反应详情

温度

5 °C

To a solution of ethyl 3-(3-chloro-4-methyl-2-thienyl)-2-cyano-3-oxopropanoate (15.40 g, 56.67 mmol, 1 eq.) in 200 ml of CHCl3 was added POCl3 (86.9 g, 566 mmol, 10 eq.). Et3N (14.33 g, 141.6 mmol, 2.5 eq.) was added dropwise with stirring at 5° C., and the mixture was refluxed for 4 h. The mixture was evaporated. After evaporation, the mixture was diluted with DCM (CH2Cl2) and with ice water and was extracted with DCM (CH2Cl2) and washed with brine. The organic layers were combined and dried over MgSO4 before concentration under reduced pressure. The residue was subjected to column chromatography on silica gel to give ethyl 3-chloro-3-(3-chloro-4-methyl-2-thienyl)-2-cyanoacrylate (11 g, 66% yield) as a mixture of 2 isomers

1. temperaturethe mixture was refluxed for 4 h
2. customThe mixture was evaporated
3. customAfter evaporation
4. additionthe mixture was diluted with DCM (CH2Cl2) and with ice water
5. extractionwas extracted with DCM (CH2Cl2)
6. washwashed with brine
7. dry with materialdried over MgSO4 before concentration under reduced pressure