Compounds undergoing Friedel-Crafts alkylation

[jolly_math]

Homework Statement

Which of the following compounds can undergo Friedel-Crafts alkylation?

Relevant Equations

Friedel-Crafts alkylation

The answer is that the 2nd, 3rd and 6th compounds can undergo Friedel-Crafts alkylation.

I don't understand why the 4th compound cannot undergo a Friedel-Crafts alkylation reaction, but the 2nd compound can. It has an activating NH2 group and a weakly deactivating Br group, and it's similar to the 2nd compound which has an activating CH3 group and a weakly deactivating Cl group – what makes it different?

Thank you.

 

[mjc123]

What happens to the NH₂ group in the presence of the Friedel-Crafts catalyst?

 

[PhysicsEnjoyer31415]

Homework Statement: Which of the following compounds can undergo Friedel-Crafts alkylation?
Relevant Equations: Friedel-Crafts alkylation

View attachment 343324
The answer is that the 2nd, 3rd and 6th compounds can undergo Friedel-Crafts alkylation.

I don't understand why the 4th compound cannot undergo a Friedel-Crafts alkylation reaction, but the 2nd compound can. It has an activating NH2 group and a weakly deactivating Br group, and it's similar to the 2nd compound which has an activating CH3 group and a weakly deactivating Cl group – what makes it different?

Thank you.

The thing is the 4th compound has a NH2 group which has a lone pair but in presence of AlCl3 a strong electrophile , the NH2 gives up its lone pair and forms NH3+ cation which is a -M group and highly deactivating, but in the 2nd compound CH3 have activating nature and cannot give any electrons so the chlorine gets removed and CH3 gets added i think

 

[PhysicsEnjoyer31415]

The thing is the 4th compound has a NH2 group which has a lone pair but in presence of AlCl3 a strong electrophile , the NH2 gives up its lone pair and forms NH3+ cation which is a -M group and highly deactivating, but in the 2nd compound CH3 have activating nature and cannot give any electrons so the chlorine gets removed and CH3 gets added i think

Im sorry but to clarify , not the chlorine on the compound