Question

Arrange the following compounds in their increasing SIR (Steric Inhibition of Resonance) effect order :

• A. D < B < C < A
• B. A < B < C < D
• C. C < B < A < D
• D. D < C < B < A

Answer 1

The correct option is B A < B < C < D

Bulkier the group at ortho position, more is the SIR (Steric Inhibition of Resonance) .
Since order of bulkiness :
$F<Cl<Br<I$
The Steric Inhibition of Resonance follows the same order
The correct option is (b)