Diethyl Acetamidomalonate: Properties, Synthesis & Lab Use

Diethyl acetamidomalonate is a versatile malonate-based building block widely employed in organic synthesis for the preparation of α-amino acids, pharmaceutically relevant intermediates, and structurally diverse nitrogen-containing compounds.

Chemical Name

Diethyl acetamidomalonate (diethyl 2-acetamido-2-malonate)

CAS Number

1068-90-2

Molecular Formula

C₉H₁₅NO₅

Molecular Weight

217.22 g/mol

Primary Application

Synthesis of α-amino acids and unnatural amino acid analogues via alkylation and hydrolysis/decarboxylation

Physical Form

Typically a white to off-white crystalline solid

SKU

D117538

Chemical Identity and Physical Properties

Diethyl acetamidomalonate (CAS 1068-90-2) is an ester derivative of malonic acid in which the central methine carbon bears an acetamido (NHCOCH₃) group. Its molecular formula is C₉H₁₅NO₅ with a molecular weight of approximately 217.22 g/mol. The compound typically appears as a white to off-white crystalline solid and is soluble in common polar organic solvents such as ethanol, dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), with limited solubility in water and non-polar solvents such as hexane.

The methine proton adjacent to the two electron-withdrawing ester groups and the acetamido group exhibits enhanced acidity, making the compound amenable to deprotonation under mild base conditions to generate a stabilized carbanion. This nucleophilic intermediate is central to the compound's synthetic utility.

Synthetic Applications and Reaction Chemistry

The primary application of diethyl acetamidomalonate in synthetic chemistry is as a glycine equivalent for the preparation of α-amino acids through the classical acetamidomalonate ester synthesis. The key steps are:

1. Deprotonation: Treatment with a base such as sodium ethoxide or potassium carbonate in an anhydrous polar aprotic solvent (e.g., DMF or ethanol) generates the reactive carbanion.
2. Alkylation: The carbanion reacts with an alkyl halide or other electrophile, introducing a side-chain at the α-carbon. A wide variety of electrophiles can be employed, enabling access to diverse amino acid side chains including those found in unnatural amino acids.
3. Hydrolysis and decarboxylation: Acid- or base-mediated hydrolysis of both ester groups followed by thermal decarboxylation of one carboxyl group yields the target α-amino acid, with removal of the acetyl protecting group completing the sequence.

This three-step strategy has been applied to the synthesis of natural α-amino acids (e.g., phenylalanine, alanine analogues) and a broad range of non-proteinogenic amino acids used in pharmaceutical research and peptide science.

Laboratory Handling, Storage, and Safety

Diethyl acetamidomalonate is generally considered a low-hazard reagent under standard laboratory conditions; however, standard precautions for handling fine chemicals should always be observed:

• Personal protective equipment (PPE): Wear appropriate lab coat, chemical-resistant gloves, and safety glasses. Avoid inhalation of dust.
• Storage: Store in a cool, dry, well-ventilated area, away from strong oxidising agents, strong bases, and moisture. Seal containers tightly after use to prevent moisture uptake and degradation. Refrigerated storage (2–8 °C) is recommended for long-term preservation of purity.
• Solvent selection: For reactions requiring deprotonation, use freshly dried solvents (anhydrous DMF, anhydrous ethanol) to maximise carbanion yield and minimise side reactions from moisture.
• Waste disposal: Dispose of waste in accordance with local institutional and regulatory guidelines for organic chemical waste.

Consult the Safety Data Sheet (SDS) provided with Aladdin Scientific product D117538 for complete hazard information, first-aid measures, and regulatory classifications before use.

