反应详情

Sodium borohydride (2.03 g) was added portionwise to a solution of 2-(3,4-dichlorophenyl)-4-(tetrahydropyran-2-yloxy)butan-1-al (17.02 g) (see Preparation 27) in 2-propanol (250 ml). The mixture was stirred at room temperature overnight and glacial acetic acid (4 ml) carefully added, followed by addition of water (2 ml). The solvent was removed under reduced pressure to give a residue which was dissolved in dichloromethane and washed sequentially with water, dilute aqueous sodium hydrogen carbonate solution and brine. The solution was dried over anhydrous sodium sulphate and the solvent removed under reduced pressure. The crude product was chromatographed on silica gel eluting with 1:1, by volume, ethyl acetate:hexane to give 2-(3,4-dichlorophenyl)-4-(tetrahydropyran-2-yloxy)butan-1-ol (14.7 g) as a colourless oil and as a mixture of diastereomers.

1. customThe solvent was removed under reduced pressure
2. customto give a residue which
3. washwashed sequentially with water, dilute aqueous sodium hydrogen carbonate solution and brine
4. dry with materialThe solution was dried over anhydrous sodium sulphate
5. customthe solvent removed under reduced pressure
6. customThe crude product was chromatographed on silica gel eluting with 1:1, by volume, ethyl acetate