Réaction #531886

Équation de réaction

Et3N

ethyl 3-(3-chloro-4-methyl-2-thienyl)-2-cyano-3-oxopropanoate

POCl3

→

ethyl 3-chloro-3-(3-chloro-4-methyl-2-thienyl)-2-cyanoacrylate

Rendement 66.9%

Solvants

CHCl3

Conditions de réaction

Traitement

1. 1
   Températurethe mixture was refluxed for 4 h
2. 2
   AutreThe mixture was evaporated
3. 3
   AutreAfter evaporation
4. 4
   workup.ADDITIONthe mixture was diluted with DCM (CH2Cl2) and with ice water
5. 5
   Extractionwas extracted with DCM (CH2Cl2)
6. 6
   Lavagewashed with brine
7. 7
   Séchagedried over MgSO4 before concentration under reduced pressure

Mode opératoire

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

Source