Urea → Benzene, 1,3-dichloro-2-iodo-5-nitro-

Beteiligte Stoffe

Reaktionsschritte

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°.

Herkunft & Nachweise