Chapter 19, Problem 19.44P

Interpretation Introduction

(a)

Interpretation:

The product of the given reaction is to be predicted.

Concept introduction:

The carbonyl groups of aldehyde or ketone can be reduced to methylene i.e. $\text{C=O}$ to ${\text{CH}}_{\text{2}}$ using the reactions like Wolff-Kishner reduction, Clemmensen reduction, and Raney-nickel reduction. Clemmensen reduction uses a zinc amalgam, which is an alloy (blend) of zinc with mercury. The ketone or aldehyde is refluxed (i.e., continuously evaporated and recondensed under heat) with the amalgam in concentrated HCl solution.

Interpretation Introduction

(b)

Interpretation:

The product of the given reaction is to be predicted

Concept introduction:

The carbonyl groups of aldehyde or ketone can be reduced to methylene i.e. $\text{C=O}$ to ${\text{CH}}_{\text{2}}$ using the reactions like Wolff-Kishner reduction, Clemmensen reduction, and Raney-nickel reduction. The reagent used for Wolff-Kishner reduction is ${\text{NH}}_{\text{2}}{\text{NH}}_{\text{2}}{\text{, NaOH, H}}_{\text{2}}\text{O,}\Delta$.

Interpretation Introduction

(c)

Interpretation: The product of the given reaction is to be predicted

Concept introduction:

The carbonyl groups of aldehyde or ketone can be reduced to methylene i.e. $\text{C=O}$ to ${\text{CH}}_{\text{2}}$ using reactions like Wolff-Kishner reduction, Clemmensen reduction, and Raney-nickel reduction. In a Raney-nickel reduction, the ketone or aldehyde is first converted to a thioacetal by treatment with a thiol under acidic conditions. Subsequent treatment with Raney nickel converts the thioacetal group to a methylene group.