Abstract
1,2,4-Triazino[1,2-b]phthalazine-6,11-dione (3) and 1,2,4-triazino[1,2-b]phthalazine-5,10-dione (4) were prepared via the reaction of 2-aminothiocarbonylphthalazine-1,4-dione with ethyl chloropropionate and ethyl chloroacetate. Acetylation of 4 with Ac2O gave the corresponding monoacetyl derivative (5), while the acetylation of 4 with Ac2O in the presence of AcONa gave the corresponding diacetyl derivative (6). Treatment of 4 with bromine in AcOH and aromatic aldehydes afforded the corresponding 3-substituted-1,2,4-triazino[1,2-b]phthalazine-5,10-diones (7 and 8). The electron impact mass spectra of both of the above series of compounds have also been recorded and their fragmentation pattern is discussed.