Water → HCID 12874107, Verbindung
Reaktionsgleichung
C(O)(C)C.O.[Cl:6][C:7]1[S:8][CH:9]=[C:10]([CH:13]=[O:14])[C:11]=1[Cl:12].[BH4-].[Na+]>ClCCl>[Cl:6][C:7]1[S:8][CH:9]=[C:10]([CH2:13][OH:14])[C:11]=1[Cl:12]Komponenten
6
C(O)(C)C.O.[Cl:6][C:7]1[S:8][CH:9]=[C:10]([CH:13]=[O:14])[C:11]=1[Cl:12].[BH4-].[Na+]>ClCCl>[Cl:6][C:7]1[S:8][CH:9]=[C:10]([CH2:13][OH:14])[C:11]=1[Cl:12]300 ml of isopropanol, 300 ml of water and 200 g of 2,3-dichlorothiophene-4-aldehyde are placed in a 2 liter flask; over a period of 45 minutes, 16 g of sodium borohydride is added in portions. The reaction is exothermic and is cooled to take place at from 35° to 40° C. Subsequently, the two-phase mixture is stirred for 30 minutes at this temperature and then 300 ml of water and 500 ml of dichloromethane are added. After the phases have been separated, the aqueous phase is extracted twice with 250 ml of dichloromethane. The organic phases are washed with 250 ml of water and concentrated. The oily residue is taken up in cyclohexane; there is obtained 182 g (87.3% of theory) of crystalline 2,3-dichloro-4-hydroxymethylthiophene, m.p.: 63° to 65° C.
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