反应详情

温度

140 °C

To a solution of 1-methyl-1H-imidazole-4-carboxylic acid (1.5 g, 11.9 mmol) in DMF (30 mL), N-hydroxy-4-(trifluoromethoxy)benzimidamide (3.1 g, 14.3 mmol), HOBT (2.2 g, 14.3 mmol) and EDCI (2.7 g, 14.3 mmol) were added in sequence. The mixture was stirred at 140° C. overnight, then cooled to RT, quenched by water (100 mL), and extracted with EtOAc (2×50 mL). The combined organic phases were washed by water (3×50 mL) and brine (50 mL), dried over Na2SO4, filtered, and concentrated to afford the crude product, which was purified by silica gel column chromatography (EtOAc:Petroleum ether=1:5) to give 5-(1-methyl-1H-imidazol-4-yl)-3-(4-(trifluoromethoxy)phenyl)-1,2,4-oxadiazole as a white solid (1.8 g, 40.0%). MS (ES+) C13H9F3N4O2 requires: 310, found: 311 [M+H]+.

1. temperaturecooled to RT
2. customquenched by water (100 mL)
3. extractionextracted with EtOAc (2×50 mL)
4. washThe combined organic phases were washed by water (3×50 mL) and brine (50 mL)
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated
8. customto afford the crude product, which
9. customwas purified by silica gel column chromatography (EtOAc:Petroleum ether=1:5)