Quinazolines and 1,4-benzodiazepines. Part XXIX. Synthesis of some 2,3-dihydro-5-pyridyl-1H-1,4-benzodiazepines

Syntheses of the three isomeric 2,3-dihydro-7-nitro-5-(2-, 3-, and 4-pyridyl)-1H-1,4-benzodiazepines from the corresponding (2-chloro-5-nitrobenzoyl)pyridines and ethylenediamine are described. The required benzoyl-pyridines were made by nitration of the appropriate (2-chlorobenzoyl)pyridines, the preparations of which are given. The 7-nitrobenzodiazepines were converted, by reduction of the nitro-group followed by the Sandmeyer reaction, into the corresponding psychopharmacologically active 7-chloro-derivatives.