Reaktion #66579

Reaktionsgleichung

3-acetyl-4-hydroxy-2H-1-benzopyran-2-one

3-chloro-4-(trifluoromethoxy)benzaldehyde

piperidine

→

4-hydroxy-3-[3-[3-chloro-4-(trifluoromethoxy)phenyl]-1-oxo-2-propenyl]-2H-1-benzopyran-2-one

Ausbeute 36.2%

Lösungsmittel

chloroform

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturwas heated
2. 2
   Temperaturunder refluxing for 2 hours and 30 minutes
3. 3
   Einengenthe reaction mixture was concentrated under reduced pressure
4. 4
   SonstigeResulting crystals
5. 5
   Waschenwere washed with 40 ml of t-butyl methyl ether

Vorschrift

A mixture of 2.25 g of 3-acetyl-4-hydroxy-2H-1-benzopyran-2-one, 2.25 g of 3-chloro-4-(trifluoromethoxy)benzaldehyde, 20 ml of chloroform and 0.7 ml of piperidine was heated under refluxing for 2 hours and 30 minutes. After cooled to room temperature, the reaction mixture was concentrated under reduced pressure, and the residue was subjected to column chromatography. Resulting crystals were washed with 40 ml of t-butyl methyl ether to obtain 1.49 g of 4-hydroxy-3-[3-[3-chloro-4-(trifluoromethoxy)phenyl]-1-oxo-2-propenyl]-2H-1-benzopyran-2-one [Compound No. (1c-6)] was obtained as a yellow crystal.

Quelle