Clemmensen Reduction: Carbonyl → Methylene (Acidic Conditions)

Learn the Clemmensen reduction: reducing aldehydes/ketones to alkanes under strongly acidic conditions. When to choose Clemmensen vs Wolff–Kishner.

• Reaction: Aldehyde/ketone → alkane
• What it does: Deletes the carbonyl oxygen (C=O → CH2)
• Typical reagents: Zn(Hg), HCl (acidic)
• Key intermediate: Surface/metal-mediated (not usually arrow-pushed in full detail in Orgo)
• Driving force: Net reduction; formation of C–H bonds
• Exam type: Reagent selection
• Exam type: Transformations