反应详情

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.

1. concentrationconcentrated by evaporation
2. additionThe residue was diluted with water
3. washwashed with ether
4. extractionextracted with ethyl acetate
5. dry with materialThe extracts were dried (MgSO4)
6. customevaporated