Conjugated azoalkenes. Part 8. Reaction of some conjugated azoalkenes with activated nitriles. Synthesis of new pyrrolo[2,3-b]pyrroles and 1,2-diaminopyrroles. X-Ray molecular structure of diethyl 6-amino-1,6-bis-(t-butoxycarbonylamino)-3a-cyano-2,5-dimethyl-1,3a,6,6a-tetrahydropyrrolo-[2,3-b]pyrrole-3,4-dicarboxylate

Abstract

The reactions of some conjugated azoalkenes with nitriles containing active methylene groups have been studied and, depending on the nature and the molar ratios of the reagents, new 1,2-diamino-3-cyanopyrroles, and symmetric and asymmetric 1,3a, 6,6a-tetrahydropyrrolo[2,3-b]pyrroles can be obtained in good yields and under mild reaction conditions. The stereochemistry of one of the 1,3a,6,6a-tetrahydropyrrolo[2,3-b]pyrrole derivatives was investigated in detail by X-ray diffraction.