Chapter 19.SE, Problem 76AP

Interpretation Introduction

a)

Interpretation:

The flaw in the reaction scheme given is to be identified and the corrected scheme is to be provided.

Concept introduction:

α,β-Unsaturated ketones when treated with Grignard reagents yield a product with the 1,2-addition of RH to the C = O bond in the ketone to yield a tertiary alcohol. The C = O group in ketones is reduced to a secondary alcohol by LiAlH₄.

To identify:

The flaw in the reaction scheme given and to provide the corrected scheme.

Interpretation Introduction

b)

Interpretation:

The flaw in the reaction scheme given is to be identified and corrected scheme is to be given.

Concept introduction:

CrO₃ in the presence of H₃O⁺ oxidize primary alcohols to acids and not to aldehydes. Aldehyde can be converted into an acetal by treating with methanol in the presence of acids.

To identify:

The flaw in the reaction scheme given and to provide the corrected scheme.

Interpretation Introduction

c)

Interpretation:

The flaw in the reaction scheme given is to be identified and corrected scheme is to be given.

Concept introduction:

Aldehydes and ketones react with HCN, KCN to yield the corresponding cyanohydrins. The cyanohydrins when treated with aqueous acids will get hydrolysed to acids.

To identify:

The flaw in the reaction scheme given and to provide the corrected scheme.