Question

Decreasing order of rate of electrophilic aromatic substitution is:

• A. $a>b>c>d$
• B. $a>c>b>d$
• C. $b>a>c>d$
• D. $b>c>a>d$

Answer 1

Answer: (A)

$a>b>c>d$

(a) has 3 methyl groups and all are activators for EAS. there are 3 positions available for substitution and so has highest rate

(b) and (c) both have 2 Me groups but in (b) they support each other for EAS and there are 4 sites available . So (b) has higher rate than (c).

And (d) has only one activating group thus has lowest rate