4,5‐Dimethylimidazole: A correction and alternative synthesis

Fractional vacuum distillation of the product obtained from thermal condensation of acetoin with formamide is a formic acid complex of 4,5‐dimethylimidazole, and not the expected free base. The 1 H and 13 C nmr spectra suggest that the product may be closer to a 1:1 hydrogen‐bonded adduct than to a true salt. Commercial 4‐hydroxymethyl‐5‐methylimidazole is converted quantitatively to the 4‐chloromethyl derivative with thionyl chloride; hydrogenolysis of the latter compound provides 4,5‐dimethylimidazole in an overall 80–90% yield, doubling the yield obtained by the classical method.