Pyrroles from ketoximes and acetylene

On the basis of a comparative study and analysis of the chemical shifts in the ¹³C NMR spectra of 1-vinyl-2-arylpyrroles and 3-alkyl-1-vinyl-2-phenylpyrroles, as well as 2-phenyl- and 1-ethyl-2-phenylpyrroles, it was established that the effects of substituents in the investigated series are transmitted via a mechanism involving conjugation and induction; the conductivity and polarizability of the 2-arylpyrrole system increase when a vinyl group is introduced in the 1 position or, in the case of the 1-vinylpyrrole system, when a phenyl group is introduced in the 2 position; this is due to the increase in the degree of overall conjugation.See 1] for communication IV.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 768–772, June, 1978.