Chapter 18, Problem 18.99P

Interpretation Introduction

(a)

Interpretation:

The structure of the product is to be determined from the given information.

Concept introduction:

Compare the molecular formula of the given reactants to the products to find out the type of the reaction and structure of the product.

From the given NMR data, the structure of the product can be determined.

Interpretation Introduction

(b)

Interpretation:

Complete and detailed mechanism for the given reaction is to be drawn.

Concept introduction:

In aldol reaction, joining of two reactants takes place.

The only acidic $\text{C-H}$ atom in $\text{but-2-enal}$ is present on C4 carbon atom, which is attached to the carbonyl carbon of the $\text{3-phenylpropenal}$, resulting in the formation of an aldol product.

In heterolysis, water is removed, and alkene is formed.