반응 #7068

반응 방정식

4,4,4-trifluoro-3-methoxy-but-2-enoic acid ethyl ester

methyl thioglycolate

H2SO4

KOH

→

title compound

수율 91.2%

3-Hydroxy-5-trifluoromethyl-thiophene-2-carboxylic acid methyl ester

수율 91.2%

용매

MeOH

H2O

MeOH

반응 조건

후처리

1. 1
   추출The mixture is extracted with EtOAc (2×250 mL)
2. 2
   세척The combined extracts are washed with saturated NaHCO3
3. 3
   추출The washings are back-extracted with EtOAc
4. 4
   세척The combined organic layers are washed with brine
5. 5
   건조dried (Na2SO4)
6. 6
   여과filtered
7. 7
   농축concentrated

실험 절차

A solution of 4,4,4-trifluoro-3-methoxy-but-2-enoic acid ethyl ester (9.6 g, 48.5 mmol) and methyl thioglycolate (4.3 mL, 48.5 mmol) in MeOH (75 mL) is cooled to 5° C. A solution of KOH (3.3 g, 58.2 mmol) in MeOH (75 mL) is then added over 30 min. The reaction mixture is stirred overnight at room temperature. The reaction mixture is then poured over a stirred mixture of ice (75 g), H2O (75 mL) and concentrated H2SO4 (4.5 mL). The mixture is extracted with EtOAc (2×250 mL). The combined extracts are washed with saturated NaHCO3. The washings are back-extracted with EtOAc. The combined organic layers are washed with brine, then dried (Na2SO4), filtered and concentrated to afford the title compound (10 g, 91%) as a brown oil which is used without further purification.

출처