Clemmensen reduction vs. Wolff-Kishner reduction?

Question

In which cases is the Clemmensen reduction is preferred over the Wolff-Kishner reduction? One thing is that the Clemmensen reduction is done under acidic conditions whereas the Wolff-Kishner reaction is done under basic condition, and that I think decides somewhat which to choose depending of the nature and other groups present in the reactant. But are there any other points to keep in mind while choosing the best suitable reaction?

Answer 1

I think you already explained it. To be safe, you should also understand what common functional groups might cause problems:

In acid, acetal/enamines/imines seem problematic. Tertiary alcohols and some alkenes could be an issue.

In base, alkyl halides could react via Sn2/E2.

I'm sure there are others. Mozingo reduction is often preferable also.