反応 #80972

反応方程式

2-methylpropane-thioamide

ethyl bromopyruvate

MgSO4

→

desired compound

収率 86.4%

Ethyl 2-Isopropylthiazole-4-carboxylate

収率 86.4%

溶媒

acetone

反応条件

後処理

1. 1
   温度heated
2. 2
   温度at reflux for 2.5 h
3. 3
   温度to cool
4. 4
   ろ過filtered
5. 5
   濃縮concentrated in vacuo to an oil, which
6. 6
   洗浄washed sequentially with aqueous NaHCO3 and brine
7. 7
   乾燥dried over Na2SO4
8. 8
   濃縮concentrated
9. 9
   その他The residue was purified by chromatography on silica gel

実験手順

A solution of 2.35 g (23 mmol) of 2-methylpropane-thioamide and 2.89 ml (23 mmol) of ethyl bromopyruvate in 75 ml of acetone was treated with excess MgSO4 and heated at reflux for 2.5 h. The resulting mixture was allowed to cool, filtered, and concentrated in vacuo to an oil, which was taken up in chloroform, washed sequentially with aqueous NaHCO3 and brine, dried over Na2SO4, and concentrated. The residue was purified by chromatography on silica gel using chloroform as an eluent to provide 3.96 g (86%) of the desired compound, Rf 0.21 (chloroform) as an oil. 1H NMR (CDCl3) δ1.41 (t, J=8 Hz, 3H), 1.42 (d, J=7 Hz, 6H), 3.43 (heptet, J=7 Hz, 1H), 4.41 (q, J=8 Hz, 2H), 8.05 (s, 1H). Mass spectrum: (M+H)+ =200.

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