[CH3:1]O[Na].[NH2:4][C:5]1[CH:6]=[C:7]([CH:10]=[CH:11][CH:12]=1)[C:8]#[N:9].[BH4-].[Na+].[OH-].[Na+]>CO>[CH3:1][NH:4][C:5]1[CH:6]=[C:7]([CH:10]=[CH:11][CH:12]=1)[C:8]#[N:9]To methanol (45 ml) is added CH3ONa (4.05 g, 75 mmol, 0.5 eq), and to this solution is dropwise added a solution of 3-aminobenzonitrile (17.70 g, 150 mmol, 1.0 eq) in methanol (60 ml). The mixture is stirred for 0.5 h. Then the reaction mixture is poured into a solution of polyformaldehyde (6.30 g, 210 mmol, 1.4 eq) in methanol (90 ml). After stirring at room temperature for 5.0 h, NaBH4 (content 96%) (6.00 g, 150 mmol, 1.0 eq) is added in portions. The mixture is stirred at room temperature for 10 min, and then is refluxed at elevated temperature for 10 min. The reaction mixture is cooled under ice-water bath, and added with 10% NaOH (aq) (90 ml) and stirred for 5 min. Methanol is removed under reduced pressure, and the left aqueous solution is extracted with ethyl acetate (150 ml*2). The organic phases are combined, washed with saturated brine twice, dried over anhydrous sodium sulfate, and concentrated to yield 21.89 g of brown oily crude product. The crude product is purified by neutral alumina column chromatography (eluent: petroleum ether/CH2Cl2=2/1) to give a light yellow oily pure product (17.34 g, yield: 87.6%).
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