Is it possible to prepare 4-iodo benzyl alcohol from Benzyl alcohol

Question

4-Iodo benzyl alcohol to be prepared .

How is possibility of 2 and 3 position 

 

Answer 1

Hello Deepak

 

React benzyl alcohol with molecular iodine and nitric acid to form a mixture of 2-iodobenzyl alcohol and 4-iodobenzyl alcohol products.  I have written the basic reaction below, but am unable to draw the structures since there is no chem drawing tool available on this site.

 

Ph-CH₂-OH + 1/2 I₂ + HNO₃ → 2-iodobenzyl alcohol + 4-iodobenzyl alcohol

 

2-Iodobenzyl alcohol and 4-iodobenzyl alcohol will have different solubilities in organic solvents, which allows you separate them from each other.

 

The -CH₂OH group on the benzene ring is an activating group that directs electrophiles (iodine atom) ONLY to the ortho (2nd carbon) and para (4th carbon) positions of the benzene ring.  As a result, 3-iodobenzyl alcohol CANNOT be prepared from the above reaction.