反応 #52032

反応方程式

(2,3-Dihydro-thieno[3,4-b][1,4]dioxin-2-ylmethoxy)-acetic acid ethyl ester

ethanol

Potassium hydroxide

→

(2,3-dihydro-thieno[3,4-b][1,4]dioxin-2-yl-methoxy)-acetic acid

溶媒

water

反応条件

後処理

1. 1
   その他The solvents were then removed by distillation, ethyl acetate (50 mL), ice-water (50 mL) and concentrated hydrochloric acid (5 mL)
2. 2
   workup.ADDITIONwere added
3. 3
   その他Subsequently, the organic phase was separated
4. 4
   洗浄washed with a saturated aqueous solution of sodium chloride
5. 5
   乾燥dried with anhydrous magnesium sulphate
6. 6
   濃縮concentrated
7. 7
   その他Finally the raw product was recrystallized from ethyl acetate/hexanes (1/1)
8. 8
   その他resulting in pure (2,3-dihydro-thieno[3,4-b][1,4]dioxin-2-ylmethoxy)-acetic acid

実験手順

(2,3-Dihydro-thieno[3,4-b][1,4]dioxin-2-ylmethoxy)-acetic acid ethyl ester (10.2 g, 40 mmol) was dissolved into ethanol (100 mL) and water (50 mL), blanketed by nitrogen. Potassium hydroxide (2.9 g) was added and the mixture was heated at 35° C. for 30 min. The solvents were then removed by distillation, ethyl acetate (50 mL), ice-water (50 mL) and concentrated hydrochloric acid (5 mL) were added and the mixture was vigorously stirred. Subsequently, the organic phase was separated, washed with a saturated aqueous solution of sodium chloride, dried with anhydrous magnesium sulphate and concentrated. Finally the raw product was recrystallized from ethyl acetate/hexanes (1/1) resulting in pure (2,3-dihydro-thieno[3,4-b][1,4]dioxin-2-ylmethoxy)-acetic acid as demonstrated by NMR and mass spectroscopy.

出典