Question

What is the action of the following on isopropyl methyl ether? 
a. Cold HI
b. Hot HI

Answer 1

1. Action of cold HI on isopropyl methyl ether:
   When isopropyl methyl ether (mixed ether) is reacted with cold and conc. HI, methyl iodide (lower alkyl halide) and isopropyl alcohol (higher alcohol) is formed.
   \[\ce{\underset{\text{Isopropyl methyl ether}}{(CH_3)_2CH-O-CH_3} + \underset{\text{conc.}}{HI} ->[cold/273 K] \underset{\text{Isopropyl alcohol}}{(CH_3)_2CH-OH} + \underset{\text{Methyl iodide}}{CH_3-I}}\]
2. Action of hot HI on isopropyl methyl ether:
   When isopropyl methyl ether (mixed ether) is reacted with hot and conc. HI at about 373 K, a mixture of isopropyl iodide and methyl iodide is obtained due to cleavage of both C - O bond.
   \[\ce{ \underset{\text{Isopropylmethylether}}{(CH_3)_2- CH-O-CH_3} + \underset{\text{conc.}}{2HI} ->[Hot/373 K] \underset{\text{Isopropyl iodide}}{(CH_3)_2-CH-I} + \underset{\text{Methyl iodide}}{CH_3-I} + H_2O}\]