[C:1]([N:5]1[CH2:9][C@@H:8]([C:10]2[CH:15]=[CH:14][C:13]([F:16])=[CH:12][C:11]=2[F:17])[C@H:7]([C:18]([N:20]2[CH2:25][CH:24]=[C:23]([C:26]3[CH:31]=[CH:30][C:29]([Cl:32])=[CH:28][C:27]=3[CH2:33][C:34]([O:36][CH3:37])=[O:35])[CH2:22][CH2:21]2)=[O:19])[CH2:6]1)([CH3:4])([CH3:3])[CH3:2]>C(O)C.[Pt](=O)=O>[C:1]([N:5]1[CH2:9][C@@H:8]([C:10]2[CH:15]=[CH:14][C:13]([F:16])=[CH:12][C:11]=2[F:17])[C@H:7]([C:18]([N:20]2[CH2:25][CH2:24][CH:23]([C:26]3[CH:31]=[CH:30][C:29]([Cl:32])=[CH:28][C:27]=3[CH2:33][C:34]([O:36][CH3:37])=[O:35])[CH2:22][CH2:21]2)=[O:19])[CH2:6]1)([CH3:4])([CH3:3])[CH3:2]A mixture of methyl [2-(1-{[(3S,4R)-1-tert-butyl-4-(2,4-difluorophenyl)pyrrolidin-3-yl]carbonyl}-1,2,3,6-tetrahydropyridin-4-yl)-5-chlorophenyl]acetate (1-8) (2.60 mmol) and platinum (IV) oxide (0.300 g) in ethanol/glacial acetic acid (1:1, 20 mL) was hydrogenated at atmospheric pressure for approximately 15 h. The resulting mixture was filtered through a short column of celite®, eluting copiously with ethanol. The filtrate was evaporated and the residue was partitioned between methylene chloride and saturated aqueous sodium bicarbonate. The organic layer was separated and the aqueous phase was re-extracted twice with methylene chloride. The combined organic extracts were washed with water, brine, dried (Na2SO4), and concentrated in vacuo. Purification of the crude residue by flash chromatography on silica gel (gradient elution; 0%-15% methanol (containing 10% v/v ammonium hydroxide)/methylene chloride as eluent) furnished 1-9 (1.25 g) as a colorless foam (m/z (ES) 533 (MH+).
Loading…