反应详情

温度

23 °C

4-Amino-3-chloro-6-(4-cyclopropylphenyl)-5-fluoropicolinic acid. A 2 M solution of aqueous NaOH (600 μL, 1.2 mmol, 2.0 equiv) was added to a stirred suspension of methyl 4-amino-3-chloro-6-(4-cyclopropylphenyl)-5-fluoropicolinate (190 mg, 0.59 mmol, 1.0 equiv) in methyl alcohol (3.0 mL) at 23° C. The resulting heterogeneous white mixture was stirred at 23° C. for 3 h. The reaction mixture was adjusted to approximately pH=4 via dropwise addition of concentrated HCl and then concentrated via rotary evaporation. The residue was slurried in water and vacuum filtered to afford the desired product, 4-amino-3-chloro-6-(4-cyclopropylphenyl)-5-fluoropicolinic acid as a white powder (170 mg, 94% yield): mp 147-149° C.; IR (thin film) 3463 (s), 3339 (s), 3202 (m), 3084 (w), 3007 (w), 1721 (m), 1630 (s) cm−1; 1H NMR (300 MHz, DMSO-d6) δ 7.70 (m, 2H), 7.17 (m, 2H), 6.81 (br s, 2H), 1.96 (m, 1H), 0.99 (m, 2H), 0.71 (m, 2H); ESIMS m/z 307 ([M+H]+).

1. concentrationconcentrated via rotary evaporation
2. filtrationvacuum filtered