反应详情

528 mg (13.1 mmole) of sodium borohydride are added to a solution, cooled to 0°, of 3.3 g (13.1 mmole) of 5-chloro-6-(piperidin-1-yl)-benzofuran-3(2H)-one, according to Example 2, in 80 ml of methanol. The whole is subsequently stirred for a further 4 hours at 0°. The reaction mixture is diluted with water, adjusted to pH 6-7 with dilute ammonium chloride solution and extracted several times with methylene chloride. The organic phases are washed with water, combined, dried over sodium sulphate and concentrated in a vacuum rotary evaporator. Chromatography over silica gel using methylene chloride as eluant (Rf =0.12) yields 5-chloro-3-hydroxy-6-(piperidin-1-yl)-2,3-dihydrobenzofuran in the form of an oil.

1. extractionextracted several times with methylene chloride
2. washThe organic phases are washed with water
3. dry with materialdried over sodium sulphate
4. concentrationconcentrated in a vacuum rotary evaporator