Chapter 22.9, Problem 22.29P

(a)

Interpretation Introduction

Interpretation:

The synthesis of Cinnamaldehyde by a crossed aldol condensation followed by dehydration is to be proposed.

Concept introduction:

The reaction between the enolate of one aldehyde or ketone and the carbonyl group of a different aldehyde or ketone is known as crossed aldol condensation reaction. The reaction takes place only when one of the reactant has an alpha hydrogen atom.

(b)

Interpretation Introduction

Interpretation:

The complete reaction in each given case is to be stated and an explanation for the observation of different results is to be explained.

Concept introduction:

LDA (Lithium Di-isopropyl Amide) is a strong base with a molecular formula, ${\left[{\left({\text{CH}}_{\text{3}}\right)}_{\text{2}}\text{CH}\right]}_{\text{2}}\text{NLi}$. It is most commonly used in the formation of enolates. Enolate acts as a useful nucleophile that participates in ${\text{S}}_{\text{N}}\text{2}$ reaction as well as aldol reaction.