Sciencemadness Discussion Board

Iodo Benzene

misdemeanor - 29-3-2006 at 11:22

Iodo benzene-yielded Benzene Diazonium Chloride but when I added Potassium Iodide In ice bath no iodo Benzene formed. Reactions Ran one after another so no decomposition of the Benzene Diazonium Chloride. So what did I do wrong?

garage chemist - 29-3-2006 at 13:32

Can you tell us more about what you have done?
I ran this reaction without the slightest problems, and isolated a good yield of iodobenzene.

The reaction (benzene diazonium chloride + KI) needs to be left to stand for about 24 hours, it doesn't hurt if you leave it to stand even longer.
Then it is slowly warmed to 50°C and held there until the nitrogen evolution has ceased entirely.
The iodobenzene separates as a black very heavy oil. If your batch was small it might be hard to see. Tilt the beaker, or decant most of the supernatant.