Question

Cyclohexane on chlorination gives:
A) Chloro cyclohexane
B) 1,2-dichloro cyclohexane
C) 1,4-dichloro cyclohexane
D) A mixture of all the above

Answer 1

Hint The answer is based on the basic organic chemistry reactions which involves the reactions of halogenations and in the presence of light at room temperature or at higher temperature, the substitution reaction occurs.

Complete step – by – step answer:
In the classes of organic chemistry, we have come across the topics which deal with some of the basic named reactions and also several common reactions like substitution reactions, addition reactions, elimination reactions and so on.
Let us now see what happens when cyclohexane is chlorinated.
- Cyclohexane is the six membered ring with no presence of double bonds between them and they are the cyclic alkanes.
- The alkanes are usually not reactive unless they are subjected to a high temperature or in the presence of light or treatment of very reactive chemicals.
- Usually, alkanes undergo free radical substitution reactions when subjected to UV light that is at higher temperatures.
Therefore, the free radical reactions proceed through a chain mechanism and this reaction that is chlorination of cyclohexane, usually produces one substituted product that is chloro cyclohexane and hydrochloric acid.
The reaction is as shown below,

Therefore, in the above reaction, we can see that cyclohexane on irradiation of UV light produces mono substituted products because all the carbon atoms in cyclohexane are exactly the same.

Note: Note that even the alkyl substituted aromatic compounds undergo free radical substitution reactions which is mainly free radical chain reactions in the presence of UV light that is usually at higher temperatures and this process is used for the industrial synthesis of chloroform, dichloromethane and hexachlorobutadiene.