反応 #1910447

反応方程式

triethylamine

chloro(2-chloro(3-pyridyl))(hydroxyimino)methane

methyl-2-butynoate

→

isoxazole

3-(2-Chloro-pyridin-3-yl)-5-methyl-isoxazole-4-carboxylic acid methyl ester

溶媒

diethyl ether

diethyl ether

反応条件

後処理

1. 1
   温度Cool the mixture in an ice bath under a nitrogen atmosphere
2. 2
   その他Quench the mixture with water
3. 3
   抽出extract with diethyl ether
4. 4
   濃縮Concentrate the combined extracts
5. 5
   洗浄elute over silica gel with 10% methanol/dichloromethane

実験手順

Combine chloro(2-chloro(3-pyridyl))(hydroxyimino)methane (2.90 g, 0.015 mol) with methyl-2-butynoate (1.19 mL, 0.012 mol) in diethyl ether (75 mL). Cool the mixture in an ice bath under a nitrogen atmosphere. Add a solution of triethylamine (1.77 mL, 0.013 mol) in diethyl ether (10 mL) in a dropwise manner. Stir the mixture overnight while warming to ambient temperature. Quench the mixture with water and extract with diethyl ether. Concentrate the combined extracts and elute over silica gel with 10% methanol/dichloromethane to give the desired isoxazole along with a co-eluting impurity (2.30 g, 60%). MS(ES): (M+1)+ 253.0, 255.0 m/z.

出典