反应详情

4-Carboxybenzeneboronic acid (2.87 g, 17.3 mmol), 5-bromo-2-methoxypyridine (3.25 g, 17.3 mmol), 0.4M aqueous sodium carbonate (87 ml, 34.8 mmol) and acetonitrile (86 mL) were combined under nitrogen, and palladium tetrakistriphenylphosphine (1.00 g, 0.87 mmol) added. The reaction mixture was refluxed for 3 hours, cooled to room temperature, and filtered through celite (washed celite with 50:50 acetonitrile/water). Removed acetonitrile in vacuo, diluted residue with water (100 mL) and acidified to pH 2 with 2M HCl. The precipitate which formed was collected, washed with water, and dried under high vacuum to give the product as a white powder (3.6 g, 15.7 mmol). 1H NMR (DMSO) δ 12.90 (br s, 1H), 8.56 (s, 1H), 8.08 (dd, 1H), 7.98 (d, 2H), 7.75 (d, 2H), 6.94 (d, 1H), 3.90 (s, 3H). ESI MS (M+1)+: 230.

1. temperatureThe reaction mixture was refluxed for 3 hours
2. filtrationfiltered through celite (washed celite with 50:50 acetonitrile/water)
3. customThe precipitate which formed
4. customwas collected
5. washwashed with water
6. customdried under high vacuum