反应详情

温度

0 °C

Alternative procedure: Potassium tert-butoxide (28.1 g, 0.25 mol) was added, in 2 portions, to a stirred solution of 3-amino-5-fluoropyridine (14.0 g, 0.125 mol) in anhydrous THF (400 mL) under a nitrogen atmosphere at 0° C. After 45 min stirring at 0° C., the resulting dark purple solution was transferred by cannula to a stirred solution of 2,4-difluoro-1-nitrobenzene (13.8 mL, 0.125 mol) in anhydrous THF (100 mL), at 0° C., over a period of 20 min. The resulting mixture was stirred for a further 45 min then poured onto a RT solution of NH4Cl (1:1 saturated solution:H2O, 1 L). The resulting yellow precipitate was filtered, washed with water and dried under vacuum at 50° C. to afford the title compound as an orange solid (18.2 g). The filtrate was partially evaporated, to remove some of the reaction solvent, the resulting precipitate was filtered then triturated with EtOAc to give a further 3.5 g of the title compound (overall 21.7 g, 69%) LCMS (Method C): RT 3.18 min [M+H]+ 252.13

1. stirringThe resulting mixture was stirred for a further 45 min
2. filtrationThe resulting yellow precipitate was filtered
3. washwashed with water
4. customdried under vacuum at 50° C.