Reactions of 4-chloro-1-nitrobenzene with o-substituted phenylacetonitriles; Synthesis of 8-chloro-1-methyl(and methylthiomethyl)-6-(2-substituted phenyl)-4H-s-triazolo[4,3-a]-1,4-benzodiazepines

Abstract

Reactions of 4-chloro-1-nitrobenzene with 2-methyl-, 2-methoxy- and 2-(methylthio)phenylacetonitrile in methanolic potassium hydroxide gave mixtures from which the expected 3-aryl-5-chloro-2,1-benzisoxazoles Ia-c were isolated in addition to the 2H-indoles IIIa and IIIc and acridines VIII and IX. The 2,1-benzisoxazoles were reduced to the 2-aminobenzophenones XIIa-c which were transformed via the phthalimidoacetamido compounds XIIIa-c to 5-aryl-7-chloro-1,3-dihydro-1,4-benzodiazepine-2-ones XVa-c. Treatment with phosphorus pentasulfide led to the thiones XVIa-c which reacted in boiling butanol either with acetohydrazide or with (methylthio)acetohydrazide to give the title compounds XVIIa-c and XVIIIa-c. They showed only weak anticonvulsant, incoordinating and central depressant effects.