Clemmensen Reduction

Professor Dave explains Clemmensen Reduction, a reaction that converts ketones to alkanes using amalgamated zinc in hydrochloric acid. The mechanism is disputed, with two main hypotheses. A key application is in Friedel-Crafts chemistry, where Clemmensen Reduction helps achieve straight-chain alkyl groups on benzene rings. The process involves a two-step sequence: Friedel-Crafts acylation followed by Clemmensen Reduction. This method avoids carbocation rearrangement issues seen in alkylation.

Explain why Friedel-Crafts alkylation may not work as intended when trying to attach a straight-chain alkyl group to a benzene ring.

What is the two-step process to achieve the desired alkyl group on a benzene ring using Clemmensen reduction?