1-Azabicyclic compounds. 24. Selectivity of position of nitration of 1,2-dihydropyrrolizine, 5,6,7,8-tetrahydropyrrocoline and pyrrole homologs

The selectivity of the position of nitration of 1-methylpyrrole, 1,2-dimethylpyrrole, 1,2-dihydropyrrolizine, and 5,6,7,8-tetrahydropyrrocoline was found. In contrast to the selectivity of substitution during nitration of their carbocyclic analogs, o-xylene, indane and tetraline, the fraction of the -nitro-isomer in the nitration products of 1,2-dimethylpyrrole is smaller than the fraction of -nitro derivatives of 1,2-dihydropyrrolizine and 5,6,7,8-tetrahydropyrrocoline, and in the two latter cases the isomers are almost equally distributed. During nitration of the above bicyclic pyrroles, the Mills-Nixon effect does not appreciably influence the selectivity of the position of the reaction.See 1] for Communication 23.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1489–1491, November, 1987.