[H-].[Al+3].[Li+].[H-].[H-].[H-].[CH2:7]([N:14]1[CH2:19][CH2:18][C@@H:17]([CH3:20])[CH2:16][C@@H:15]1[C:21]([NH2:23])=O)[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1.O.[OH-].[Na+]>O1CCCC1>[NH3:14].[CH2:7]([N:14]1[CH2:19][CH2:18][C@@H:17]([CH3:20])[CH2:16][C@@H:15]1[CH2:21][NH2:23])[C:8]1[CH:13]=[CH:12][CH:11]=[CH:10][CH:9]=1Lithium aluminum hydride (9.2 ml, 1M in tetrahydrofuran, 9.2 mmol) was added to a solution of (2R,4R)-1-benzyl-4-methyl-2-piperidinecarboxamide (preparation 86) (3.5 g, 15.0 mmol) in tetrahydrofuran (60 ml), and the reaction heated under reflux overnight. The reaction was cooled in an ice-bath, water (0.4 ml), 15% NaOH solution (0.4 ml), and water (1.2 ml) were added consecutively, and the resulting precipitate filtered off. The filtrate was concentrated under reduced pressure, re-dissolved in dichloromethane and washed with brine, dried over Na2SO4 and evaporated under reduced pressure. The crude product was purified by column chromatography on silica gel using an elution gradient of dichloromethane:methanol:0.88 ammonia (100:0:0 to 85:15:1) to give the title compound as a yellow oil, (650 mg, 20%).
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