Question

Benzene in the presence of the acetyl chloride and alcl3

Answer 1

Classic example of Friedel Crafts' Acylation Reaction.

We get Acetophenone (C6H5COCH3) as the major product.

Now lets see the mechanism :)

AlCl3 is considered to be a Lewis Acid or in simpler words an “electron hungry species”. So, when it sees Acetyl Chloride (CH3COCl) it extracts the -Cl minus from the latter and itself gets transformed into AlCl4 minus. Now it is quite stable because his hunger has been satisfied.

Now it leaves behind an electrophile -COCH3 minus. We all know that benzene undergoes aromatic electrophilic substitution reactions. As a result the other electrophile gets attached to the benzene ring thereby forming Acetophenone (C6H5COCH3).

AlCl3 is also a catalyst in this reaction because it gives off its Cl minus after the end of reaction and HCl is formed as bye product.