H. J. Hertog, D. Buurman
Sep 2, 2010
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0
Influential Citations
8
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Journal
Recueil des Travaux Chimiques des Pays-Bas
Abstract
Syntheses of 2-hydroxy-4-methoxypyridine, 4-hydroxy-2-methoxypyridine, 4-methoxy-N-methylpyridone-2, and 2-methoxy-N-methylpyridone-4 are described. The ultraviolet absorption spectra of 50% aqueous ethanolic solutions of the above-mentioned compounds and of 2,4-dihydroxypyridine and 2,4-di-methoxypyridine are measured. Comparison of these spectra enables the determination of the predominant tautomeric structures of 2,4-dihydroxypyridine and its derivatives. It appears that the chief structure of 2,4-dihydroxypyridine in aqueous ethanol is that of 4-hydroxypyridone-2. Finally it is shown that the methyl derivative of 2,4-dihydroxypyridine, obtained by Maquenne and Philippe1 ) when heating ricinine with hydrochloric acid solution or by conversion of 4-methoxy-N-methylpyridone-2 with the same reagent according to Spath and Tschelnitz2 ), is 4-hydroxy-N-methylpyridone-2.