Collect. Czech. Chem. Commun. 1984, 49, 543-548

Oxidation of 1,2,3,4,6-substituted pyridinium salts with ferricyanide

Petr Nesvadba and Josef Kuthan

Department of Organic Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6


Quaternary pyridinium salts IIa-IId are oxidized with alkaline solution of potassium ferricyanide to give a mixture of pyrrole derivatives Ia-Ib and IVa-IVd. The quaternary salt IIe under the same conditions affords a mixture of compounds IVe and V whereas IId gives only the pyrrole derivative IVd. The reaction mechanism is discussed and spectral characteristics of the products are interpreted.