2-Amino-5-iodopyridine
[CAS# 20511-12-0]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Pyridine compound >> Iodopyridine
• Name: 2-Amino-5-iodopyridine
• Synonyms: 5-iodopyridin-2-amine
• Molecular Formula: C₅H₅IN₂
• Molecular Weight: 220.01
• CAS Registry Number: 20511-12-0
• EC Number: 626-319-0
• SMILES: C1=CC(=NC=C1I)N

Properties

• Melting point: 127-131 °C
• Water solubility: Insoluble

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H302-H312-H315-H319-H332-H335
• Safety Statements: P261-P264-P264+P265-P270-P271-P280-P301+P317-P302+P352-P304+P340-P305+P351+P338-P317-P319-P321-P330-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2	H319
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H332
Eye irritation	Eye Irrit.	2A	H319

Discovery and Applications

2-Amino-5-iodopyridine is a versatile chemical compound that has garnered attention for its significant role in organic synthesis, particularly in the development of pharmaceuticals and other biologically active molecules. This compound, characterized by an amino group at the 2-position and an iodine atom at the 5-position of the pyridine ring, was first synthesized as part of efforts to explore the reactivity and synthetic utility of halogenated pyridines.

The discovery of 2-amino-5-iodopyridine is rooted in the broader study of halopyridines, which are known for their ability to participate in a variety of chemical reactions due to the presence of both nucleophilic and electrophilic sites on the pyridine ring. The introduction of an iodine atom at the 5-position increases the compound's reactivity, particularly in cross-coupling reactions, making it a valuable intermediate in the synthesis of more complex molecules. The amino group at the 2-position further enhances the compound's versatility, allowing it to engage in additional functionalization reactions, which is critical for the development of a wide range of chemical products.

One of the primary applications of 2-amino-5-iodopyridine is in the pharmaceutical industry, where it serves as a key intermediate in the synthesis of various drug candidates. The compound's structure makes it particularly useful in the construction of heterocyclic frameworks that are common in many biologically active compounds. For example, 2-amino-5-iodopyridine is often used in the synthesis of kinase inhibitors, which are a class of drugs that target enzymes involved in the regulation of cellular processes such as growth and division. These inhibitors have shown promise in the treatment of cancer and other diseases, making 2-amino-5-iodopyridine a valuable component in drug discovery.

In addition to its role in drug synthesis, 2-amino-5-iodopyridine is also utilized in the creation of advanced materials. The compound's ability to undergo cross-coupling reactions, such as Suzuki or Sonogashira couplings, allows it to be incorporated into polymers and other materials with desirable electronic and optical properties. These materials have potential applications in the development of organic electronic devices, such as organic light-emitting diodes (OLEDs) and organic photovoltaics (OPVs). The iodine atom in 2-amino-5-iodopyridine facilitates the formation of carbon-carbon bonds, enabling the construction of complex molecular architectures that are essential for the performance of these devices.

The versatility of 2-amino-5-iodopyridine extends to its use in the synthesis of dyes and pigments. The compound's reactivity allows it to be functionalized with a variety of chromophores, resulting in dyes with unique colors and properties. These dyes can be used in textiles, inks, and other applications where color stability and intensity are important. The presence of the iodine atom also enables the introduction of additional functional groups that can modify the solubility, brightness, and other characteristics of the dyes, making 2-amino-5-iodopyridine a key building block in the design of advanced coloring agents.

Moreover, 2-amino-5-iodopyridine is valuable in the field of medicinal chemistry beyond drug synthesis. Its ability to act as a precursor in the synthesis of ligands for metal complexes makes it useful in the development of imaging agents and diagnostic tools. These metal complexes can be designed to target specific biological sites, allowing for the visualization of disease states using techniques such as magnetic resonance imaging (MRI) or positron emission tomography (PET). The ability to fine-tune the properties of these complexes by modifying the 2-amino-5-iodopyridine precursor contributes to the advancement of non-invasive diagnostic methods.

Research into 2-amino-5-iodopyridine continues to explore new applications and synthetic methodologies that leverage its unique structural features. The compound's combination of reactivity, versatility, and ease of functionalization ensures its ongoing importance in both industrial and academic settings. As new challenges and opportunities arise in the fields of drug discovery, materials science, and chemical synthesis, 2-amino-5-iodopyridine is likely to remain a crucial tool for researchers and chemists.

References

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DOI: 10.1126/science.abo7201

2016. Recent Advances in Transition-Metal-Catalyzed Iodination of Arenes. Synthesis, 48(20).
DOI: 10.1055/s-0035-1562439

2007. Vibrational spectra and assignments of 2-amino-5-iodopyridine by ab initio Hartree-Fock and density functional methods. Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 67(3-4).
DOI: 10.1016/j.saa.2006.08.040