Opening of the ring of five-membered aromatic heterocycles under the influence of bases (review)

The review is devoted to a discussion of the various mechanisms of dehydration of five-membered aromatic heterocycles under the influence of bases; this reaction can be used in many cases for the synthesis of hard-to-obtain polyunsaturated acyclic compounds.Part of the material in this review was presented in a lecture given by S. Gronowitz at Moscow State University on May 31, 1976.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 435–451, April, 1978.