[NH:1]1[CH:5]=[CH:4][C:3]([CH2:6][CH2:7][CH2:8][OH:9])=[CH:2]1>[Pt](=O)=O.C(O)(=O)C>[NH:1]1[CH2:5][CH2:4][CH:3]([CH2:6][CH2:7][CH2:8][OH:9])[CH2:2]1A solution of 3-(1H-pyrrol-3-yl)-1-propanol (400 mg, 3.20 mmol) in 5 mL of freshly distilled glacial acetic acid containing 40 mg of platinum(IV) oxide was hydrogenated with a H2 balloon for 2 h at 35° C. The catalyst was removed by filtration, and the solvent was evaporated. The residue was heated under reflux for 0.5 h with 4 mL of 30% aqueous NaOH solution to saponify any acetate ester that may have formed. The mixture was extracted with CH2Cl2, and the organic phase was concentrated to obtain the crude pyrrolidine (0.35 g, 85%) as a light-yellow oil, which could be used without purification in the following step. 1H NMR (CDCl3, 300 MHz) δ 3.66 (t, 2H, J=6.3 Hz), 2.62 (dd, 1H, J=7.2, 10.5 Hz), 2.91-2.99 (m, 2H), 2.51 (dd, 1H, J=7.2, 10.8 Hz), 1.93-2.15 (m, 2H), 1.56-1.65 (m, 2H), 1.46 (t, 2H, J=7.2 Hz), 1.37-1.41 (m, 2H). LC-MS (ESI) m/z 130 (M+H+).
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