반응 #1102848

반응 방정식

t-butanol

magnesium sulfate

H2SO4

bicarbonate

3-Iodo-5-phenyl-thiophene-2-carboxylic acid

→

3-Iodo-5-phenyl-thiophene-2-carboxylic acid tert-butyl ester

수율 44.1%

용매

dichloromethane

반응 조건

후처리

1. 1
   여과filtered
2. 2
   세척The solid was washed with CH2Cl2
3. 3
   기타the filtrate dried
4. 4
   농축concentrated to an oil
5. 5
   기타The crude material was purified by flash chromatography

실험 절차

A suspension of magnesium sulfate (4.61 g, 38.32 mmol) in dichloromethane (37 ml) at 21° C., under N2, was treated with conc H2SO4 (510 μl, 9.58 mmol). After 15 min solid 3-Iodo-5-phenyl-thiophene-2-carboxylic acid (3.7 g, 9.58 mmol) was added followed by t-butanol (4.55 ml, 47.9 mmol) and the flask was stoppered and left over-night for 19.5 h. The reaction mixture was treated with saturated bicarbonate aqueous solution, and filtered. The solid was washed with CH2Cl2 and the filtrate dried and concentrated to an oil. The crude material was purified by flash chromatography using Hexane/CH2Cl2 (3:1) as eluent to give 1.63 g (44%) of 3-Iodo-5-phenyl-thiophene-2-carboxylic acid tert-butyl ester as a colorless solid. NMR 1H (CDCl3, 400 MHz) 7.61-7.59 (m, 2H); 7.43-7.35 (m, 3H), 7.25 (s, 1H), 1.60 (bs, 9H).

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