Question

Describe two ways to prepare each of the following compounds from benzene.

Short answer

The answer is,

a.

b.

Step-by-step solution

Friedel crafts alkylation

The Friedel crafts alkylation is the reaction of benzene with alkyl chloride in presence of Aluminium chloride. The alkyl group is substituted to the benzene ring by replacing the hydrogen atom.

Subpart (a)

The preparation methods of the given compound are shown below.

The Freidel crafts alkylation reaction of benzene with 2-chloropentane and aluminium chloride to give the desired product.

And

In this method, the reagent is 1-chloropentane. The alkyl cation formed here undergoes rearrangement to give the stable cation to form the desired product.

Subpart (b)

The preparation methods of the given compound are shown below.

The benzene when reacts with acyl chloride followed by the reduction reaction yields the desired product.

The benzene undergoes bromination in presence of ferric bromide to give bromobenzene, which reacts with organocuprate to give the desired product.