[F:1][C:2]1[CH:3]=[C:4]([CH:7]=[C:8]([F:12])[C:9]=1[S:10][CH3:11])[CH:5]=[O:6].[BH4-].[Na+].Cl.O>C1COCC1>[F:12][C:8]1[CH:7]=[C:4]([CH2:5][OH:6])[CH:3]=[C:2]([F:1])[C:9]=1[S:10][CH3:11]
To a solution of 3,5-difluoro-4-(methylthio)-benzaldehyde (31.3 g, 0.166 mol) in anhydrous THF (200 mL) cooled with a cold water bath was added sodium borohydride (1.6 g, 0.042 mol) in portions over 30 minutes. After stirring 1 hour at room temperature, excess dilute HCl was added, until gas evolution ceased. Water (600 mL) was added and the mixture extracted with dichloromethane (1×500 mL, 1×100 mL). The combined extracts were washed once with water, dried with magnesium sulfate, and concentrated. Purification by silica gel chromatography using 3% ethyl acetate/10% dichloromethane in hexanes initially, and eluting product with 60% ethyl acetate in hexanes gave [3,5-difluoro-4-(methylthio)-phenyl]methanol as a light yellow liquid (24.8 g, 78%). 1H NMR (CDCl3/400 MHz) 6.88-6.93 (m, 2H), 4.65 (s, 2H), 2.42 (s, 3H). HRMS m/z 190.0266 (M+H+, calcd 190.0264).
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