Reaction Replacement of a Diazo-Group by Iodine

REACTION REPLACEMENT OF A DIAZO-GROUP BY IODINE Example Phenyl Iodide from Aniline 

A solution of 10 grammes of aniline in a mixture of 50 grammes of concentrated hydrochloric add and 150 grammes of water 

If a diazoiodide is heated, the diazo-group is replaced by iodine, the reaction taking place smoothly in most cases. 

The reaction is effected by diazotising the amine in a hydrochloric acid or sulphuric acid solution, and then treating it with potassium iodide. From the diazochloride or diazosulphate there is formed a diazoiodide, the reaction, in many cases, taking place at the ordinary temperature in others, on heating, as above. Since the reaction occurs without difficulty, it is used as the method of preparation of many iodides. 

The aromatic iodides possess the noteworthy property of combining with two atoms of chlorine, the iodine previously univalent becoming tri valent  

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