What is the order of reactivity towards electrophilic aromatic substitution of fluorobenzene, chlorobenzene and iodobenzene?

1 Answer
Apr 18, 2018

The order of Positive Mesomeric effect #(+M)# effect follows the order #F>Cl>Br>I#

Explanation:

From the order of #+M# effect given above it turns out that the electron density in their respective halobenzene is of order

Fluorobenzene > Chlorobenzene > Iodobenzene

Hence the reactivity towards electrophilic aromatic substitution follows the same order as given above :

Fluorobenzene > Chlorobenzene > Iodobenzene

The relative rates for nitration are given below :-

https://chemistry.stackexchange.com/questions/38341/reactivity-of-chlorobenzene-and-benzene-in-electrophilic-substitutions

Organic Chemistry book by Solomons 10th edition