反应详情

A solution of benzothioamide (4.0 g, 29.2 mmol) in THF (80 mL) was treated dropwise with ethyl bromopyruvate (7.6 g, 39 mmol) and heated at reflux for 18 hours. The reaction was then concentrated under vacuum, diluted with ethyl acetate, washed with water (1×), brine (1×) and dried over anhydrous magnesium sulfate. The residue obtained after concentration was purified by silica gel chromatography (4.5×11 cm, 20% AcOEt/toluene), followed by a second purification with 20% AcOEt/hexane. The title material was obtained after concentration as a yellow oil (5.25, 77%). 1H NMR (CDCl3, 400 MHz): 8.14 (s, 1H) 8.00 (m, 2H) 7.46-7.42 (m, 3H) 4.43 (q, J=7.0 Hz, 2H) 1.42 (t, J=7.3 Hz, 3H).

1. temperatureheated
2. temperatureat reflux for 18 hours
3. concentrationThe reaction was then concentrated under vacuum
4. additiondiluted with ethyl acetate
5. washwashed with water (1×), brine (1×)
6. dry with materialdried over anhydrous magnesium sulfate
7. customThe residue obtained
8. concentrationafter concentration
9. customwas purified by silica gel chromatography (4.5×11 cm, 20% AcOEt/toluene)
10. customfollowed by a second purification with 20% AcOEt/hexane