Advertisements
Advertisements
Question
Haloarenes are less reactive than haloalkanes and haloalkenes. Explain.
Advertisements
Solution
In haloarenes, the electron pairs on halogen atom are in conjugation with π-electrons of the ring.
C-Cl bond acquires a partial double bond character due to resonance. As a result, the bond cleavage in haloarene is difficult than haloalkane and therefore, they are less reactive towards nucleophilic substitution reaction.
APPEARS IN
RELATED QUESTIONS
Chlorobenzene is extremely less reactive towards a nucleophilic substitution reaction. Give two reasons for the same.
Write the final product(s) in each of the following reactions:
The presence of nitro group (−NO2) at o/p positions increases the reactivity of haloarenes towards nucleophilic substitution reactions.
How the following conversion can be carried out?
Chlorobenzene to p-nitrophenol
Write the product formed on reaction of D-glucose with Br2 water.
What is Grignard reagent?
Assertion: Presence of a nitro group at ortho or para position increases the reactivity of haloarenes towards nucleophilic substitution.
Reason: Nitro group, being an electron-withdrawing group decreases the electron density over the benzene ring.
Which of the following compounds will give racemic mixture on nucleophilic substitution by \[\ce{OH-}\] ion?
(a) \[\begin{array}{cc}
\phantom{}\ce{CH3 - CH - Br}\\
\phantom{}|\\
\phantom{....}\ce{C2H5}\phantom{}
\end{array}\]
(b) \[\begin{array}{cc}
\phantom{..}\ce{Br}\\
\phantom{}|\\
\phantom{}\ce{CH3 - C - CH3}\\
\phantom{}|\\
\phantom{....}\ce{C2H5}\phantom{}
\end{array}\]
(c) \[\begin{array}{cc}
\phantom{....}\ce{CH3 - CH - CH2Br}\\
\phantom{}|\\
\phantom{....}\ce{C2H5}\phantom{}
\end{array}\]
Arrange the following compounds in increasing order of rate of reaction towards nucleophilic substitution.
| (a) |  |
| (b) |  |
| (c) |  |
Arrange the following compounds in increasing order of rate of reaction towards nucleophilic substitution.
| (a) |  |
| (b) |  |
| (c) |  |
Arrange the following compounds in increasing order of rate of reaction towards nucleophilic substitution.
| (a) |  |
| (b) |  |
| (c) |  |
\[\ce{C6H12O6 ->[(Zymase)] A ->[NaOH][\Delta] B + CHI3}\]
The number of carbon atoms present in the product B is:
Why haloarenes are not reactive towards nucleophilic substitution reaction? Give two reactions.
In the reaction, \[\mathrm{CH}_3\mathrm{C}\equiv\mathrm{\overline{C}Na}^++(\mathrm{CH}_3)_2\mathrm{CHCl}\to\] the product formed is ______.
Identify the final product [D] obtained in the following sequence of reactions.
\[\ce{CH3CHO \underset{ii) H2O+}{\overset{i) LiAlH4}{->}} [A] \underset{\triangle}{\overset{H2SO4}{->}} [B]}\]
