What amino acid is formed using the N-phthalimidomalonic ester synthesis when the following alkyl halides are used in the third step?
a.

Verified step by step guidance

1. Step 1: Understand the N-phthalimidomalonic ester synthesis. This is a method used to synthesize α-amino acids. The process involves three main steps: (1) deprotonation of the malonic ester derivative, (2) alkylation with an alkyl halide, and (3) hydrolysis and decarboxylation to yield the amino acid.
2. Step 2: Analyze the given alkyl halide, (CH3)2CHCH2Br. This is an isobutyl bromide, which contains a four-carbon chain with a branching methyl group at the second carbon.
3. Step 3: In the alkylation step, the deprotonated N-phthalimidomalonic ester acts as a nucleophile and attacks the electrophilic carbon in the alkyl halide, replacing the bromine atom. This results in the formation of a substituted malonic ester with the isobutyl group attached to the α-carbon.
4. Step 4: In the final step, hydrolysis of the ester groups and decarboxylation occur. This removes the phthalimide protecting group and one of the carboxylic acid groups, leaving behind an α-amino acid with the isobutyl side chain.
5. Step 5: Recognize that the amino acid formed has the structure of leucine, which is an α-amino acid with an isobutyl side chain. This is the final product of the synthesis.

Key Concepts

N-phthalimidomalonic ester synthesis

N-phthalimidomalonic ester synthesis is a method for synthesizing amino acids, particularly α-amino acids. This reaction involves the use of phthalimide and malonic ester, where the phthalimide acts as a protective group for the amine. The process includes the alkylation of the malonic ester followed by hydrolysis and decarboxylation, ultimately yielding the desired amino acid.

Alkyl halides

Alkyl halides are organic compounds containing a carbon atom bonded to a halogen atom (such as bromine, chlorine, or iodine). In the context of the N-phthalimidomalonic ester synthesis, alkyl halides serve as the electrophilic species that react with the nucleophilic malonic ester. The choice of alkyl halide influences the structure of the resulting amino acid, as it determines the side chain attached to the α-carbon.

Decarboxylation

Decarboxylation is a chemical reaction that involves the removal of a carboxyl group (-COOH) from a molecule, releasing carbon dioxide (CO2). In the synthesis of amino acids via N-phthalimidomalonic ester synthesis, decarboxylation occurs after hydrolysis, leading to the formation of the final amino acid product. This step is crucial as it helps in achieving the correct structure and functionality of the amino acid.