反应详情

In 80 ml of dichloromethane was suspended 5.0 g of phenylmalonic acid. To the suspension was added 4.25 g of 2,2,2-trichloroethanol. To the mixture was added little by little 5.8 g of dicyclohexylcarbodiimide under ice-cooling while stirring. The stirring was continued at the same temperature for 20 minutes, then at room temperature for further 3 hours. The precipitates formed were then filtered off, and the precipitates were washed with a small volume of dichloromethane. The filtrate was washed with water and extracted with an aqueous solution of sodium hydrogen-carbonate. The aqueous layer was acidified with 1N HCl, then extracted with ethyl acetate. The extract was washed with saline, dried over MgSO4 and the solvent was distilled off. To the residue was added chloroform and some precipitated phenyl malonic acid was removed by filtration. The filtrate was concentrated to give 3.2 g of crude phenyl malonic acid mono(2,2,2-trichloroethyl)ester.

1. temperaturecooling
2. waitat room temperature for further 3 hours
3. customThe precipitates formed
4. filtrationwere then filtered off
5. washthe precipitates were washed with a small volume of dichloromethane
6. washThe filtrate was washed with water
7. extractionextracted with an aqueous solution of sodium hydrogen-carbonate
8. extractionextracted with ethyl acetate
9. washThe extract was washed with saline
10. dry with materialdried over MgSO4
11. distillationthe solvent was distilled off
12. additionTo the residue was added chloroform
13. customsome precipitated phenyl malonic acid was removed by filtration
14. concentrationThe filtrate was concentrated