反应详情

A mixture of 3-bromo-5-chloropyrazin-2-amine (624 mg, 2.99 mmol, Ark Phar. Inc), 6-methoxypyridin-3-ylboronic acid (1374 mg, 8.98 mmol, Combi. Blocks), copper (II) acetate (896 mg, 4.49 mmol, Aldrich, St. Louis, Mo.), and N,N-diisopropylethylamine (2.083 mL, 11.97 mmol, Aldrich, St. Louis, Mo.) in dichloromethane (20 mL) was stirred at room temperature for 48 h. The mixture was filtered through a pad of Celite® (diatomaceous earth) and washed with EtOAc. The solvent was removed in vacuo and the residue was purified by silica gel chromatography eluting with 10% EtOAc/hexanes to give 3-bromo-5-chloro-N-(6-methoxypyridin-3-yl)pyrazin-2-amine (165 mg, 0.523 mmol, 17.47% yield). 1H NMR (300 MHz, CDCl3) δ 3.95 (s, 3H) 6.79 (d, J=8.77 Hz, 1H) 6.92 (s, 1H) 7.77 (dd, J=8.84, 2.41 Hz, 1H) 8.01 (s, 1H) 8.29 (d, J=2.05 Hz, 1H). m/z (ESI, +ve ion) 316.9 (M+H)+.

1. filtrationThe mixture was filtered through a pad of Celite® (diatomaceous earth)
2. washwashed with EtOAc
3. customThe solvent was removed in vacuo
4. customthe residue was purified by silica gel chromatography
5. washeluting with 10% EtOAc/hexanes