Class 12th Chemistry 2017 Set2 Delhi Board Paper Solution
Give reasons:
Although - NH2 is o/p directing group, yet aniline on nitration gives a significant amount of m-nitroaniline.
Nitration is usually carried out with a mixture of conc.HNO3 and conc. H2SO4. So in the presence of these acids, aniline gets protonated to form anilinium ion. Therefore, the reaction mixture consists of aniline and anilinium ion. - NH2 group in aniline is o, p-directing and activating, whereas the NH3 group in anilinium is m-directing and deactivating. Now, nitration of aniline mainly gives p-nitroaniline due to steric hindrance at o-position and the nitration of anilinium ion gives m -nitroaniline.
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