反应详情

2-Bromo-1-(2-pyridyl)ethanol can be obtained by adding, over the course of one hour, an ice-cold solution of sodium borohydride (17.2 g.) in water (310 cc.) to a solution of 2-(2-bromoacetyl)pyridine hydrobromide (82.9 g.) in methanol (830 cc.) kept at -10° C. The mixture is allowed to return to a temperature of about 20° C. and the pH is brought to 2 by adding 48% hydrobromic acid (70 cc.). The mixture is concentrated to dryness under reduced pressure (30 mm.Hg) at a temperature below 40° C. The residue is taken up in distilled water (400 cc.) and the solution is decolourised by treatment with decolourising charcoal. The solution is brought to pH 7-8 by adding sodium bicarbonate (50 g.). The mixture is extracted with diethyl ether (1,500 cc.) and the extracts are dried over anhydrous potassium carbonate. After filtration and concentration under reduced pressure (30 mm.Hg), 2-bromo-1-(2-pyridyl)-ethanol (49 g.) is obtained in the form of an oil.

1. additionby adding, over the course of one hour
2. customkept at -10° C
3. customto return to a temperature of about 20° C.
4. concentrationThe mixture is concentrated to dryness under reduced pressure (30 mm.Hg) at a temperature below 40° C
5. additionby adding sodium bicarbonate (50 g.)
6. extractionThe mixture is extracted with diethyl ether (1,500 cc.)
7. dry with materialthe extracts are dried over anhydrous potassium carbonate
8. filtrationAfter filtration and concentration under reduced pressure (30 mm.Hg)