Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R) : Assertion (A) : \(\mathrm{S}_{\mathrm{N}} 2\) reaction of \(\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{CH}_{2} \mathrm{Br}\) occurs more readily than the \(\mathrm{S}_{\mathrm{N}} 2\) reaction of \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{Br}\). Reason (R) : The partially bonded unhybridized p-orbital that develops in the trigonal bipyramidal transition state is stabilized by conjugation with the phenyl ring. In the light of the above statements, choose the most appropriate answer from the options given below :

(C) Both (A) and (R) are correct and (R) is the correct explanation of (A)

(A) (A) is not correct but (R) is correct

(B) Both (A) and (R) are correct but (R) is not the correct explanation of (A)

(D) (A) is correct but (R) is not correct

JEE Main · 2024 · 09 Apr 2024 · Shift 1 · Haloalkanes and Haloarenes

Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R) :

Assertion (A) :

S_{N} 2

reaction of

C_{6} H_{5} CH_{2} Br

occurs more readily than the

S_{N} 2

reaction of

CH_{3} CH_{2} Br

.

Reason (R) : The partially bonded unhybridized p-orbital that develops in the trigonal bipyramidal transition state is stabilized by conjugation with the phenyl ring.

In the light of the above statements, choose the most appropriate answer from the options given below :

(A)(A) is not correct but (R) is correct
(B)Both (A) and (R) are correct but (R) is not the correct explanation of (A)
(C)Both (A) and (R) are correct and (R) is the correct explanation of (A)✓ Correct
(D)(A) is correct but (R) is not correct

Answer: (C)

Solution

Benzyl bromide undergoes S_N2 faster than ethyl bromide (A correct): the partially bonded p-orbital in the transition state is stabilised by conjugation with the phenyl ring (R correct and is the explanation). Option (3).

JEE Main · 2024 · 09 Apr 2024 · Shift 1 · Single correct option

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JEE Main · 2024 · 09 Apr 2024 · Shift 1 · Haloalkanes and Haloarenes

Solution

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