Chapter 21, Problem 21.89P

Interpretation Introduction

(a)

Interpretation:

How the given synthesis can be carried out is to be suggested.

Concept introduction:

$\text{β}$-Keto esters can be synthesized in a reaction known as Claisen condensation. The $\text{α}$-hydrogen in an carbonyl compound is relatively acidic because of the presence of an adjacent electron withdrawing group. A strong bulky, non-nuclophilic base extracts this proton, resulting in the formation of a carbon nucleophile. The nucleophile attacks and adds to the electrophilic carbon of a carbonyl compound such as an ester to form a tetrahedral intermediate. The elimination of the original alkoxide (acyl) group from this intermediate followed by proton transfers completes the reaction, giving an $\text{α}$-keto ester.

Interpretation Introduction

(a)

Interpretation:

How the given synthesis can be carried out is to be suggested.

Concept introduction:

$\text{β}$-Keto esters can be synthesized in a reaction known as Claisen condensation. The $\text{α}$-hydrogen in an carbonyl compound is relatively acidic because of the presence of an adjacent electron withdrawing group. A strong bulky, non-nuclophilic base extracts this proton, resulting in the formation of a carbon nucleophile. The nucleophile attacks and adds to the electrophilic carbon of a carbonyl compound such as an ester to form a tetrahedral intermediate. The elimination of the original alkoxide (acyl) group from this intermediate followed by proton transfers completes the reaction, giving an $\text{α}$-keto ester.