Question

Benzene is heated with a mixture of concentrated $HN{O}_3$ and concentrated $H_{2}S{O}_4$ at ${60}^{o}C.$ The product of this reaction is then treated with $C{l}_2$ in the presence of anhydrous $FeC{l}_3.$ The major product obtained in the final step is

• A. 2-chloro-1-nitrobenzene
• B. 3-nitrochlorobenzene
• C. 4-chloro-1-nitrobenzene
• D. equal amounts of (A) and (C)

Answer 1

The correct option is B 3-nitrochlorobenzene

The replacement/substitution of one $H$-atom of benzene ring by nitro group $\left(N{O}_2\right)$ .It is carried out by treating benzene with conc. nitric acid and conc. sulfuric acid to form nitrobenzene.

In nitrobenzene, $-N{O}_2$ is a -R group which will reduce the electron density at ortho and para position. Thus, electrophilic attack takes place at meta position.

Thus, $C{l}^{+}$ electrophile formed from $C{l}_2$ and $FeC{l}_3$ will attack the nitrobenzene at meta position to give 3-chloro-1-nitrobenzene.