Which of the following amines can be prepared by Gabriel synthesis?
Which of the following reactions are correct?
Under which of the following reaction conditions, aniline gives p-nitro derivative as the major product?
Which of the following reactions belong to electrophilic aromatic substitution?
What is the role of $\mathrm{HNO}_3$ in the nitrating mixture used for nitration of benzene?
$\mathrm{HNO}_3$ acts as a base in the nitrating mixture and provide the electrophile, $\mathrm{NO}_2^{+}$on reaction with $\mathrm{H}_2 \mathrm{SO}_4$ as follows
$$\mathrm{\mathop {HN{O_3}}\limits_{Base} + \mathop {{H_2}S{O_4}}\limits_{Acid} \buildrel {} \over \longrightarrow \mathop {{H_2}N{O_3}}\limits_{conjugate\,acid} + HSO_4^ - \buildrel {} \over \longrightarrow \mathop {NO_2^ + }\limits_{Electrophile} + HSO_4^ - + {H_2}O}$$
