Studies on the synthesis of heterocyclic compounds. Part VIII. A facile synthesis of new pyrazolo[3,4-b]benzazepine-4,9-diones

2-Carbomethoxybenzoyl chloride reacted with some 5-methylamino-l-phenyl-3-R-pyrazoles to yield N-methyl-l-phenyl-3-R-pyrazol-5-yl)-2-carbomethoxybenzamides. These products were readily transformed into the corresponding acid, which in turn, refluxed in phosphorus oxychloride afforded the tricyclic system, l-phenyl-3-R-pyrazolo[3,4-b]benzazepine-4,9-dione.