Question

Which of these will produce the highest yield in Friedel-Craft’s reaction?

• A.

  

• B.

  

• C.

  

• D.

  

Answer 1

The correct option is C

The explanation for the correct option:

Option C:

1. Here, the ${\mathrm{CONH}}_2$ group's M effect causes an electron displacement from the ring to the group.
2. The ring is quite inactive.
3. In the Friedel-Crafts process, we employ ${\mathrm{AlCl}}_3$ as a catalyst.
4. Because both phenol and aniline will produce the deactivated ring, none undergo the Friedel-Craft process.
5. Due to the chlorine's +M action, electrons are displaced from the group to the ring.
6. As a result, the Friedel-Craft process will generate the maximum yield when chlorobenzene is used.

The explanation for the incorrect options:

Options A, B, and D:

1. Only aniline and phenol have substantial +R effects, but aniline is a Lewis base, which means it can react with a Lewis acid introduced during the reaction.
2. As a result, in Friedel-reaction, Craft's phenol produces the lowest yield.