反应详情

温度

85 °C

A mixture of 3-(2-chloroethoxy)-1-(3,4-dichlorophenyl)-5-methyl-1H-pyrazole (0.2 g, 0.65 mmol), ethyl piperazine-1-carboxylate (0.113 g, 0.72 mmol), K2CO3 (270 mg, 1.96 mmol) and NaI (98 mg, 0.65 mmol) in dry dimethylformamide (6 ml) was warmed overnight at 85° C., and then an additionally 16 hrs at 95° C., in a dry nitrogen atmosphere. Solvents were evaporated in vacuo and the crude residue partitioned in water/ethyle acetate. The combined organic extracts were washed with water, dried on Na2SO4 and concentrated in vacuo to obtain a crude oil, which was purified by column chromatography on silica gel (ethyl acetate/petroleum ether 8:2) yielding 69 mg of ethyl 4-{2-[1-(3,4-dichlorophenyl)-5-methyl-1H-pyrazol-3-yloxy]ethyl}piperazine carboxylate as a colourless oil

1. customan additionally 16 hrs
2. customat 95° C.
3. customSolvents were evaporated in vacuo
4. customthe crude residue partitioned in water/ethyle acetate
5. washThe combined organic extracts were washed with water
6. customdried on Na2SO4
7. concentrationconcentrated in vacuo
8. customto obtain a crude oil, which
9. customwas purified by column chromatography on silica gel (ethyl acetate/petroleum ether 8:2)