[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.[BH4-].[Na+].CO>O1CCCC1>[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]=1In 200 ml of tetrahydrofuran is dissolved 26.8 g of ethyl 5-(1-benzyloxycarbonyl-4-piperidyl)valerate, and 13.4 g of sodium borohydride is added to the solution. Methanol (40 ml) is added dropwise to the mixture at 70° to 80° C. with stirring over the period of 1.5 hours, and after the addition is completed, refluxing is effected for another 2 hours. The reaction solution is concentrated under reduced pressure, and 300 ml of water is added to the residue, followed by extraction with 300 ml of ethyl acetate. The extract is washed with 50 ml of 1N hydrochloric acid and 50 ml of water successively, dried over anhydrous magnesium sulfate and concentrated under reduced pressure to give 23 g of 5-(1-benzyloxycarbonyl-4-piperidyl)pentanol as a colorless oily material.
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