Reacción #45768

Ecuación de reacción

Ethyl 3-bromopyruvate

4-cyano-7-fluoro-5-methyl-6-phenyl-1,3-benzoxazole-2-carbothioamide

sodium hydrogencarbonate

p-toluenesulfonic acid monohydrate

→

compound

Rendimiento 91.3%

Ethyl 2-(4-cyano-7-fluoro-5-methyl-6-phenyl-1,3-benzoxazol-2-yl)-1,3-thiazole-4-carboxylate

Rendimiento 91.3%

Disolventes

toluene

water

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturaby heating
2. 2
   TemperaturaAfter cooling to room temperature
3. 3
   Temperaturaby heating
4. 4
   Temperaturaunder reflux in an oil bath at 125° C. for 15 hours
5. 5
   TemperaturaAfter cooling to room temperature
6. 6
   Extracciónfollowed by extraction with ethyl acetate (50 ml×2)
7. 7
   LavadoThe organic layer was washed with an aqueous saturated sodium hydrogencarbonate solution (50 ml) and saturated brine (50 ml)
8. 8
   Secadodried over anhydrous sodium sulfate
9. 9
   ConcentraciónAfter concentration
10. 10
    Otrothe resulting residue was purified by silica gel column chromatography (eluent, chloroform:ethyl acetate=100:1→25:1)

Procedimiento

Ethyl 3-bromopyruvate (72.2 μl, 0.518 mmol) was added to a toluene (10 ml) solution of 4-cyano-7-fluoro-5-methyl-6-phenyl-1,3-benzoxazole-2-carbothioamide (I-196-1) (124 mg, 0.398 mmol), followed by heating under reflux in an oil bath at 125° C. for 2 hours. After cooling to room temperature, p-toluenesulfonic acid monohydrate (15.2 mg, 0.080 mmol) was added to the reaction liquid, followed by heating under reflux in an oil bath at 125° C. for 15 hours. After cooling to room temperature, an aqueous saturated sodium hydrogencarbonate solution (50 ml) and water (50 ml) were added, followed by extraction with ethyl acetate (50 ml×2). The organic layer was washed with an aqueous saturated sodium hydrogencarbonate solution (50 ml) and saturated brine (50 ml), and dried over anhydrous sodium sulfate. After concentration, the resulting residue was purified by silica gel column chromatography (eluent, chloroform:ethyl acetate=100:1→25:1) to obtain the entitled compound (148 mg, 91.2%) as a pale yellow solid.

Fuente