Reacción #63565

Ecuación de reacción

urea

Potassium iodide

sodium nitrite

2,6-dichloro-4-nitroaniline

→

3,5-dichloro-4-iodonitrobenzene

Rendimiento 86.0%

Disolventes

water

sulphuric acid

acetic acid

Condiciones de reacción

Tratamiento posterior

1. 1
   Otrothe reaction mixture below 22°
2. 2
   workup.ADDITIONpoured slowly
3. 3
   Otrothe mixture below 23°
4. 4
   workup.STIRRINGwith stirring
5. 5
   workup.STIRRINGthe mixture stirred at room temperature for 3 hours
6. 6
   FiltraciónThe product was filtered off
7. 7
   Lavadowashed with water
8. 8
   Otrothen triturated with hot ethanol

Procedimiento

To a stirred suspension of 2,6-dichloro-4-nitroaniline (200 g) in glacial acetic acid (1.3 l) at 16° was added dropwise a solution of sodium nitrite (93.84 g) in concentrated sulphuric acid (500 ml), keeping the reaction mixture below 22°. The reaction mixture was stirred and kept below this temperature for 0.5 hour, then poured slowly onto crushed ice/water (2.5 liters) containing urea (31.71 g), keeping the mixture below 23°. Potassium iodide (225.77 g) in water (600 ml) was slowly added with stirring and the mixture stirred at room temperature for 3 hours. The product was filtered off, washed with water then triturated with hot ethanol to give 3,5-dichloro-4-iodonitrobenzene (263.4 g, 86%) as a buff solid, m.p. 147°-150°.

Fuente