반응 #10364

반응 방정식

NaHCO3

ethanol

2,3,4,5-tetrafluorobenzoic acid

oxalyl chloride

→

title compound

수율 100.3%

2,3,4,5-Tetrafluorobenzoic acid ethyl ester

수율 100.3%

용매

dichloromethane

반응 조건

후처리

1. 1
   workup.WAITat room temperature for 1.5 hours
2. 2
   농축The mixture is concentrated to dryness
3. 3
   workup.ADDITIONThe resulting acid chloride is diluted with dichloromethane (50 mL)
4. 4
   온도cooled to 0° C.
5. 5
   workup.STIRRINGThe resulting solution is stirred at room temperature for 4.5 hours
6. 6
   추출extracted with chloroform
7. 7
   세척The combined organic extracts are washed with brine
8. 8
   건조dried over Na2SO4
9. 9
   여과filtered
10. 10
    농축concentrated under vacuum

실험 절차

A solution of 2,3,4,5-tetrafluorobenzoic acid (4.68 g, 24.1 mmol) in dichloromethane (50 mL) at 0° C. is treated with oxalyl chloride (11.5 mL, 132 mmol) followed by N,N-dimethylformamide (4 drops). The mixture is stirred at 0° C. for 5 minutes and then at room temperature for 1.5 hours. The mixture is concentrated to dryness and subsequently co-evaporated from benzene. The resulting acid chloride is diluted with dichloromethane (50 mL), cooled to 0° C., and anhydrous ethanol (15.0 mL, 256 mmol) is added dropwise. The resulting solution is stirred at room temperature for 4.5 hours, then poured into saturated NaHCO3 and extracted with chloroform. The combined organic extracts are washed with brine, dried over Na2SO4, filtered, and concentrated under vacuum to afford the title compound (5.37 g). 1H NMR (CDCl3): δ 7.67–7.55 (m, 1H), 4.42 (q, 2H), 1.41 (t, 3H).

출처