JEE Challenger
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Directive Influence in Bromination of Bromobenzene

STATEMENT-1 : Bromobenzene upon reaction with Br2/Fe\text{Br}_2/\text{Fe} gives 1,4-dibromobenzene as the major product.
and
STATEMENT-2 : In bromobenzene, the inductive effect of the bromo group is more dominant than the mesomeric effect in directing the incoming electrophile.

Options

A

STATEMENT-1 is True, STATEMENT-2 is True; STATEMENT-2 is a correct explanation for STATEMENT-1

B

STATEMENT-1 is True, STATEMENT-2 is True; STATEMENT-2 is NOT a correct explanation for STATEMENT-1

C

STATEMENT-1 is True, STATEMENT-2 is False

Correct
D

STATEMENT-1 is False, STATEMENT-2 is True

Step-by-Step Solution

To evaluate the given statements:

  1. Analysis of STATEMENT-1:
    Bromobenzene undergoes electrophilic aromatic substitution when treated with Br2/Fe\text{Br}_2/\text{Fe} (which generates FeBr3\text{FeBr}_3 in situ as the Lewis acid catalyst to form the electrophile Br+\text{Br}^+).
    The bromine atom present on the benzene ring is an ortho/para-directing group. Due to steric hindrance at the ortho-position, substitution preferentially takes place at the para-position, yielding 1,4-dibromobenzene as the major product and 1,2-dibromobenzene as the minor product.
    Therefore, STATEMENT-1 is True.

  2. Analysis of STATEMENT-2:
    Halogens attached to an aromatic ring exhibit two competing electronic effects:

    • A strong electron-withdrawing inductive effect (−I-I effect) through the σ\sigma-bond framework.

    • An electron-donating resonance/mesomeric effect (+M+M effect) via delocalization of the lone pair of electrons on the halogen into the π\pi-system.

    • Reactivity: The inductive withdrawal (−I-I) is stronger than the mesomeric release (+M+M), which causes net deactivation of the benzene ring toward electrophilic attack compared to benzene.

    • Directive Influence (Orientation): The incoming electrophile attacks preferentially at the ortho and para positions because the carbocation (arenium ion) intermediates formed by ortho and para attacks are uniquely stabilized by the +M+M resonance donation of the halogen's lone pair, giving an especially stable octet-complete contributing structure. Hence, the mesomeric effect (+M+M) dominates in directing the incoming electrophile, not the inductive effect.

    Therefore, STATEMENT-2 is False.

Conclusion:
STATEMENT-1 is True, STATEMENT-2 is False.

Hence, the correct option is C.