Formaldehyde → 1-Benzyl-4-hydroxymethyl-2-methylimidazole

Participants

Reaction Steps

A mixture of 8.5 g (0.05 mole) of 1-benzyl-2-methylimidazole monohydrate, 50 ml of 36% formaldehyde, 6 ml of acetic acid and 8.0 g (0.098 mole) of sodium acetate is stirred and heated at reflux for 26 hours. It was then stirred over a weekend (about 65 hours) at room temperature and neutralized with solid sodium carbonate. The neutral solution was extracted with ethyl acetate, the extract dried (MgSO4) and evaporated under reduced pressure to an oil. Water (10 ml) and isopropanol (50 ml) were added to the oil, the solution stirred overnight then evaporated under reduced pressure. The oily residue obtained was taken up in water and the solution made strongly basic by addition of solid sodium hydroxide. It was chilled, layered with diethyl ether, and the white solid which formed removed by filtration and air dried. Yield=1.8 g (18%); m.p. 140°-146° C. It was purified by dissolution in 30 ml of hot (50° C.) ethyl acetate and filtration. Concentration of the filtrate to about two-thirds volume, and chilling, afforded 1.3 g of white solid; m.p. 147°-151° C. Thin layer chromatography in the system ethyl acetate:methanol:diethylamine (80:10:10) gave a single spot.

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