Attempted synthesis of 1,4-benzodiazepine comprising an additional ring at the 1–3 position

Two possible synthetic routes leading to 1,4-benzodiazepine derivatives comprising an additional heterocyclic ring at position 1–3 have been studied. The first approach (scheme 1) consisted in subjecting intermediates VII and XII to the Bischler-Napieralski reaction while the second one (scheme 2) was based on intramolecular dehydration of amino ketone (XIX); both routes did however fail to yield the expected product XIII.