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Sodium borohydride (5 g) was added in two portions, over 40 minutes, to an ice-cooled solution of 2-(3,4-dichlorophenyl)-3-(1,3-dioxolan-2-yl)propan-1-al (53.5 g) (see Preparation 14) in ethanol (300 ml). The mixture was stirred for a further 30 minutes before removing the solvent under reduced pressure to give a residue. This was suspended in water (200 ml), cooled to 0° C. and the mixture acidified (pH<6) with glacial acetic acid. Dichloromethane was added and the aqueous phase basified (pH>8) by addition of solid sodium carbonate. A further amount of dichloromethane (200 ml) was added and the organic and aqueous phases separated. The aqueous phase was further extracted with dichloromethane (200 ml). The organic phases were combined, washed with brine, dried over anhydrous sodium sulphate and the solvent removed under reduced pressure to give 2-(3,4-dichlorophenyl)-3-(1,3-dioxolan-2-yl)propan-1-ol (54.6 g) as a yellow oil.

1. custombefore removing the solvent under reduced pressure
2. customto give a residue
3. customthe organic and aqueous phases separated
4. extractionThe aqueous phase was further extracted with dichloromethane (200 ml)
5. washwashed with brine
6. dry with materialdried over anhydrous sodium sulphate
7. customthe solvent removed under reduced pressure