Sodium Hydroxide → [5-Fluoro-2-(3-nitro-benzylthiocarbamoyl)-phenoxy]-acetic acid

Participants

Reaction Steps

A suspension of [5-Fluoro-2-(3-nitro-benzylthiocarbamoyl)-phenoxy]-acetic acid ethyl ester (4.39 g, 11.2 mmol) in ethanol (40 mL) was treated with aq 2 N NaOH (11 mL, 22.4 mmol). After stirring for 4 h, the solution was concentrated in vacuo until most of the ethanol was removed, and the mixture was acidified to pH of 1 with 2 N HCl. After extracting with ethyl acetate, the organic layer was washed with saturated aq NaCl, dried over MgSO4 and concentrated to give [5-fluoro-2-(3-nitro-benzylthiocarbamoyl)-phenoxy]-acetic acid (4.0 g, 98%) as an off-white solid: mp 147–150° C.; Rf 0.27 (20% methanol in dichloromethane); 1H NMR (DMSO-d6 300 MHz) δ 13.23 (s, 1 H), 10.79 (t, J=5.7 Hz, 1 H), 8.23 (t, J=1.8 Hz, 1 H), 8.11 (ddd, J1=8.3 Hz, J2=2.7 Hz, J3=1.2 Hz, 1 H), 7.85 (br d, J=7.5 Hz, 1 H), 7.73 (dd, J, =8.9 Hz, J2=7.1 Hz, 1 H), 7.63 (t, J=8.1 Hz, 1 H), 7.03 (dd, J1=11.4 Hz, J2=2.4 Hz, 1 H), 6.86 (dt, J1=8.4 Hz, J2=2.4 Hz, 1 H), 5.07 (d, J=5.7 Hz, 2 H), 4.83 (s, 2 H). ESI-LC/MS m/z calcd for CO6 H13FN2O5S: 364.4. Found 363.0 (M−1)−. Anal. calcd for C16H13FN2O5S: C, 52.74: H, 3.60; N, 7.69. Found C, 52.65; H, 3.62; N, 7.58.

Provenance & Evidence