[F:1][CH:2]([F:24])[CH2:3][O:4][C@@H:5]1[CH2:9][N:8](C(OCC2C=CC=CC=2)=O)[C@H:7]([C:20]([O:22][CH3:23])=[O:21])[CH2:6]1>CO>[F:24][CH:2]([F:1])[CH2:3][O:4][C@@H:5]1[CH2:9][NH:8][C@H:7]([C:20]([O:22][CH3:23])=[O:21])[CH2:6]1To nitrogen flushed pressure bottle was added Pd/c (200 mg) under nitrogen. A solution of (2S,4S)-1-benzyl 2-methyl 4-(2,2-difluoroethoxy)pyrrolidine-1,2-dicarboxylate (2.0 g, 5.83 mmol) in MeOH (140 mL) was added to the bottle. The reaction mixture was hydrogenated at 50 psi overnight. The reaction mixture was passed through a pad of celite and washed with MeOH. The filtrate was concentrated and the residue was used for the next step without purification. 1H NMR (CDCl3, 400 MHz) δ ppm 3.56-3.79 (1H, m), 3.96 (1H, br s), 3.60-3.70 (1H, m), 3.62 (3H, s), 3.43-3.50 (2H, m), 3.07-3.09 (1H, m), 2.94-3.03 (1H, m), 2.78-2.87 (1H, m), 2.05-2.15 (2H, m); 13C NMR (126 MHz, CDCl3) δ ppm 174.72 (1C), 114.40 (1C, t, J=241 Hz), 80.41 (1C), 67.96 (1C, t, J=27.6 Hz), 58.78 (1C), 52.40 (1C), 52.29 (1C), 52.19 (1C, s), 35.96 (1C).
Wird geladen…