Chapter 25, Problem 57PP

Interpretation Introduction

Interpretation:

Why there is a difference in yield when alanine and valine is prepared via amidomalonate synthesis need to be explained.

Concept introduction:

Amidomalonate synthesis is a process in which a halide is converted to a aminoacid with two new carbon atoms (comes from amidomalonate).  By use of this method a new alkyl groups can be introduced.  A general scheme of this synthesis is shown below,

Steps involved in amidomalonater synthesis are,

• Deprotonation of $\alpha$ carbon in amidomalonate
• Alkylation of enolate
• Hydrolysis of ester using aqueous acid
• Decarboxylation at high temperature

Please remember that if the primary alkyl halide reactivity is more than secondary alkyl halide due to less steric hindrance.