Quality, Purity, and Analytical Characterisation

For reliable synthetic outcomes, the purity of diethyl acetamidomalonate is a critical parameter. Research-grade material should meet the following analytical benchmarks, and purchasers are advised to verify the certificate of analysis (CoA) upon receipt:

• Purity: ≥98% by gas chromatography (GC) or high-performance liquid chromatography (HPLC) is standard for research-grade supply.
• Melting point: Literature values for pure material are reported in the range of approximately 95–99 °C; deviation may indicate impurity or degradation.
• NMR characterisation: ¹H NMR (in CDCl₃) shows characteristic signals for the acetamido NH, the methine CH, the ester ethyl groups (quartet and triplet), and the acetyl methyl group. ¹³C NMR and IR spectroscopy further confirm structural identity.
• Appearance: Pure material is a white to off-white crystalline solid; yellowing or browning may indicate degradation.

Aladdin Scientific's product D117538 is supplied with lot-specific analytical data. Contact technical support for CoA requests or purity queries.

Ordering and Availability at Aladdin Scientific

Diethyl acetamidomalonate is available from Aladdin Scientific under SKU D117538. Researchers and procurement teams can place orders directly via the Aladdin Scientific online platform. The following points are relevant for purchasing decisions:

• Pack sizes: Multiple pack sizes may be available to suit small-scale research and larger batch requirements; consult the product page for current listing.
• Documentation: A certificate of analysis (CoA) and safety data sheet (SDS) are available for download on the product page or upon request from customer service.
• Lead time: Standard in-stock items ship promptly; confirm current stock status and lead times on the product listing page or by contacting the Aladdin Scientific sales team.
• Custom quantities: For bulk or custom requirements, contact Aladdin Scientific's procurement team directly.

For technical questions about application suitability, compatibility, or reaction optimisation, reach out to Aladdin Scientific's technical support team who can assist with reagent selection guidance.

Frequently asked questions

What is diethyl acetamidomalonate used for in organic synthesis?

Diethyl acetamidomalonate serves primarily as a glycine equivalent for the synthesis of α-amino acids, including both natural and unnatural amino acid analogues, via sequential alkylation, hydrolysis, and decarboxylation. It is also employed as a building block in the synthesis of pharmaceutical intermediates and nitrogen-containing heterocycles.

How should diethyl acetamidomalonate be stored to maintain its stability?

The compound should be stored in a tightly sealed container in a cool (ideally 2–8 °C), dry, and well-ventilated location, away from moisture, strong bases, and strong oxidising agents. Protecting the material from humidity is especially important, as moisture can promote ester hydrolysis and reduce purity over time.

What base and solvent are recommended for the alkylation of diethyl acetamidomalonate?

Sodium ethoxide in anhydrous ethanol or potassium carbonate in anhydrous DMF are the most commonly reported systems for deprotonation and subsequent alkylation of diethyl acetamidomalonate. The choice depends on the reactivity of the alkylating agent and the desired reaction temperature; potassium carbonate in DMF is often preferred for less reactive electrophiles due to the superior solvating power of DMF.

How can I confirm the purity of diethyl acetamidomalonate received from Aladdin Scientific?

Aladdin Scientific provides a lot-specific certificate of analysis (CoA) for product D117538, which documents purity (typically by GC or HPLC), melting point, and appearance. You can request the CoA through the product page or by contacting customer service. Additionally, purity can be verified in-house by GC, HPLC, or ¹H NMR spectroscopy.

Can diethyl acetamidomalonate be used to prepare unnatural amino acids for peptide research?

Yes, diethyl acetamidomalonate is widely used in peptide and medicinal chemistry research for the preparation of non-proteinogenic (unnatural) amino acids. By varying the alkyl halide or electrophile used in the alkylation step, researchers can introduce diverse side chains not found in the 20 canonical amino acids, enabling the synthesis of custom building blocks for structure-activity relationship (SAR) studies and peptide engineering.

References

1. March, J. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure. Wiley-Interscience. (Textbook-level reference for malonate ester synthesis and alkylation chemistry.)
2. Clayden, J.; Greeves, N.; Warren, S. Organic Chemistry. Oxford University Press. (Covers amino acid synthesis via malonate ester strategy.)
3. Aladdin Scientific. Product Certificate of Analysis: Diethyl acetamidomalonate, SKU D117538. Aladdin Scientific.

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.