Question

Which of the following is used as a catalyst in the manufacture of toluene from benzene with \[{\rm{C}}{{\rm{H}}_{\rm{3}}}{\rm{Cl}}\] ?
A. Ni
B. Anhydrous \[{\rm{AlC}}{{\rm{l}}_{\rm{3}}}\]
C. Pd
D. Pt

Answer 1

Hint: Toluene is a methyl group substituted benzene. Its chemical formula is \[{{\rm{C}}_{\rm{6}}}{{\rm{H}}_{\rm{5}}}{\rm{C}}{{\rm{H}}_3}\] . It can be prepared from benzene. To identify the catalyst which is used for the preparation of toluene, we have to understand the use of each catalyst.

Complete Step by Step Answer:
Let’s understand the role of the nickel (Ni) catalyst in the reaction of benzene. The use of nickel catalysts in hydrogenation reactions is significant. Nickel undergoes a reaction with hydrogen in the presence of nickel catalyst to form cyclohexane. So, option A is wrong.

Palladium (Pd) is also used in the hydrogenation reaction. When a benzene ring undergoes a reaction with hydrogen in the presence of Palladium, the product is cyclohexane. Therefore, Pd does not give toluene from benzene. Therefore, C is wrong.

Platinum (Pt) is also used in the hydrogenation reaction. When a benzene ring undergoes a reaction with hydrogen in the presence of Platinum, the product is cyclohexane. Therefore, option D is wrong.

The reaction of benzene with methyl chloride (\[{\rm{C}}{{\rm{H}}_{\rm{3}}}{\rm{Cl}}\]) in the presence of anhydrous \[{\rm{AlC}}{{\rm{l}}_{\rm{3}}}\], results in the formation of toluene.
\[{{\rm{C}}_{\rm{6}}}{{\rm{H}}_{\rm{6}}} + {\rm{C}}{{\rm{H}}_{\rm{3}}}{\rm{Cl}} \overset{Anhyd AlCl_{3}}{\rightarrow} \mathop {{{\rm{C}}_{\rm{6}}}{{\rm{H}}_{\rm{5}}}{\rm{C}}{{\rm{H}}_{\rm{3}}}}\limits_{{\rm{Toluene}}} + {\rm{HCl}}\]
Hence, option B is right.

Note: Toluene is a liquid of no colour. There are many useful applications of toluene such as the making of paints, adhesives, printing processes, etc. In the medical field, it is used as veterinary medicine for the treatment of diseases in cats and dogs.