On on heating diethyl ether with conc- HI, 2 moles of which of the following is formed

On on heating diethyl ether with conc- HI, 2 moles of which of the following is formed
  1. Ethanol
  2. Iodoform
  3. Ethyl iodide
  4. Methyl iodide

Solution

Firstly the HI given will get ionized:
$\mathrm{Hl} ightarrow \mathrm{H}^{+}+\mathrm{I}^{-}$
The iodide ion produced will attack one of the Carbon-oxygen bonds, gets attached to carbon, the hydrogen ion produced in the first step will get attached to a negatively charged oxygen atom:
$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{O}-\mathrm{CH}_{2} \mathrm{CH}_{3}+\mathrm{HI} ightarrow \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OH}+\mathrm{I}-\mathrm{CH}_{2}-\mathrm{CH}_{3}$
The ethanol produced in the above step still has a carbon-oxygen bond and we are provided with an excess of HI (concentrated), so the iodide ion will now attack the carbon-oxygen bond of ethanol similarly, and the hydrogen ion will get attached to hydroxide ion produced:
$\mathrm{CH}_{3} \mathrm{CH}_{2}-\mathrm{OH}+\mathrm{HI} ightarrow \mathrm{CH}_{3} \mathrm{CH}_{2}-\mathrm{I}+\mathrm{H}_{2} \mathrm{O}$
Thus, the overall reaction between diethyl ether and hot and concentrated HI will be:
$\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{OCH}_{2} \mathrm{CH}_{3}+2 \mathrm{Hl} ightarrow 2 \mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{I}+\mathrm{H}_{2} \mathrm{O}$
Means, the given reaction will give two moles of ethyl iodide. *

Asked in: JEE-TOPICTESTS-CHEMISTRY

Practice more HALOALKANES AND HALOARENES questions on Aicharya