The structures of the 2-and 4-methylpyridines have not been definitely determined and one finds both the pyridine and pyridone-methide structures used for 2-methylpyridine. Tschitschibabinl postulated that both the 2-and 4-isomers existed as tautomeric mixtures of the two forms. Cart-Wright and Errera* presented evidence based on infrared absorption spectral curves of the 2-and 3-methylpyridines which indicated the existence of only the ...
