反应详情

温度

0 °C

A 0.25M THF solution of tert-butyl acetate (2.90 g, 25 mmol) is added dropwise to a cold (−78° C.) solution of potassium bis(trimethylsilyl)amide (100 ml of a 0.5M toluene solution) and ethyl 5-chlorothiophene-2-carboxylate (Lancaster)(4.77 g, 25 mmol) in 50 ml of THF. The reaction is allowed to warm to 0° C. over one hour. After stirring an additional hour at 0° C., the reaction is poured into 100 ml of a 1M HCl solution. The organic layer is extracted with brine and evaporated in vacuo. The crude residue is purified by flash column chromatography eluting with 5% ethyl acetate/hexane to provide the product (4.54 g, 17 mmol) as an oil. 1H NMR (CDCl3, 300 MHz) δ7,53 (d, 1H), 6.98 (d, 1H), 3.78 (3, 2H), 1.50 (s, 9H).

1. extractionThe organic layer is extracted with brine
2. customevaporated in vacuo
3. customThe crude residue is purified by flash column chromatography
4. washeluting with 5% ethyl acetate/hexane