Azepinones. IV. A synthetic route to some Dihydro- and Tetrahydro-1,3-diazepines

Abstract

lH-4,5,6,7-Tetrahydro-2-methyl-1,3-diazepine (1), 4H-1,5-dihydro-3-methyl- benzo[e]-[1,3]-diazepine (11), and 3H-4,5-dihydro-2-methylbenzo[d]-[1,3]-diazepine (IV) have been synthesized in good yields by treating suitably substituted 1,4- diaminobutanes with acetamidine hydrochloride under mild experimental conditions. This synthetic method may well be a general one for such compounds. When protonated, the compounds exist as amidinium salts, and the free bases (1) and (11) have basicities comparable to the 1,4,5,6,-tetrahydropyrimidines. I.r., N.M.R., and mass spectra data are reported for (1), (11), and (IV).