Chapter 13, Problem 47P

Interpretation Introduction

Interpretation:

The major product of the reaction of $\text{o-bromotoluene}$ with acetyl chloride and aluminum chloride is to be predicted.

Concept introduction:

Fridel-Crafts acylation is a type of electrophilic aromatic substitution reaction in which an acyl group is the electrophile and replaces the hydrogen atom on the aromatic ring.

Partial rate factor is the experimentally determined relative data for rates of electrophilic aromatic substitution reactions.

Substituents which pull the electron density away from carbon atom are the electron withdrawing substituents.

Substituents which donate the electron density to the carbon atom are the electron releasing substituents.

Electron withdrawing substituents deactivate the ring and direct the upcoming electrophile to meta positions.

Electron releasing substituents activate the ring and direct the upcoming electrophile to ortho-para positions.

Halogen substituents are strongly deactivating but are ortho-para directing.

If aromatic ring having two substituents, the regioselectivity of electrophilic aromatic substitution is controlled by the more activating substituent.