Chemistry Aldehydes & Ketones DUHS 2024
PMDC Verified Question 6 of 94
Reduction of aldehydes & ketones by \( Zn-Hg \) amalgam and concentrated \( HCl \) results in conversion to an alkane. This reaction is known as:
A
Down Reduction
B
Wolf-Kishner Reduction
C
Cope Reduction
D
Clemmensen Reduction
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: Clemmensen Reduction
Concept:

Specific deoxygenation reactions are named after the chemists who discovered the reagent combinations required to strip oxygen completely from a carbonyl group.

Solution:

  • The transformation of a carbonyl (\( C=O \)) directly into a methylene (\( CH_2 \)) group requires aggressive reduction.


  • The specific use of Zinc amalgam (\( Zn-Hg \)) in concentrated Hydrochloric acid (\( HCl \)) provides a highly acidic reducing environment.


  • This specific reagent set is named the Clemmensen Reduction. It is highly effective for ketones that are stable in strong acids.


Why other options are incorrect:

The Wolff-Kishner reduction achieves the same result but uses strongly basic conditions (Hydrazine and \( KOH \)). Cope reduction does not exist in this standard context. Down reduction is a fabricated term.

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