反应详情

A mixture of 3-bromo-5-chloropyrazin-2-amine (780 mg, 3.74 mmol, Ark Phar. Inc., Libertyville, Ill.), 5-fluoro-6-methoxypyridin-3-ylboronic acid (1919 mg, 11.23 mmol, Anichem), N,N-diisopropylethylamine (1.953 mL, 11.23 mmol, Aldrich, St. Louis, Mo.) and copper (II) acetate (1.12 g, 5.61 mmol, Aldrich, St. Louis, Mo.) in dichloromethane (30 mL) was stirred at room temperature for 72 h. The reaction mixture was diluted with water (20 mL) and extracted with EtOAc (2×40 mL). The combined organic extracts were washed with saturated NaCl (20 mL) and dried over Na2SO4. The solution was filtered and concentrated in vacuo to give the crude material as a light-yellow solid. The crude product was purified by silica gel chromatography, eluting with 20% EtOAc/hexanes to give 3-bromo-5-chloro-N-(5-fluoro-6-methoxypyridin-3-yl)pyrazin-2-amine (218 mg, 0.654 mmol, 17.47% yield). 1H NMR (300 MHz, CDCl3) δ 4.03 (s, 3H) 7.00 (s, 1H) 7.82 (dd, J=11.25, 1.75 Hz, 1H) 8.04 (d, J=9.06 Hz, 2H). m/z (ESI, +ve ion) 331.9 (M+H)+.

1. extractionextracted with EtOAc (2×40 mL)
2. washThe combined organic extracts were washed with saturated NaCl (20 mL)
3. dry with materialdried over Na2SO4
4. filtrationThe solution was filtered
5. concentrationconcentrated in vacuo
6. customto give the crude material as a light-yellow solid
7. customThe crude product was purified by silica gel chromatography
8. washeluting with 20% EtOAc/hexanes