Reaktion #82138

Reaktionsgleichung

p-hydroxybenzaldehyde

acetic acid

p-Nitrophenylacetic acid

sodium hydroxide

→

α-p-Nitrophenyl-p-acetoxycinnamic Acid

Lösungsmittel

water

ethanol

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONcontaining
2. 2
   SonstigeThe resultant solution is rotary evaporated under vacuum until final conditions of 100° C. and one nm Hg
3. 3
   Temperaturmaintained for 30 minutes
4. 4
   Sonstigeequipped with a reflux condenser
5. 5
   Temperaturreflux
6. 6
   TemperaturRefluxing
7. 7
   Sonstigeis continued over the next 18 hours
8. 8
   Temperaturthe reactor is cooled to 100° C.
9. 9
   Sonstigefor one hour
10. 10
    Temperaturby cooling to 50° C.
11. 11
    Filtrationfiltered
12. 12
    workup.ADDITIONThe filtrate is added to deionized water (1500 mL)
13. 13
    Filtrationthe resultant precipitate recovered by filtration
14. 14
    ExtraktionThe precipitate is exhaustively extracted with deionized water saturated with sodium carbonate
15. 15
    FiltrationThe combined extracts are filtered
16. 16
    FiltrationThe precipitate is recovered by filtration
17. 17
    Sonstigedried at 50° C. in a forced air, convection type oven
18. 18
    workup.ADDITIONThe dried powder is added to a beaker along with carbon tetrachloride (200 mL)
19. 19
    workup.STIRRINGstirred
20. 20
    Temperaturwith heating to a boil
21. 21
    workup.ADDITIONAcetic acid (40 mL) is added to the boiling slurry
22. 22
    Temperaturto cool to room temperature (23° C.)
23. 23
    FiltrationThe product is recovered by filtration
24. 24
    Sonstigedried at 70° C. under a vacuum of 5 mm Hg to a constant weight of 39.1 grams of brilliant, light yellow colored, crystalline powder

Vorschrift

p-Nitrophenylacetic acid (0.60 moles, 108.69 grams) is added to a one liter glass beaker containing stirred aqueous sodium hydroxide solution (24.0 grams, 0.06 mole diluted with deionized water to a total volume of 600 mL) followed by heating to 60° C. The resultant solution is rotary evaporated under vacuum until final conditions of 100° C. and one nm Hg are achieved and maintained for 30 minutes. A portion (99.08 g, 0.4877 mole) of the recovered dry, white carboxylic acid sodium salt, p-hydroxybenzaldehyde (59.56 g, 0.4877 mole) and acetic acid (250 g) are added to a reactor equipped with a reflux condenser and stirred under a nitrogen atmosphere at a 145° C. reflux. Refluxing is continued over the next 18 hours after which time, the reactor is cooled to 100° C. and ethanol (300 mL) and deionized water (50 mL) are added. The resultant slurry is boiled at 89° C. for one hour followed by cooling to 50° C. and filtered. The filtrate is added to deionized water (1500 mL) and the resultant precipitate recovered by filtration. The precipitate is exhaustively extracted with deionized water saturated with sodium carbonate. The combined extracts are filtered and neutralized with concentrated aqueous hydrochloric acid inducing formation of a precipitate. The precipitate is recovered by filtration and dried at 50° C. in a forced air, convection type oven. The dried powder is added to a beaker along with carbon tetrachloride (200 mL) and stirred with heating to a boil. Acetic acid (40 mL) is added to the boiling slurry and allowed to boil. Once boiling is achieved, the slurry is allowed to cool to room temperature (23° C.) and then at 4° C. for 16 hours. The product is recovered by filtration and dried at 70° C. under a vacuum of 5 mm Hg to a constant weight of 39.1 grams of brilliant, light yellow colored, crystalline powder.

Quelle