamino-1,4-naphthoquinone was obtained.