N-bromobutanimide → 6-(4-bromo-5-methoxy-1H-pyrazol-1-yl)-N-(3-methoxypropyl)nicotinamide

Participants

Reaction Steps

Combined 5-methoxy-1-(5-((3-methoxypropyl)carbamoyl)pyridin-2-yl)-1H-pyrazole-4-carboxylic acid (2.19 g, 6.55 mmol), NBS (1.749 g, 9.83 mmol), and sodium bicarbonate (1.651 g, 19.65 mmol) in DMF (20 mL) and stirred at 20° C. for 1 h. The reaction was diluted with water (100 mL) and extracted with EtOAc (100 mL, then 2×50 mL). The combined organics were washed with brine, dried over magnesium sulfate and concentrated in vacuo to give a residue which was purified on a 120 g silica gel column eluted with 10 to 100% EtOAc in hexanes to give the title compound (2.348 g, 97% yield) as a white solid. MS m/z 369, 371 [M+H]+. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.78 (quin, J=6.6 Hz, 2H) 3.25 (s, 3H) 3.30-3.37 (m, 2H) 3.40 (t, J=6.3 Hz, 2H) 4.05 (s, 3H) 7.79 (dd, J=8.6, 0.5 Hz, 1H) 7.85 (s, 1H) 8.38 (dd, J=8.6, 2.3 Hz, 1H) 8.74 (t, J=5.6 Hz, 1H) 8.96 (dd, J=2.4, 0.6 Hz, 1H).

Provenance & Evidence