Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).…
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 :
(A) is correct but (R) is not correct
(A) is not correct but (R) is correct
Both (A) and (R) are correct but (R) is not the correct explanation of (A)
Both (A) and (R) are correct and (R) is the correct explanation of \((\mathbf{A})\)
Solution
The benzyl group acts in much the same way using the $\pi$-system of the benzene ring for conjugation with the p-orbital in the transition state.
