Collect. Czech. Chem. Commun. 1989, 54, 1299-1305

Electrochemical oxidation of pyrrole derivatives in alcoholic medium

Farouk Tedjara, Salah Ymmela, Miroslav Jandab, Petr Duchekb, Petr Holýc and Ivan Stiborc

a Department of Electrochemistry, Setif University, Setif, Algeria
b Department of Organic Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6, Czechoslovakia
c Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6, Czechoslovakia


Electrochemical oxidation of pyrrole (I), 1-methylpyrrole (II), 1,2,5-trimethylpyrrole (III), methyl 1-methyl-2-pyrrolecarboxylate (IV) and diethyl 3,5-dimethyl-2,4-pyrroledicarboxylate (V) has been studied. An advantageous method of preparation of polypyrroles (PP) and conductive PVC-PP composites has been elaborated, permitting a 20 fold starting concentration of the monomer. Electrooxidation of II in methanol leads either to 5,5-dimethoxy-1-methyl-3-pyrrolin-2-one (VII) or 1-methyl-2,2,5,5-tetramethoxy-3-pyrroline (VI), their ratio depending on water content in the alcohol used. Oxidation of IV affords the analogous 5-carbomethoxy-5-methoxy-1-methyl-3-pyrrolin-2-one (X), oxidation of III and V leads to products of substitution at the methyl groups.