| Abstrakt: |
It is shown that a mixture of 7- and 8-substituted 2,3-dihydro-1,5-benzodiazepinones is formed in the reaction of unsymmetrical aromatic diamines (4-chloro-,4-methyl-, and 4-methoxy-o-phenylenediamines) with acetoacetic and benzoylacetic esters under severe conditions. The corresponding anilide of benzoylacetic acid, the cyclization of which again leads to a mixture of isomeric dehydrobenzodiazepinones, can be isolated (in the case of benzoylacetic ester) when the concentrations of the reacting substances and the reaction time are decreased; this makes it possible to assume amidation of the ?-keto acids as one of the steps in the high-temperature synthesis of dihydrobenzodiazepinones. The quantitative ratio of the isomers formed in the reaction was determined by UV spectroscopy. The UV, IR, and PMR spectral data are presented. |
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