Reacción #2028890

Ecuación de reacción

4-[5-(4-chlorophenyl)-3-trifluoromethyl-1H-pyrazol-1-yl]benzenesulfonamide

acetic acid

chlorine

→

4-[5-(4-chlorophenyl)-4-chloro-3-trifluoromethyl-1H-pyrazol-1-yl]benzenesulfonamide

Rendimiento 75.0%

Disolventes

water

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroA 100 mL three-necked round-bottomed flask equipped
2. 2
   Temperaturawith reflux condenser, gas dispersion tube
3. 3
   workup.STIRRINGThe solution was stirred at room temperature
4. 4
   workup.STIRRINGThe solution was then stirred at room temperature for 1.25 hours
5. 5
   ExtracciónThe solution was then extracted three times with ether
6. 6
   Lavadothe combined ethereal phase washed with brine
7. 7
   Secadodried over MgSO4
8. 8
   Filtraciónfiltered
9. 9
   Concentraciónconcentrated in vacuo
10. 10
    Otroto give a white solid
11. 11
    Otrothat was recrystallized from ether/petroleum ether

Procedimiento

A 100 mL three-necked round-bottomed flask equipped with reflux condenser, gas dispersion tube and provisions for magnetic stirring was charged with 4-[5-(4-chlorophenyl)-3-trifluoromethyl-1H-pyrazol-1-yl]benzenesulfonamide (Example 1) (500 mg, 1.2 mmol) and 50 mL of glacial acetic acid. The solution was stirred at room temperature and treated with a stream of chlorine gas for a period of 15 minutes. The solution was then stirred at room temperature for 1.25 hours and then diluted with 100 mL of water. The solution was then extracted three times with ether and the combined ethereal phase washed with brine, dried over MgSO4, filtered, and concentrated in vacuo to give a white solid that was recrystallized from ether/petroleum ether to provide 390 mg (75%) of 4-[5-(4-chlorophenyl)-4-chloro-3-trifluoromethyl-1H-pyrazol-1-yl]benzenesulfonamide: mp 180°-182° C.; 1H NMR (CDCl3/300 MHz) 7.97 (d, J=6.6Hz, 2H, 7.49 (d, 2H), 7.45 (d, J=6.3Hz, 2H), 7.25 (d, J=6.6Hz, 2H), 5.78 (brs, 2H).

Fuente