Question

When glycerol is heated with a large amount of HI or $P{I}_3,$ the product obtained is:

• A. Glycerol triiodide
• B. Allyl iodide
• C. 2-Iodopropane
• D. None

Answer 1

The correct option is C 2-Iodopropane

When glycerol is treated with an excess of $HI$, it produces 2-iodopropane.

In the first step, a molecule of glycerol reacts with 3 $HI$ molecules to form unstable 1,2,3-triiodopropane. This loses a molecule of iodine to form allyl iodide.
Allyl iodide adds a molecule of $HI$ to obtain an unstable molecule which loses a molecule of iodine to form propene.

A molecule of $HI$ is added to propene to form 2-iodopropane.

Hence, the correct option is (A).