Abstract The reaction of o-phenylenediamine (4) with one, two or three equivalents of p- substituted 3-dimethylaminopropiophenone hydrochlorides 5a− e was studied. 4-Aryl-2, 3- dihydro-1H-1, 5-benzodiazepine derivatives 6a− e were obtained in good yields, along with the 1: 2-adducts 7c− e and the unexpected 1: 3-adducts rac-8c− e. The type of adduct formed is determined by the molar ratio of the reactants 4 and 5 and by the nature of the ...
