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Three-component reactions of tetrahydropyrrolo[1,2-a][1,4]benzodiazepines with methyl propiolate or acetylacetylene and СН, NH, SH, and ОН acids were studied in various solvents. The reaction direction is assumed to depend on the nucleophilicity of anion, formed through deprotonation of acid by the anionic center of initial Michael-type zwitterion.

The three-component reaction of 4-phenyl-, p-methoxyphenyl-, and thienylpyrrolo[1,2-a][1,4]benzo-diazepines with methyl propiolate and indole in dichloromethane proceeds through opening of the diazepine ring. The major transformation products isolated are substituted pyrroles, namely, 1-(2-aminomethylphenyl)-5-(arylmethyl)-2-(indol-1(3)-yl)pyrroles and 1-(2-aminomethylphenyl)-2-aryl-(indol-3-yl)-methylpyrroles.

It has been established that the reaction of pyrrolo[1,2-a][1,4]benzodiazepines with activated alkynes gives pyrrolo[1,2-a][1,6]benzodiazonines as the products of diazepine ring expansion. In the case of pyrrolo[1,2-a][1,4]benzodiazepine, substituted with formyl group at the pyrrole ring, both expansion and cleavage of the diazepine fragment can occur.

Fused benzodiazepines were found to react with activated alkynes to effect either vinylation of unsubstituted nitrogen atom or dealkylation of nitrogen and its further vinylation. For benzodiazepinones bearing lactam fragment, the reactions with alkynes proceed by several pathways: formation of vinyl-substituted benzodiazepines, the Stevens rearangement products, and expansion of the diazepine ring: benzodiazonine and diazecine.

Reaction of pyrrolobenzodiazepines (I) with activated alkynes gives pyrrolo[1,2-a][1,6]benzodiazonines as products of a diazepine ring expansion.