Reaktion #4847

Reaktionsgleichung

2-methoxy-4-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]benzaldehyde

malonic acid

piperidine

→

3-{2 -methoxy-4-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]phenyl}-2-propenoic acid

Ausbeute 61.0%

Lösungsmittel

pyridine

Reaktionsbedingungen

Aufarbeitung

1. 1
   Temperaturgradually heated to 80°
2. 2
   TemperaturHeating
3. 3
   workup.STIRRINGstirring
4. 4
   TemperaturThe solution is then heated
5. 5
   Temperaturat reflux for an additional 3 hours
6. 6
   Temperaturcooled
7. 7
   Sonstigeevaporated at reduced pressure
8. 8
   Sonstigeto obtain a residual oil which
9. 9
   Extraktionis extracted into ether
10. 10
    WaschenThe resulting ether solution is washed with water and 1N hydrochloric acid
11. 11
    Trocknendried with anhydrous magnesium sulfate
12. 12
    Filtrationfiltered
13. 13
    Sonstigeevaporated at reduced pressure
14. 14
    Sonstigeto obtain a residual solid which
15. 15
    Sonstigeis recrystallized from chlorobutane/hexane mixed solvent

Vorschrift

To a solution of 15 g (0.05 mole) 2-methoxy-4-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]benzaldehyde in 50 ml of pyridine are added 11 g (0.11 mole) of malonic acid and 1 g of piperidine. The solution is stirred and gradually heated to 80°. Heating and stirring are continued for 1 hour at 80°. The solution is then heated at reflux for an additional 3 hours, cooled, and evaporated at reduced pressure to obtain a residual oil which is extracted into ether. The resulting ether solution is washed with water and 1N hydrochloric acid, dried with anhydrous magnesium sulfate, filtered, and evaporated at reduced pressure to obtain a residual solid which is recrystallized from chlorobutane/hexane mixed solvent to give 10.5 g of 3-{2 -methoxy-4-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]phenyl}-2-propenoic acid having a melting point of 138°-140°.

Quelle