Potassium Fluoride → Methyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)-5-fluoropicolinate

Participants

Reaction Conditions

Reaction Steps

A stream of nitrogen was passed through a colorless mixture of methyl 4-amino-6-bromo-3-chloro-5-fluoropicolinate (2.8 g, 10 mmol) and 2-(4-chloro-2-fluoro-3-methoxyphenyl)-1,3,2-dioxaborinane (3.2 g, 13 mmol) in acetonitrile (CH3CN; 40 mL) and KF (1.7 g, 30 mmol) in H2O (20 mL) while heating to 50° C. (20-30 min). Dichloro-bis(triphenylphosphine)palladium(II) (PdCl2(PPh3)2; 140 mg, 0.2 mmol) was added, and the mixture was heated to 65° C. The reaction was monitored by HPLC and was complete after 5 h. The reaction mixture was filtered hot through a short pad of Celite then was diluted with H2O (20 mL) and allowed to cool. The product was collected by filtration. The light tan solid was dried under vacuum to give methyl 4-amino-3-chloro-6-(4-chloro-2-fluoro-3-methoxyphenyl)-5-fluoropicolinate (2.6 g, 72%): mp 169-170.5° C.; 1H NMR (400 MHz, DMSO-d6) δ 7.48 (d, J=8.4 Hz, 1H), 7.32 (t, J=7.7 Hz, 1H), 7.15 (s, 2H), 3.96 (s, 3H), 3.90 (s, 3H); 13C{1H} NMR (101 MHz, DMSO-d6) δ 164.85 (s), 153.11 (d, J=252.5 Hz), 146.29 (s), 144.52 (d, J=4.3 Hz), 143.74 (s), 142.75 (dd, J=227.1, 14.0 Hz), 136.38 (d, J=13.4 Hz), 128.58 (d, J=3.2 Hz), 125.87 (s), 125.54 (d, J=3.5 Hz), 122.89 (dd, J=13.8, 4.0 Hz), 113.01 (d, J=3.0 Hz), 61.61 (d, J=4.2 Hz), 52.70 (s); ESIMS m/z 364 ([M+H]+). Anal. Calcd for C14H10Cl2F2N2O3: C, 46.30; H, 2.78; N, 7.71. Found: C, 46.60; H, 2.68; N, 7.51.

Provenance & Evidence