Trifluoroacetic acid → Ethyl 4-(4-fluoro-2-pyrrolidinyl)methoxy-3-methoxybenzoate

Participants

Reaction Steps

To a stirred solution of ethyl 4-[1-(tert-butoxycarbonyl)4-fluoro-2-pyrrolidinyl]methoxy-3-methoxybenzoate (482.2 mg, 1.213 mmol) in CH2Cl2 (10.0 mL) was added TFA (1.9 mL) at 0° C., and the mixture was stirred at room temp for 2 hr. The solvent was removed under a reduced pressure and the residue was made basic by the addition of 1 N NaOH and extracted with CHCl3. The extract was washed with brine, dried over Na2SO4, and concentrated under a reduced pressure to afford 348.7 mg (97%) ethyl 4-(4-fluoro-2-pyrrolidinyl)methoxy-3-methoxybenzoate as a brownish oil. 1H-NMR (400 MHz, CDCl3) δ 1.39 (t, J=6.8 Hz, 3H), 1.97 (ddt, J=1.5, 5.4, 14.7 Hz, 1H), 2.27 (dddd, J=5.9, 8.8, 14.7, 32.7 Hz, 1H), 3.02 (ddd, J=3.9, 13.1, 35.2 Hz, 1H), 3.36 (dd, J=12.7, 21.5 Hz, 1H), 3.65 (m, 1H), 3.90 (s, 3H), 4.09 (m, 1H), 4.35 (q, J=6.8 Hz, 2H), 5.17, 5.31 (br m each, 1H), 6.90 (d, J=8.3 Hz, 1H), 7.75 (d, J=2.0 Hz, 1H), 7.65 (dd, J=2.0, 8.3 Hz, 1H); MS (FAB) m/z 298 (M++1).

Provenance & Evidence