反应详情

温度

80 °C

To a mixture of 2,4-dichloro-1-(2-methoxy-ethoxymethyl)-1H-benzoimidazole (0.660 g, 2.40 mmol) and DMF (10 mL), was added Cs2CO3 (1.88 g, 5.76 mmol) and 1H-pyrazole-4-carboxylic acid ethyl ester (0.400 g, 2.88 mmol). The resulting mixture was then heated to 80° C. for 2 h. The mixture was cooled to 23° C., poured into brine (40 mL), and extracted with EtOAc (3×40 mL). The combined organic layers were washed with brine (40 mL), dried, filtered, and concentrated under reduced pressure. The residue was purified (FCC) (10-50% EtOAc/hexanes) to yield the titled compound as a mixture of regioisomers (0.880 g, 97%). MS (ESI/CI): mass calcd. for C17H19ClN4O4, 378.1; m/z found, 379.1 [M+H]+. 1H NMR (500 MHz, CDCl3): 8.97 (s, 1H), 8.80 (s, 1H), 8.22 (s, 1H), 8.20 (s, 1H), 7.65 (s, 1H), 7.53 (s, 1H), 7.40-7.23 (m, 4H), 6.38 (s, 2H), 6.16 (s, 2H), 4.41-4.31 (m, 4H), 3.68-3.59 (m, 2H), 3.57-3.49 (m, 2H), 3.48-3.41 (m, 2H), 3.41-3.35 (m, 2H), 3.31 (s, 3H), 3.25 (s, 3H), 1.38 (td, J=7.1, 1.2 Hz, 6H).

1. temperatureThe mixture was cooled to 23° C.
2. extractionextracted with EtOAc (3×40 mL)
3. washThe combined organic layers were washed with brine (40 mL)
4. customdried
5. filtrationfiltered
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified (FCC) (10-50% EtOAc/hexanes)