反应详情

温度

100 °C

In 100 ml of N,N-dimethylformamide was suspended 11 g of 50% sodium hydride which had been washed with n-hexane and the suspension was stirred under ice cooling. Thereafter, 37.6 g (0.2 mole) of diethyl ethylmalonate was added dropwise thereto and stirring was continued until evolution of hydrogen ceased. Subsequently, a solution of 31.51 g (0.2 mole) of p-chloronitrobenzene in 50 ml of N,N-dimethylformamide was added dropwise. At the end of the dropwise addition, the mixture was heated on an oil bath at 100° C. for 9 hours and N,N-dimethylformamide was distilled off in vacuo. The residue was extracted with ethyl acetate and the ethyl acetate layer was washed with 5% hydrochloric acid and saturated sodium chloride solution and then dried over magnesium sulfate. The ethyl acetate was distilled off in vacuo and the residue was subjected to chromatography on silica gel eluting with a mixture of benzene and n-hexane (1:1) to give 48.64 g (0.157 mole, 79% yield) of diethyl 2-ethyl-2-(4-nitrophenyl)malonate.

1. washhad been washed with n-hexane
2. stirringstirring
3. additionAt the end of the dropwise addition
4. distillationN,N-dimethylformamide was distilled off in vacuo
5. extractionThe residue was extracted with ethyl acetate
6. washthe ethyl acetate layer was washed with 5% hydrochloric acid and saturated sodium chloride solution
7. dry with materialdried over magnesium sulfate
8. distillationThe ethyl acetate was distilled off in vacuo
9. additionthe residue was subjected to chromatography on silica gel eluting with a mixture of benzene and n-hexane (1:1)