反応 #10366

反応方程式

3-chloro-2,4,5-trifluorobenzoic acid

oxalyl chloride

ethanol

→

title compound

収率 100.6%

3-Chloro-2,4,5-trifluorobenzoic acid ethyl ester

収率 100.6%

溶媒

dichloromethane

dichloromethane

反応条件

後処理

1. 1
   濃縮the reaction mixture is concentrated under vacuum
2. 2
   workup.DISSOLUTIONThe resulting residue is dissolved in dichloromethane (50 mL)
3. 3
   workup.WAITAfter 30 minutes
4. 4
   洗浄washed with saturated NaHCO3, water, and brine
5. 5
   乾燥The organic layer is dried over MgSO4
6. 6
   ろ過filtered
7. 7
   濃縮the filtrate is concentrated

実験手順

To a solution of 3-chloro-2,4,5-trifluorobenzoic acid (Example 20, 4.90 g, 23.3 mmol) in dichloromethane (50 mL) is added oxalyl chloride (5.1 mL, 58.2 mmol) and N,N-dimethylformamide (1 drop). After 45 minutes, the reaction mixture is concentrated under vacuum. The resulting residue is dissolved in dichloromethane (50 mL) and treated with ethanol (10 mL, 172 mmol). After 30 minutes, the reaction mixture is diluted with dichloromethane and washed with saturated NaHCO3, water, and brine. The organic layer is dried over MgSO4, filtered, and the filtrate is concentrated to afford the title compound (5.59 g). 1H NMR (CDCl3): δ 7.76–7.68 (m, 1H), 4.40 (q, 2H), 1.39 (t, 3H).

出典