[CH3:1][C:2]1[O:6][N:5]=[C:4]([C:7]2[CH:8]=[C:9]([CH:14]=[CH:15][CH:16]=2)[C:10](OC)=[O:11])[N:3]=1.C1COCC1.[Li+].[BH4-].Cl>O>[CH3:1][C:2]1[O:6][N:5]=[C:4]([C:7]2[CH:8]=[C:9]([CH2:10][OH:11])[CH:14]=[CH:15][CH:16]=2)[N:3]=13.46 g of methyl 3-(5-methyl-1,2,4-oxadiazol-3-yl)benzoate (15.86 mmol) are dissolved in 50 ml of abs. THF in a 250 ml three-necked flask, and 0.691 g of LiBH4 (31.71 mmol) is subsequently introduced in portions with stirring at 0° C. under a nitrogen atmosphere, and the mixture is stirred without cooling for a further 20 h. For work-up, the reaction mixture is adjusted to pH 7 by slow dropwise addition of 1 N HCl with stirring, diluted with 100 ml of water and extracted 3× with 50 ml of dichloromethane. The combined organic phases are washed 1× 100 ml of water, dried over sodium sulfate and evaporated to dryness in a rotary evaporator. The purification is carried out by chromatography (50 g of silica gel/DCM+0-1% of MeOH). The product is crystallised from diethyl ether/petroleum ether; m.p. 57-58° C.
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