Some transformations of N-ethoxycarbonylmethylpyridinium bromides with a pyridyl or 1,4-dihydropyridyl substituent at position 3

Abstract

The direction of the reaction of derivatives of N-ethoxycarbonylmethylpyridinium bromide with chalcone in the presence of bases depends on the substituent at position 3 of the pyridine ring. In the presence of a pyridyl substituent a derivative of 2,3-dihydroindolizine is formed. In the case of a 1,4-dihydropyridyl substituent cycloaddition does not occur, and a Michael addition product (an acyclic betaine) is formed. The latter can be transformed into a derivative of indolizine only under the conditions of decarboxylation.

How to Cite
Makarova, N. V.; Plotnietse, A.; Tirzitis, G.; Turovskii, I.; Dubur, G. Chem. Heterocycl. Compd. 1997, 33, 175. [Khim. Geterotsikl. Soedin. 1997, 202.]

For this article in the English edition, see DOI https://doi.org/10.1007/BF02256759