Iranian Journal of Chemistry & Chemical Engineering (Jun 1999)
"One Pot" Synthesis of 1,5-Diaza-2,3,6,7-Thetrahydro-4-Methyl-Phenanthrene-4,8-Dione From Corresponding Bis-Beta-Amino Acid
Abstract
The cyclization of b-anilino propionic acids in the presence of polyphosphoric acid (PPA) afforded the 2,3-Dihydroquinoline-4-(1H)-ones in good yields. N,N'-bis(2-carboxyethyl)-4-methyl-1,2-diaminobenzene (7) is cyclized under this condition to produce the 1,5-diaza-2,3,6,7-tetrahydro-4-methyl-pheranthrene-4,8-dione(bis-quinolone) (8).