2//-Pyrrole 1-oxide, 2-cyano-2-methyl

In methanolic cyanide, N-substituted pyrroles193 are substituted in the 2-position by a cyano group on anodic oxidation. Methoxylation, which is often observed as a side reaction in the anodic oxidation in methanolic cyanide, was suppressed completely. When N-substituted pyrroles carry a methyl group in the 2- and 5-positions, a side-chain cyanation occurs.193,194... 

The H-NMR spectra (Table I) show no evidence of tautomerism of 1-hydroxypyrroles to 2H- or 3//-pyrrole 1-oxides and are similar to those of corresponding pyrroles. The hydroxyl proton is not always seen, as in the case of 1-hydroxyindole, and is easily exchanged out by deuterium oxide. The H-NMR spectrum of 2-cyano-2-methyl-2//-pyrrole 1-oxide (2) in dimethyl sulfoxide (DMSO) was unambiguous (Table I), but in deuter-iochloroform, the 3- and 4-protons appeared at the same position. 

A, 2-Cyano-2-methyl-2//-pyrrole 1-oxide B, Chromoxymycin see Section II, E. Exchanges in D20. c i-Bu. d Broad. 

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