Question

The enolate derived from diethyl acetamidomalonate is treated with each of the following alkyl halides. After hydrolysis and decarboxylation, what amino acid is formed?

$$\begin{gathered} \left(a\right)C{H}_3\mathrm{I} \\ \left(b\right){\left({\mathrm{CH}}_3\right)}_2{\mathrm{CHCH}}_2\mathrm{Cl} \\ \left(c\right){\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CH}\left({\mathrm{CH}}_3\right)\mathrm{Br} \end{gathered}$$

Short answer

(a)

(b)

(c)

Step-by-step solution

Amino acid

Amino acids are composed of three components: carboxyl group,group, and side chains.Carboxyl groups are deprotonated at physiological pH and group is protonated at physiological pH. Amino acid cartels to form proteins.

Reagents

${\mathrm{CH}}_3\mathrm{I}$, ${\left({\mathrm{CH}}_3\right)}_2{\mathrm{CHCH}}_2\mathrm{Cl}$and${\mathrm{CH}}_3{\mathrm{CH}}_2\mathrm{CH}\left({\mathrm{CH}}_3\right)\mathrm{Br}$ and are alkyl halides that act as methylating agents for substitution or addition of methyl group in a reaction and are also used as solvents.

Reaction

(a) When diethyl acetamidomalonate is treated, a compound is formed, which on hydrolysis we get alanine

Formation of alanine

(b) When diethyl acetamidomalonate is treated, a compound is formed, which on hydrolysis we get leucine.

Formation of leucine

(c) When diethyl acetamidomalonate is treated, a compound is formed, which on hydrolysis we get isoleucine.

Formation of isoleucine