Reaktion #54858

Reaktionsgleichung

2,5-dimethoxytetrahydrofuran

acetic acid

acetic acid

sodium acetate

glycine

→

title compound

Ausbeute 33.6%

(1-Pyrryl)acetic Acid

Ausbeute 33.6%

Lösungsmittel

toluene

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeTo a 1 liter flask fitted with a condenser, a magnetic stirrer and a nitrogen inlet tube
2. 2
   SonstigeThe system is purged with nitrogen
3. 3
   Temperatura positive nitrogen pressure is maintained
4. 4
   Temperaturthe solution is heated to reflux
5. 5
   Temperaturrefluxing
6. 6
   Sonstigeis removed under vacuum
7. 7
   Extraktionextracted with four portions of ether
8. 8
   WaschenThe ether extracts are washed with water
9. 9
   Trocknendried over anhydrous magnesium sulfate
10. 10
    Filtrationfiltered
11. 11
    Sonstigethe ether is evaporated
12. 12
    Sonstigeto yield a slurry
13. 13
    Filtrationfiltered through celite
14. 14
    Sonstigecrystallized
15. 15
    Temperaturby cooling
16. 16
    Sonstigeto give 8.41g

Vorschrift

To a 1 liter flask fitted with a condenser, a magnetic stirrer and a nitrogen inlet tube is added acetic acid (glacial, 300 ml) and sodium acetate (32.8g; 0.4 mole). The system is purged with nitrogen and a positive nitrogen pressure is maintained. Then glycine (15.0g; 0.2 mole) is added and the solution is heated to reflux. To the refluxing, clear solution is added 2,5-dimethoxytetrahydrofuran (29 ml, 0.2 mole) over a period of 2 - 3 minutes; refluxing is continued an additional 2 minutes. The reaction mixture is cooled in an ice bath and most of the acetic acid is removed under vacuum. The residue is taken up in water and extracted with four portions of ether. The ether extracts are washed with water, dried over anhydrous magnesium sulfate, filtered and the ether is evaporated to yield a slurry. The slurry is taken up into toluene, filtered through celite and crystallized by cooling to give 8.41g. (33.6%) of the title compound. M.P. 88°-90° C.

Quelle