Identify the major product of the given reaction.

Step-by-step solution

The given reaction is an intramolecular Friedel-Crafts acylation. The acid chloride reacts with the Lewis acid catalyst AlCl ₃ to generate an electrophilic acylium ion. Ph - CH ₂- CH ₂- COCl + AlCl ₃ Ph - CH ₂- CH ₂- C ⁺= O + AlCl ₄⁻ The acylium ion acts as an electrophile and attacks the ortho position of the benzene ring. This intramolecular attack forms a new carbon-carbon bond, creating a 5-membered ring fused to the benzene ring. Loss of a proton from the intermediate sigma complex restores aromaticity, yieldi