What is the correct order of nitration of the following compounds?
(a) $C_{6} H_{5} CH_{3}$
(b) $C_{6} H_{6}$
(c) $C_{6} D_{6}$
(d) $C_{6} T_{6}$
(e) $C_{6} H_{5} Br$
(f) $C_{6} H_{5} N + R_{3}$
(g) $C_{6} H_{5} NMe_{2}$

Question

What is the correct order of nitration of the following compounds?

(a) $C_{6} H_{5} CH_{3}$

(b) $C_{6} H_{6}$

(c) $C_{6} D_{6}$

(d) $C_{6} T_{6}$

(e) $C_{6} H_{5} Br$

(f) $C_{6} H_{5} N + R_{3}$

(g) $C_{6} H_{5} NMe_{2}$

TestHub · Accepted Answer

The rate of nitration depends on the electron-donating or electron-withdrawing nature of the substituents on the benzene ring. Electron-donating groups activate the ring and increase the rate of nitration, while electron-withdrawing groups deactivate the ring and decrease the rate of nitration. Isotopic substitution also affects the rate due to the kinetic isotope effect.

(a) $C_{6} H_{5} CH_{3}$ (Toluene): Methyl group is electron-donating, activating the ring.

(b) $C_{6} H_{6}$ (Benzene): Reference.

(c) $C_{6} D_{6}$ (d) $C_{6} T_{6}$ Have almost same as (b)

(e) $C_{6} H_{5} Br$ (Bromobenzene): Bromine is electron-withdrawing, deactivating the ring.

(f) $C_{6} H_{5} N + R_{3}$ (Phenyltrimethylammonium ion): $- NR_{3}^{+}$ is a strong electron-withdrawing group, deactivating the ring significantly.

(g) $C_{6} H_{5} NMe_{2}$ (N,N-Dimethylaniline): $- NMe_{2}$ is a strong electron-donating group, activating the ring significantly.

Chemistry - Aromatic Hydrocarbon Question with Solution | TestHub

Options:

Doubts & Discussion

Free Mock Tests