2,6-Dibromopyridine
[CAS# 626-05-1]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Pyridine compound >> Bromopyridine
• Name: 2,6-Dibromopyridine
• Molecular Formula: C₅H₃Br₂N
• Molecular Weight: 236.89
• CAS Registry Number: 626-05-1
• EC Number: 210-926-9
• SMILES: C1=CC(=NC(=C1)Br)Br

Properties

• Density: 2.1±0.1 g/cm³, Calc.^*
• Melting point: 117-119 °C (Expl.)
• Index of Refraction: 1.607, Calc.^*
• Boiling Point: 255.9±20.0 °C (760 mmHg), Calc.^*, 255 °C (Expl.)
• Flash Point: 108.5±21.8 °C, Calc.^*, 213 °C (Expl.)
• Water solubility: insoluble (Expl.)

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS06;GHS07 Danger
• Risk Statements: H300-H315-H319-H332-H335-H412
• Safety Statements: P261-P264-P264+P265-P270-P271-P273-P280-P301+P316-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.	2	H300
Acute toxicity	Acute Tox.	1	H300
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Eye irritation	Eye Irrit.	2A	H319
Acute toxicity	Acute Tox.	4	H332
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H302

• Transport Information: UN 2811

Discovery and Applications

2,6-Dibromopyridine is a chemical substance that has gained attention for its versatile applications in various fields, particularly in the synthesis of pharmaceutical compounds and as an intermediate in organic chemistry. It is part of the class of halogenated pyridines, which are well-known for their reactivity and ability to participate in a wide range of chemical reactions, including cross-coupling reactions and nucleophilic substitution.

The discovery of 2,6-dibromopyridine can be traced back to the development of halogenated pyridine derivatives, which became significant in the mid-20th century. The introduction of halogens such as bromine into the pyridine ring structure was aimed at improving the compound's reactivity and stability, making it useful for a wide range of synthetic processes. The halogenation of pyridine rings at specific positions allows for selective reactions that are beneficial in the synthesis of more complex molecules. 2,6-Dibromopyridine, in particular, offers a useful scaffold for further chemical modifications, leading to the development of various bioactive compounds.

One of the primary applications of 2,6-dibromopyridine is as an intermediate in the synthesis of pharmaceutical compounds. Its ability to undergo cross-coupling reactions, such as Suzuki-Miyaura and Heck reactions, makes it valuable in the creation of complex organic molecules. These reactions are often used in the synthesis of heterocyclic compounds, which are critical for developing drugs with specific biological activities. For instance, 2,6-dibromopyridine can be used to form bipyridine-based ligands for metal complexes, which are utilized in catalysis and drug development.

In addition to its role in pharmaceutical synthesis, 2,6-dibromopyridine is also employed in the agrochemical industry. It serves as a precursor in the development of herbicides and pesticides, as the functional groups on the pyridine ring can be further modified to create molecules with specific activity against pests or undesirable plants. The versatility of 2,6-dibromopyridine in various synthetic routes has made it a crucial building block in the production of a range of agrochemical products.

2,6-Dibromopyridine also finds applications in materials science, where it is used as a component in the development of organic electronic materials. Its ability to form stable bonds with metals and other organic molecules makes it a useful candidate for the production of organic semiconductors and conductive materials used in electronic devices, such as organic light-emitting diodes (OLEDs) and organic solar cells.

Despite its usefulness, the handling of 2,6-dibromopyridine requires caution due to the toxicity of the bromine atoms, which can pose environmental and health risks. Proper safety measures should be followed in its synthesis and application to minimize exposure and potential harm. However, the demand for 2,6-dibromopyridine in synthetic chemistry and industry continues to grow, driven by its utility as a building block for complex molecules and materials.

In conclusion, 2,6-dibromopyridine is an important chemical compound with wide-ranging applications in the pharmaceutical, agrochemical, and materials science industries. Its role as an intermediate in chemical synthesis, coupled with its reactivity in cross-coupling reactions, makes it a valuable tool for the development of a variety of bioactive and functional materials. As research continues into its potential uses, 2,6-dibromopyridine is likely to remain a key compound in both academic and industrial chemical synthesis.

References

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DOI: 18139339

2015. A Facile Route to Substituted Bidentate and Tridentate Ligands Capable of Forming Six-membered Chelate Rings with Transition-Metal Ions. Synlett.
DOI: 10.1055/s-0034-1380654

2016. Sequential and iterative Pd-catalyzed cross-coupling reactions in organic synthesis. Monatshefte für Chemie - Chemical Monthly.
DOI: PMC5225241