[CH2:1]([O:8][C:9]([N:11]1[CH2:16][CH2:15][CH:14]([CH2:17][CH2:18][CH2:19][CH2:20][C:21](OCC)=[O:22])[CH2:13][CH2:12]1)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.O1CCCC1.[BH4-].[Na+]>CO>[CH2:1]([O:8][C:9]([N:11]1[CH2:16][CH2:15][CH:14]([CH2:17][CH2:18][CH2:19][CH2:20][CH2:21][OH:22])[CH2:13][CH2:12]1)=[O:10])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1To a stirred mixture of ethyl 5-(1-benzyloxycarbonyl-4-piperidyl)valerate (26.8 g), tetrahydrofuran (200 ml) and sodium borohydride (13.4 g) is added dropwise methanol (40 ml) for 1.5 hours at 70°-80° C. After the addition is complete, the mixture is refluxed for 2 hours with stirring. After evaporation of solvent, the residue is diluted with water (300 ml) and extracted with ethyl acetate (300 ml). The extract is washed successively with 1N hydrochloric acid and water, dried over anhydrous magnesium sulfate and evaporated in vacuo to give 5-(1-benzyloxycarbonyl-4-piperidyl)pentanol (23 g) as a colorless oil.
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