Reaction Steps
To a stirred solution of methyl 4-[(2S, 4S)-1-tert-butoxycarbonyl-4-(2-naphthyloxy)-2-pyrrolidinyl]methoxybenzoate (870 mg, 1.74 mmol) in CH2Cl2 (24 ml) was added TFA (6 ml) at room temperature. The mixture was stirred over night, which was concentrated in vacuo. The residue was diluted with CH2Cl2 and made basic by the addition of 1 N NaOH, which was extracted with CH2Cl2. The organic layer was washed with brine, dried over NaSO4 and concentrated. The residue was chromatographed on silica gel [100 g, n-hexane/EtOAc(211)], to give methyl 4-[(2S, 4S)-4-(2-naphthyloxy)-2-pyrrolidinyl]methoxybenzoate (750 mg, 100%) as a black oil 1H-NMR (CDCl3) δ 1.99 (dd, J=14.2, 5.6 Hz, 1H), 2.48 (m, 1H), 3.22 (dd, J=12.2, 4.6 Hz, 1H), 3.43 (d, J=12.5 Hz, 1H), 3.67 (m, 1H), 3.86 and 3.87 (s, 3H, amide isomers), 4.11 (m, 2H), 5.04 (m, 1H), 6.83 (d, J=8.5 Hz, 1H), 6.89 (d, J=8.8 Hz, 2H), 7.07 (d, J=2.0 Hz, 1H), 7.12 (d, J=9.0 Hz, 1H), 7.33 (dt, J=8.1, 1.2 Hz, 1H), 7.44 (dt, J=6.8, 1.2 Hz, 1H), 7.70 (d, J=8.1 Hz, 1H), 7.75 (dd, J=9.0, 5.1 Hz, 2H), 7.90 (d, J=8.5 Hz, 1H), 7.96 (dd, J=6.8, 2.0 Hz, 2).
