Cesium carbonate → 2-[(5-Chloro-2-{[3-methyl-1-(1-methylethyl)-1H-pyrazol-5-yl]amino}-4-pyridinyl)amino]-4-fluorobenzoic acid

Participants

Reaction Steps

To a degassed solution of 2,5-dichloro-4-iodopyridine (5 g, 18.26 mmol), 2-amino-4-fluorobenzonitrile (2.485 g, 18.26 mmol) and potassium triphosphate (11.63 g, 54.8 mmol) in 1,4-dioxane (60 ml) stirred under nitrogen at the room temperature was added DPEPhos (0.787 g, 1.460 mmol) and palladium acetate (0.164 g, 0.730 mmol). The reaction mixture was stirred at the reflux for 18 hr. The reaction mixture was filtered. 3-Methyl-1-(1-methylethyl)-1H-pyrazol-5-amine (2.54 g, 18.26 mmol) and cesium carbonate (17.84 g, 54.8 mmol) were added. The reaction mixture was degassed and palladium acetate (0.164 g, 0.730 mmol) and DPEPhos (0.787 g, 1.460 mmol) were added. The reaction mixture was refluxed overnight. The reaction mixture was filtered. NaOH (60 mL, 60.0 mmol) was added and the reaction mixture refluxed overnight. Ethyl acetate was added and the layers were separated. The combined organics were washed with 1 M NaOH (40 ml). The combined aqueous layers were washed with ethyl acetate, and neutralized with acetic acid. 2-[(5-Chloro-2-{[3-methyl-1-(1-methylethyl)-1H-pyrazol-5-yl]amino}-4-pyridinyl)amino]-4-fluorobenzoic acid (2.5 g, 6.19 mmol, 33.9% yield) was isolated by filtration as a yellow solid. 1H NMR (400 MHz, DMSO-d6) ppm 1.29 (d, J=6.57 Hz, 6 H) 2.12 (s, 3 H) 4.43 (quin, J=6.57 Hz, 1 H) 5.99 (s, 1 H) 6.86 (s, 1 H) 6.87-6.93 (m, 1 H) 7.34 (dd, J=11.62, 2.53 Hz, 1 H) 8.03-8.10 (m, 2 H) 8.62 (s, 1 H) 10.65 (br. s., 1 H); HPLC Rt=2.57 min, MS (ESI): 404.2 [M+H]+.

Provenance & Evidence