Hydrochloric Acid → 4-Amino-3-chloro-6-(4-chloro-2-fluoro-3-(1-fluoroethyl)phenyl)-5-fluoropicolinic acid

Participants

Reaction Conditions

Reaction Steps

4-Amino-3-chloro-6-(4-chloro-2-fluoro-3-(1-fluoroethyl)phenyl)-5-fluoropicolinic acid. A 2 molar (M) solution of aqueous sodium hydroxide (NaOH; 580 μL, 1.2 mmol, 4.0 equiv) was added to a stirred suspension of methyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-(1-fluoroethyl)phenyl)-5-fluoropicolinate (110 mg, 0.29 mmol, 1.0 equiv) in methyl alcohol (1.9 mL) at 23° C. The resulting homogeneous pale yellow solution was stirred at 23° C. for 20 h. The reaction mixture was adjusted to approximately pH=4 via dropwise addition of concentrated hydrochloric acid (HCl) and concentrated via rotary evaporation. The residue was slurried in water and vacuum filtered to afford the desired product, 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-(1-fluoroethyl)phenyl)-5-fluoropicolinic acid as a white powder (55 mg, 50%): IR (thin film) 3319 (m), 3193 (w), 2983 (w), 1719 (m), 1629 (s) cm−1; 1H NMR (300 MHz, DMSO-d6) δ 7.58 (t, J=9 Hz, 1H), 7.49 (d, J=9 Hz, 1H), 6.99 (br s, 2H), 6.15 (dq, J=44, 7 Hz, 1H), 1.71 (dd, J=23, 7 Hz, 3H); ESIMS m/z 365 ([M+H]+).

Provenance & Evidence