Reacción #80972

Ecuación de reacción

2-methylpropane-thioamide

ethyl bromopyruvate

MgSO4

→

desired compound

Rendimiento 86.4%

Ethyl 2-Isopropylthiazole-4-carboxylate

Rendimiento 86.4%

Disolventes

acetone

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturaheated
2. 2
   Temperaturaat reflux for 2.5 h
3. 3
   Temperaturato cool
4. 4
   Filtraciónfiltered
5. 5
   Concentraciónconcentrated in vacuo to an oil, which
6. 6
   Lavadowashed sequentially with aqueous NaHCO3 and brine
7. 7
   Secadodried over Na2SO4
8. 8
   Concentraciónconcentrated
9. 9
   OtroThe residue was purified by chromatography on silica gel

Procedimiento

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.

Fuente