Benzene and Alkyl Benzene - Result Question 32
####36. Explain the followings :
(a) (i)
(ii)
(d)
(2005)
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Solution:
- (a) (i)
(b) (i)
Nitro group from para position activate aromatic nucleophilic substitution.
(ii)
$-NO _2$ is not in resonance with benzene ring, does not activate the aromatic nucleophilic substitution reaction, hence fluoride is not formed. (c) (i)
Hence, $-NO$ is ortho/para directing although deactivating group. Therefore, ortho/para nitro derivatives are formed on treatment with mixed acid.
(ii)
Nitro group is meta directing as well as strongly deactivating.
(d)
In the above hydrogenation reaction, the anti-aromatic character of three cyclobutadiene rings are relieved that provide stability to the hydrogenation product.
