Predict the product(s) and provide the mechanism for each reactionbelow. What does each mechanism have in common?

Freidal craft acylation reaction is the “substitution of electrophile (acylium ion)” on the electron-rich benzene ring. The electrophile is generated by reacting the acetyl/acyl chloride with lewis acid aluminum chloride $\left({\text{AlCl}}_{\text{3}}\right)$.

The formation of “acylium ion” is common in all friedal craft acylation reactions.

Reaction (a) is an intramolecular Friedel craft acylation reaction in which the acylium ion (electrophile) is generated within the reactant, which will attack the same reactant 3 - phenylpropanoyl chloride (nucleophile), leading to the formation 2,3-dihydro-1H-inden-1-one.

Formation of 2,3-dihydro-1H-inden-1-one

Reaction (b) is friedal craft acylation in which the acetyl chloride reacts with a lewis acid$\left({\text{AlCl}}_{\text{3}}\right)$ to form the acylium ion (electrophile), which attacks the reactant anisole (nucleophile), which is meta directing group, resulting in the attack of acylium group at the meta position, forming the product 1-(3-methoxyphenyl)ethenone.

Formation of 1-(3-methoxyphenyl)ethanone

Reaction (c) is friedal craft acylation in which propanoyl chloride reacts with a lewis acid$\left({\text{AlCl}}_{\text{3}}\right)$ to form the acylium ion (electrophile), which attacks the reactant tert-butylbenzene (nucleophile), which is ortho, para directing group, resulting in the attack of acylium group at the ortho and para position, forming the two products:

• Para product formed is 1-(4-tert-butylphenyl)propan-1-one
• Ortho product is 1-(2-tert-butylphenyl)propan-1-one

Formation of para and ortho product