[CH3:1][O:2][C:3]1[C:8]([O:9][CH3:10])=[CH:7][CH:6]=[CH:5][C:4]=1[CH2:11][CH:12]([C:14]1[CH:19]=[CH:18][N:17]=[CH:16][CH:15]=1)[OH:13]>C(O)(=O)C.O=[Pt]=O>[CH3:1][O:2][C:3]1[C:8]([O:9][CH3:10])=[CH:7][CH:6]=[CH:5][C:4]=1[CH2:11][CH:12]([CH:14]1[CH2:19][CH2:18][NH:17][CH2:16][CH2:15]1)[OH:13]4-[2-(2,3-dimethoxyphenyl)-1-hydroxyethyl]pyridine (20.0 g, 0.077 mol) in acetic acid (170 ml) over 1.5 g of PtO2 was hydrogenated for 45 minutes on a Parr shaker. The reaction was filtered through Celite and filtrate combined with another run of 21.0 g (0.08 mol). The combined filtrates were concentrated in vacuo and the resulting oil was diluted with water. The aqueous solution was made basic with 50% aqueous NaOH, and the basic mixture extracted with EtOAc. The organic extract was washed with water, dried (magnesium sulfate) and then concentrated to afford 34.3 g of an oil that solidified upon standing. The solid was removed and recrystallized twice from isopropyl ether at 5° C. to afford the piperidine as a white solid, mp 82-84° C.
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