[H-].[Al+3].[Li+].[H-].[H-].[H-].C([O:14][C:15](=O)[C:16]1([CH2:29][C:30]2[CH:35]=[CH:34][CH:33]=[CH:32][C:31]=2[CH3:36])[CH2:21][CH2:20][N:19]([C:22]([O:24][C:25]([CH3:28])([CH3:27])[CH3:26])=[O:23])[CH2:18][CH2:17]1)C1C=CC=CC=1>CCOCC>[C:25]([O:24][C:22]([N:19]1[CH2:18][CH2:17][C:16]([CH2:15][OH:14])([CH2:29][C:30]2[CH:35]=[CH:34][CH:33]=[CH:32][C:31]=2[CH3:36])[CH2:21][CH2:20]1)=[O:23])([CH3:27])([CH3:28])[CH3:26]To a suspension of lithium aluminum hydride (0.32 g, 8.4 mmol) in anhydrous ether (50 ml) was added a solution of 4-(2-methylbenzyl)-N-t-butoxycarbonyl isonipecotic acid benzyl ester (3.0 g, 7.1 mmol) in anhydrous ether (25 ml) over 15 min. The resulting mixture was heated at gentle reflux for 1 hr. The reaction mixture was then quenched with the slow and successive addition of H2O (0.32 ml), 15% aqueous NaOH (0.96 ml), and H2O (0.96 ml). After stirring for 30 min, the mixture was filtered through celite and the filtrate washed with brine, dried (MgSO4), and concentrated in vacuo to a colorless syrup. Purification by chromatography (SiO2, gradient elution, 25 to 50% EtOAc in hexanes), afforded the product as a colorless gum. This material was recrystallized from EtOAc and hexane to afford a white solid. m.p. 104-106° C.
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