Beta-Propiolactone → HCID 20135581, Verbindung

Reaktionsgleichung

[Cl:1][C:2]1[C:9]([Cl:10])=[C:8]([OH:11])[CH:7]=[CH:6][C:3]=1[CH:4]=[O:5].[C:12]1(=[O:16])[O:15][CH2:14][CH2:13]1>[OH-].[Na+].CCOCC>[Cl:10][C:9]1[C:2]([Cl:1])=[C:3]([CH:4]=[O:5])[CH:6]=[CH:7][C:8]=1[O:11][CH2:14][CH2:13][C:12]([OH:16])=[O:15]

Komponenten

Versuchsvorschrift

2,3-dichloro-4-hydroxybenzaldehyde (38.2 g., 0.2 mole) is dissolved in a 10% sodium hydroxide solution (200 ml.). The solution is heated to boiling and β-propiolactone (144 g., 2.0 moles) is added dropwise at such a rate as to keep the solution boiling. During the addition 10% sodium hydroxide solution is added in portions to maintain an alkaline mixture. Then the solution is cooled and acidified. The precipitated material is dissolved in ether and the product is extracted into a 5% sodium bicarbonate solution. Acidification of the aqueous solution precipitates 3-(2,3-dichloro-4-formylphenoxy)propionic acid, which is purified by recrystallization from ethyl acetate.