Question

What happens when iodobenzene is heated with copper powder in a sealed tube?

Answer 1

When iodobenzene is heated with copper powder in a sealed tube, the following occurs:

1. Copper metal reacts with iodobenzene (C₆H₅I) on heating to form phenylcopper (C₆H₅Cu).
2. This reaction involves the replacement of the iodine atom by copper.
3. The reaction can be represented by the equation:
   \[\mathrm{C_6H_5} + 2 \mathrm{Cu} \xrightarrow{\Delta, \text{sealed tube}} \mathrm{C_6H_5Cu} + \mathrm{2CuI}\]
4. Here, phenylcopper is formed along with copper(I) iodide (CuI) as a byproduct.
5. This is an example of the preparation of organometallic compounds by direct reaction of aryl halides with copper powder at elevated temperature.
6. The sealed tube maintains the required temperature and pressure conditions for the reaction to proceed.