Chapter 17, Problem 17.41P

Interpretation Introduction

(a)

Interpretation:

The mechanism for the given reaction is to be drawn. The major product mechanism is to be predicted.

Concept introduction:

Sodium borohydride ${\text{NaBH}}_{\text{4}}$, is a reducing reagent and the key electron-rich species in it is a hydride ion (${\text{H}}^{\text{-}}$). The reactant is a cyclic ketone that has an electron-deficient carbonyl carbon. ${\text{NaBH}}_{\text{4}}$ is capable of reducing polar $\text{π}$ bonds such as that in a carbonyl group, particularly in aldehydes and ketones. The reaction involves the nucleophilic addition of the hydride ion to the carbonyl carbon, followed by a proton transfer from the solvent. The result is the reduction of an aldehyde or a ketone to alcohol.

Interpretation Introduction

(b)

Interpretation:

The mechanism for the given reaction is to be drawn. The major product mechanism is to be predicted.

Concept introduction:

Sodium borohydride ${\text{NaBH}}_{\text{4}}$, is a reducing reagent and the key electron-rich species in it is a hydride ion (${\text{H}}^{\text{-}}$). The reactant is a cyclic ketone that has an electron-deficient carbonyl carbon. ${\text{NaBH}}_{\text{4}}$ is capable of reducing polar $\text{π}$ bonds such as that in a carbonyl group, particularly in aldehydes and ketones. The reaction involves the nucleophilic addition of the hydride ion to the carbonyl carbon, followed by a proton transfer from the solvent. The result is the reduction of an aldehyde or a ketone to alcohol.

Interpretation Introduction

(c)

Interpretation:

Concept introduction:

Lithium aluminum hydride ${\text{LiAlH}}_{\text{4}}$, is a reducing reagent and the key electron-rich species in it is a hydride ion (${\text{H}}^{\text{-}}$). The reactant is a cyclic ketone that has an electron-deficient carbonyl carbon. ${\text{LiAlH}}_{\text{4}}$ is capable of reducing polar $\text{π}$ bonds such as those in a carbonyl group, particularly in aldehydes and ketones. The reaction involves the nucleophilic addition of the hydride ion to the carbonyl carbon, followed by a proton transfer from the solvent. The result is the reduction of an aldehyde or a ketone to alcohol.