反応 #554605

反応方程式

lithium hydroxide trihydrate

ethanol

ethyl acetate

Ethyl 4,6-dibromo-3-(3-ethoxy-3-oxopropyl)-1H-indole-2-carboxylate

→

3-(2-Carboxyethyl)-4,6-dibromo-1H-indole-2-carboxylic acid

収率 95.0%

溶媒

hexane

THF

water

methanol

—

petrol ether

water

tetrahydrofurane

反応条件

後処理

1. 1
   workup.STIRRINGto stir at rt for 24 h
2. 2
   その他was removed under reduced pressure
3. 3
   抽出the product was extracted with diethyl ether (3×30 ml)
4. 4
   乾燥The organic layers were dried over magnesium sulfate
5. 5
   ろ過filtered
6. 6
   その他evaporated to dryness
7. 7
   その他to yield a light-beige-colored solid in 95-100% yield

実験手順

Ethyl 4,6-dibromo-3-(3-ethoxy-3-oxopropyl)-1H-indole-2-carboxylate (4.47 g, 10 mmol) was dissolved in 25 ml tetrahydrofurane (THF) with stirring at rt. Then a solution of 1.26 g of lithium hydroxide trihydrate (3 equiv.) in 25 ml water was added and the resulting mixture was let to stir at rt for 24 h. After completion of the reaction THF was removed under reduced pressure and the pH was adjusted to 4-5, and the product was extracted with diethyl ether (3×30 ml). The organic layers were dried over magnesium sulfate, filtered, and evaporated to dryness to yield a light-beige-colored solid in 95-100% yield. mp. 259° C.; well soluble in methanol, ethanol and ethyl acetate; slightly soluble in petrol ether, water, hexane. 1H-NMR (MeOH-d4): δ 2.67 (t, 2H, 3J=8.4 Hz, CH2); 3.71 (t, 2H, 3J=8.4 Hz, CH2); 7.42 (d, 1H, 4J=1.6 Hz, C7-H); 7.62 (d, 1H, 4J=1.6 Hz, C5-H). 13C-NMR (MeOH-d4): δ 21.4 (C-2′); 37.9 (C-1′); 115.9 (C-7); 117.0 (C-4); 118.8 (C-6); 123.9 (C-3); 125.5 (C-2); 127.9 (C-3a); 128.2 (C-5); 139.6 (C-7a); 164.6 (2′-CO2H); 170.1 (2-CO2H). LC-MS (m/z): 392.0 [M]+; 390.0 [M]−. Purity (LC-MS): 99%.

出典