What Is 2-Bromo-4-chloro-5-methylpyridine?

2-Bromo-4-chloro-5-methylpyridine is a halogenated pyridine derivative carrying a bromine substituent at the 2-position, a chlorine substituent at the 4-position, and a methyl group at the 5-position of the pyridine ring. This combination of substituents makes the molecule an attractive multi-functional building block in synthetic organic chemistry.

The presence of two different halogen atoms (Br and Cl) on the aromatic ring allows chemists to exploit their differential reactivity. The C–Br bond is typically more reactive toward palladium-catalyzed cross-coupling reactions (such as Suzuki, Miyaura, Negishi, and Buchwald–Hartwig couplings), while the C–Cl bond can be engaged selectively under more forcing conditions or in nucleophilic aromatic substitution reactions. This chemoselectivity is a key reason the compound is widely adopted in fragment-based drug discovery and lead optimization programs.

Common Laboratory Applications

Research scientists use 2-Bromo-4-chloro-5-methylpyridine primarily as an electrophilic coupling partner or intermediate in multi-step synthesis. Typical applications include:

• Palladium-catalyzed cross-coupling: The C–Br bond undergoes efficient Suzuki–Miyaura coupling with aryl- and heteroarylboronic acids, and Negishi coupling with organozinc reagents, enabling rapid construction of biaryl and heteroaryl frameworks common in drug candidates.
• Nucleophilic aromatic substitution (SNAr): The electron-deficient pyridine ring activated by both halogens facilitates SNAr with amines, alkoxides, and thiols, particularly at the C–Cl position under appropriate conditions.
• Buchwald–Hartwig amination: Selective C–N bond formation at the C–Br position is achievable with appropriate palladium/ligand systems.
• Agrochemical intermediate synthesis: Halopyridines are key scaffolds in the design of herbicides, fungicides, and insecticides.

Researchers should plan reaction sequences carefully to exploit the differential reactivity of the two halogen sites and minimize unwanted side reactions.

Storage, Handling, and Safety Guidelines

Proper storage and handling of 2-Bromo-4-chloro-5-methylpyridine are essential to maintain compound integrity and ensure laboratory safety. The following general guidelines apply to halogenated pyridine reagents of this class:

• Storage: Store in a cool, dry, well-ventilated area, away from heat sources and incompatible materials such as strong oxidizers and strong bases. A temperature range of 2–8 °C or room temperature storage under inert atmosphere may be recommended — consult the product Certificate of Analysis (CoA) for specific conditions.
• Container: Keep the container tightly sealed when not in use to prevent moisture ingress and atmospheric oxidation.
• Personal Protective Equipment (PPE): Use appropriate PPE including chemical-resistant gloves, lab coat, and safety goggles when handling this compound. Work in a fume hood to minimize inhalation exposure.
• Disposal: Dispose of waste in accordance with local regulations for halogenated organic compounds.

Always consult the current Safety Data Sheet (SDS) provided by Aladdin Scientific before working with this compound.

Ordering and Specifications

2-Bromo-4-chloro-5-methylpyridine is available from Aladdin Scientific under SKU B734557. When placing an order or evaluating the product for your research, consider the following:

• Purity: Confirm the purity specification on the product page or Certificate of Analysis (CoA) before use in sensitive synthetic steps. Typical purity for research-grade halopyridines is ≥95% (GC or HPLC); verify with the current CoA.
• Pack sizes: Multiple pack sizes may be available to suit screening-scale through gram-scale synthesis needs. Contact Aladdin Scientific for custom quantities if required.
• Documentation: CoA, SDS, and NMR/MS spectral data may be available upon request to support quality verification workflows.
• Lead time: Check current stock status on the Aladdin Scientific website or contact customer service for availability and estimated delivery timelines.