Reaktion #42332

Reaktionsgleichung

sodium bicarbonate

Isovalerothioamide

ethyl formylchloroacetate

water

→

desired product

5-Hydroxymethyl-2-(2-methylpropyl)thiazole

Lösungsmittel

DMF

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction is subsequently cooled to 0 degrees C
2. 2
   Extraktionextracted with ether (3×35 mL)
3. 3
   WaschenThe combined organic extracts are washed with water
4. 4
   Trocknensaline and dried over magnesium sulfate
5. 5
   Filtrationfiltered
6. 6
   Einengenconcentrated
7. 7
   SonstigeThe residue is purified by flash chromatography (ethyl acetate/hexanes 4-10% elution)

Vorschrift

Isovalerothioamide (6.0 g, 51 mmol) and ethyl formylchloroacetate (Heterocycles 32 (4), 693-701, (1991), 5.0 g, 33 mmol) are dissolved in dry DMF (20 mL), and heated to 95 degrees C. for 4 hours. The reaction is subsequently cooled to 0 degrees C., and cold water (50 mL) is added. The mixture is basified to pH=8 with solid sodium bicarbonate, then extracted with ether (3×35 mL). The combined organic extracts are washed with water, then saline and dried over magnesium sulfate, filtered, and concentrated. The residue is purified by flash chromatography (ethyl acetate/hexanes 4-10% elution) to give the desired product. NMR (CDCl3, 300 MHz) δ 8.27, 4.45-4.30, 3.70-3.50, 3.00-2.80, 2.30-2.10, 1.40-1.20, and 1.10-0.90.

Quelle