Chapter 21, Problem 21.68P

Interpretation Introduction

(a)

Interpretation:

The structures of missing products for the given reaction is to be drawn.

Concept introduction:

The alkylation of $\text{α}$ carbon of acetoacetic ester is relatively easy by removing a ${\text{CO}}_{\text{2}}\text{Et}$ group entirely from each of these compounds. The moderately strong base will remove an $\text{α}$ proton irreversibly which further followed by ${\text{S}}_{\text{N}}\text{2}$ reaction yields the alkylated $\text{α}$ carbon that is $\text{β-keto }$ ester. To remove the ester group $\left({\text{CO}}_{\text{2}}\text{Et}\right)$, heating is done under aqueous, acidic condition. Heating the $\text{β-keto }$ acid drives a decarboxylation in which gaseous ${\text{CO}}_{\text{2}}$ is lost and an enol is formed. The enol rapidly tautomerizes to the keto form.

Interpretation Introduction

(b)

Interpretation:

The structures of missing products for the given reaction is to be drawn.

Concept introduction:

The alkylation of $\text{α}$ carbon of acetoacetic ester is relatively easy by removing a ${\text{CO}}_{\text{2}}\text{Et}$ group entirely from each of these compounds. The moderately strong base will remove an $\text{α}$ proton irreversibly which further followed by ${\text{S}}_{\text{N}}\text{2}$ reaction yields the alkylated $\text{α}$ carbon that is $\text{β-keto }$ ester. To remove the ester group $\left({\text{CO}}_{\text{2}}\text{Et}\right)$, heating is done under aqueous, acidic condition. Heating the $\text{β-keto }$ acid drives a decarboxylation in which gaseous ${\text{CO}}_{\text{2}}$ is lost and an enol is formed. The enol rapidly tautomerizes to the keto form.