Chemical Identity and Physical Properties

4-Amino-thiophene-2-carboxylic acid methyl ester (SKU: A187877) is an aromatic heterocyclic compound featuring a thiophene ring substituted at the 4-position with a primary amino group (–NH2) and at the 2-position with a methyl ester moiety (–COOCH3). Its molecular formula is C6H7NO2S with a molecular weight of approximately 157.19 g/mol.

The compound typically presents as a solid at room temperature. The primary amine renders the molecule moderately basic and nucleophilic, while the electron-withdrawing methyl ester group modulates the electron density of the thiophene ring. This combination of functional groups makes the compound highly reactive toward acylation, condensation, and cyclization reactions.

Note: Specific physical constants such as melting point, boiling point, and solubility data should be verified against the Certificate of Analysis (CoA) supplied with each lot. Contact Aladdin Scientific technical support for lot-specific data.

Synthetic Applications and Reactivity

4-Amino-thiophene-2-carboxylic acid methyl ester serves as a valuable bifunctional building block in organic and medicinal chemistry. Its dual functionality—the nucleophilic amino group and the electrophilic ester carbonyl—enables a broad spectrum of transformations:

• Acylation and Amide Bond Formation: The primary amine reacts readily with acyl chlorides, anhydrides, and activated esters to furnish amide derivatives. These products can serve as precursors to thienopyridinone or thienopyrimidinone scaffolds upon intramolecular cyclization.
• Condensation Reactions: The amino group undergoes condensation with aldehydes or ketones to form Schiff bases (imines), which are useful intermediates in further ring-closure chemistry.
• Ester Hydrolysis and Transesterification: The methyl ester can be selectively hydrolyzed to the corresponding carboxylic acid under basic or acidic conditions, or transesterified to access other ester analogs.
• Heterocycle Annulation: The 2,4-substitution pattern of this thiophene derivative is particularly suited to constructing fused bicyclic heterocycles, which are common scaffolds in drug discovery programs targeting kinases, ion channels, and other therapeutic targets.

Review flag: Specific reaction yields and conditions cited in literature should be independently verified; no specific literature references were available in the source material.

Handling, Safety, and Storage Guidelines

As with all fine chemical reagents, proper handling and storage of 4-Amino-thiophene-2-carboxylic acid methyl ester are essential to maintain product integrity and ensure laboratory safety.

Personal Protective Equipment (PPE)

• Wear appropriate chemical-resistant gloves (e.g., nitrile), laboratory coat, and safety goggles when handling this compound.
• Work in a well-ventilated area or under a fume hood to minimize inhalation exposure to dust or vapors.

Storage Conditions

• Store in a tightly sealed container in a cool, dry, and well-ventilated location, away from direct sunlight and incompatible materials such as strong oxidizers, strong acids, and strong bases.
• Specific recommended storage temperature should be confirmed from the product label and CoA. Refrigerated storage (2–8 °C) is commonly appropriate for aminothiophene compounds to prevent oxidation of the amine moiety.

Disposal

• Dispose of waste material in accordance with local, regional, and national regulations. Do not dispose of down the drain without proper treatment.

Review flag: A full Safety Data Sheet (SDS) for A187877 should be consulted for authoritative hazard classification, GHS pictograms, first-aid measures, and disposal codes. Refer to the Aladdin Scientific product page for the current SDS.

Quality, Purity, and Analytical Verification

Aladdin Scientific supplies 4-Amino-thiophene-2-carboxylic acid methyl ester (A187877) as a research-grade reagent. Researchers should verify purity and identity before use in sensitive synthetic or biological assays.

Recommended Analytical Techniques

• HPLC: Reverse-phase HPLC is the standard method for assessing chemical purity. A purity specification will be stated on the product CoA; researchers should request the CoA for each lot received.
• NMR Spectroscopy: 1H and 13C NMR in deuterated solvents (e.g., CDCl3 or DMSO-d6) confirm structural identity and detect major impurities. Key signals expected include aromatic/heteroaromatic protons, –NH2 broad signal, and –OCH3 singlet.
• Mass Spectrometry: ESI-MS or APCI-MS should yield an [M+H]+ ion consistent with the molecular weight of 157.19 g/mol (expected m/z ≈ 158.2 for [M+H]+).
• IR Spectroscopy: Characteristic absorptions include N–H stretches (~3300–3500 cm-1), C=O ester stretch (~1700 cm-1), and C=C/C=N thiophene ring vibrations.

Review flag: Exact purity specification and lot-specific analytical data are not available in the source material; users must consult the product CoA from Aladdin Scientific for confirmed values.