Reaktion #64652

Reaktionsgleichung

ethyl α-methylenebenzenepropanoate

potassium hydroxide

→

title compound

Ausbeute 71.0%

α-methylenebenzenepropanoic acid

Ausbeute 71.0%

Lösungsmittel

methanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Einengenconcentrated by evaporation
2. 2
   workup.ADDITIONThe residue was diluted with water
3. 3
   Waschenwashed with ether
4. 4
   Extraktionextracted with ethyl acetate
5. 5
   TrocknenThe extracts were dried (MgSO4)
6. 6
   Sonstigeevaporated

Vorschrift

The ethyl α-methylenebenzenepropanoate of Step 8 (4.6 g, 24.3 mmol) was dissolved in methanol (12 mL) and then reacted with 2N potassium hydroxide (24 mL) solution. The mixture was stirred at room temperature for 4 hours and concentrated by evaporation. The residue was diluted with water and washed with ether. The aqueous layer was acidified to pH 2 with 1N HCl, and then extracted with ethyl acetate. The extracts were dried (MgSO4) and evaporated to give the title compound as colorless oil (2.8 g, 66% yield). 1H NMR: 300MHz spectrum consistent with proposed structure.

Quelle