PREPARATIVE ASPECTS OF THE NITRATION OF 1-METHYLPYRROLE DERIVATIVES. 13C NMR OF SOME NITROPYRROLES.
The nitration of 1-methylpyrrole and 1,2-dimethylpyrrole was studied and the products were characterized. It was found that the nitration of ethyl 1-methylpyrrole-2-carboxylate depends on the reaction conditions. **1**3C parameters have been determined for several 1-methyl substituted pyrrole- and nitropyrrole derivatives and the relationship between the observed and predicted **1**3C shifts for aromatic carbons is briefly discussed. It has been found that the determination of the direct **1**3C-**1H coupling constants in the pyrrole ring constitutes a useful tool for distinguishing alpha - and beta -positions.