Sulfuric Acid → 3,6-Dichloro-4-(1-ethyl-1-hydroxymethylpropyl)pyridazine

Beteiligte Stoffe

Reaktionsschritte

Twenty g. of 3,6-dichloropyridazine, 2.3 g. of silver nitrate and 44.4 g. of 2,2-diethyl-1,3-propanediol were slurried in 280 ml. of water and 19.7 g. of sulfuric acid. To the mixture were added, simultaneously, solutions of 61.3 g. of ammonium persulfate in 200 ml. of water and 20 g. of silver nitrate in 40 ml. of water, over a period of 20 minutes at 55°. The mixture heated exothermically to 70°, and it was cooled to ambient temperature after the addition was complete. The aqueous layer was then decanted off, and the solids remaining were slurried twice in 800 ml. of diethyl ether. The resulting solution was shaken with the aqueous layer, and the layers were separated again. The aqueous layer was then made basic to pH 9 with ammonium hydroxide, and was re-extracted with 500 ml. of diethyl ether. The ether was evaporated under vacuum to obtain 46 g. of brown oil, which was purified by high performance liquid chromatography, eluting with 6:1 heptane:ethyl acetate. The product-containing fractions were combined and evaporated under vacuum to obtain, after recrystallization from diethyl ether/heptane, 0.54 g. of the desired product, m.p. 85°-87°.

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