反応 #43726

反応方程式

methyl chloroacetate

2-hydroxy-5-nitrobenzaldehyde

potassium carbonate

hydrochloric acid

potassium hydroxide

→

title compound

7-Nitro-1-benzofuran-2-carboxylic acid

溶媒

water

THF

反応条件

後処理

1. 1
   抽出The mixture is extracted with ethyl acetate
2. 2
   洗浄The organic phase is washed with water
3. 3
   乾燥dried over sodium sulfate
4. 4
   workup.ADDITIONAfter the addition of silica gel
5. 5
   濃縮the mixture is concentrated
6. 6
   その他chromatographed on silica gel (mobile phase gradient: toluene to toluene/methanol/glacial acetic acid 35:5:1)
7. 7
   その他Concentration of the product fractions and drying under reduced pressure

実験手順

3.0 g (17.9 mmol) of 2-hydroxy-5-nitrobenzaldehyde, 0.66 g (1.80 mmol) of tetra-N-butylammonium iodide and 9.92 g (71.81 mmol) of potassium carbonate are mixed, 4.09 g (37.7 mmol) of methyl chloroacetate are added and the mixture is heated at 130° C. for 4 h. 35 ml of THF and, with ice cooling, 6.04 g (107.71 mmol) of potassium hydroxide are added. Following the addition of 50 ml of water, the mixture is stirred at RT for 20 h. Using concentrated hydrochloric acid, the pH is adjusted to 0. The mixture is extracted with ethyl acetate. The organic phase is washed with water and dried over sodium sulfate. After the addition of silica gel, the mixture is concentrated and chromatographed on silica gel (mobile phase gradient: toluene to toluene/methanol/glacial acetic acid 35:5:1). Concentration of the product fractions and drying under reduced pressure gives 2.00 g (54% of theory) of the title compound.

出典