5-Bromo-2-cyclopropylpyrimidine: Properties, Uses & Handling

5-Bromo-2-cyclopropylpyrimidine is a halogenated heterocyclic building block featuring a cyclopropyl substituent at the 2-position of the pyrimidine ring and a bromine atom at the 5-position, making it a versatile intermediate for medicinal chemistry and cross-coupling reactions.

CAS Number

1211517-71-3

Molecular Formula

C7H7BrN2

Molecular Weight

199.05 g/mol

Aladdin SKU

B635874

Key Functional Groups

Aryl bromide, pyrimidine ring, cyclopropyl group

Primary Application

Suzuki–Miyaura and other transition-metal-catalyzed cross-coupling reactions; pharmaceutical intermediate synthesis

Chemical Identity and Structure

5-Bromo-2-cyclopropylpyrimidine (Aladdin SKU B635874) is a six-membered nitrogen-containing heterocycle belonging to the pyrimidine family. The pyrimidine core carries a cyclopropyl group at the 2-position and a bromine substituent at the 5-position. This combination imparts distinct electronic and steric characteristics: the electron-withdrawing pyrimidine ring activates the C–Br bond toward oxidative addition, while the cyclopropyl group at C-2 provides conformational rigidity, lipophilicity modulation, and a bioisosteric alternative to methyl or tert-butyl groups frequently exploited in drug discovery.

The molecular formula is C₇H₇BrN₂ with a molecular weight of approximately 199.05 g/mol. The compound is typically obtained as a white to off-white crystalline solid or powder.

Synthetic Utility and Applications

The aryl bromide functionality in 5-Bromo-2-cyclopropylpyrimidine makes it an excellent electrophilic partner in a wide range of transition-metal-catalyzed transformations:

• Suzuki–Miyaura coupling: Reaction with aryl- or heteroarylboronic acids under palladium catalysis to introduce diverse (hetero)aryl groups at C-5 of the pyrimidine ring.
• Buchwald–Hartwig amination: Palladium-catalyzed C–N bond formation with primary or secondary amines, providing access to 5-amino-2-cyclopropylpyrimidine derivatives relevant to kinase-inhibitor scaffolds.
• Negishi and Kumada couplings: Compatible with organozinc and organomagnesium reagents for alkyl or aryl introduction.
• Directed metalation and lithiation: The C–Br bond can be engaged in halogen–metal exchange with n-BuLi at low temperature to generate a pyrimidyl lithium species for further functionalization.

In medicinal chemistry, the cyclopropyl-pyrimidine pharmacophore is found in bioactive scaffolds targeting protein kinases, receptor tyrosine kinases, and other enzymes. The cyclopropyl group can improve metabolic stability and binding affinity compared to simple alkyl substituents.

Storage, Handling, and Stability

To maintain the integrity of 5-Bromo-2-cyclopropylpyrimidine, observe the following best practices:

• Storage temperature: Store in a cool, dry place, typically at 2–8 °C or room temperature under inert atmosphere when opened, as recommended on the product label. Confirm exact conditions from the Certificate of Analysis (CoA).
• Container: Keep the container tightly sealed under an inert gas (nitrogen or argon) to prevent moisture uptake and oxidation of the aryl bromide.
• Light sensitivity: Protect from prolonged exposure to light as a precautionary measure.
• Stability: Aryl bromides are generally stable under recommended storage conditions; however, repeated freeze-thaw cycles should be minimized.
• Handling: Use appropriate PPE including nitrile gloves, safety glasses, and lab coat. Work in a well-ventilated fume hood. Avoid inhalation of dust or aerosols.

Always consult the Safety Data Sheet (SDS) provided by Aladdin Scientific before use, as it contains the most up-to-date hazard, first-aid, and disposal information.

Quality, Purity, and Specification Guidance

Aladdin Scientific supplies 5-Bromo-2-cyclopropylpyrimidine (SKU B635874) with purity specifications verified by analytical methods such as GC or HPLC. Researchers should review the Certificate of Analysis (CoA) accompanying each lot for:

• Purity (%) by GC or HPLC
• ¹H NMR confirmation of structure
• Appearance (color, physical form)
• Lot-specific moisture content where applicable

For sensitive applications—such as cross-coupling reactions where catalyst poisoning by impurities is a concern—additional in-house characterization (e.g., ICP-MS for trace metal content) may be warranted. Contact Aladdin Scientific technical support for custom purity grades or bulk quantities.

Frequently asked questions

What transition-metal-catalyzed reactions is 5-Bromo-2-cyclopropylpyrimidine commonly used in?

It is most frequently employed in Suzuki–Miyaura cross-coupling with boronic acids, Buchwald–Hartwig C–N amination, and Negishi or Kumada couplings with organometallic reagents. The activated C–Br bond on the electron-deficient pyrimidine ring facilitates oxidative addition to palladium(0) catalysts.

How should I store 5-Bromo-2-cyclopropylpyrimidine to ensure long-term stability?

Store the compound in a tightly sealed container under an inert atmosphere (nitrogen or argon) in a cool, dry location away from light and moisture. Always verify the exact recommended storage conditions on the product label and Certificate of Analysis supplied with your lot.

Why is the cyclopropyl group at the 2-position of pyrimidine valuable in drug discovery?

The cyclopropyl group acts as a conformationally restricted, metabolically stable bioisostere of larger alkyl groups. It can improve binding affinity to biological targets by reducing conformational entropy and may enhance metabolic stability by resisting cytochrome P450-mediated oxidation compared to open-chain alkyl substituents.

What purity grade is available for SKU B635874, and how is it verified?

Aladdin Scientific verifies purity by GC or HPLC analysis, with structural confirmation by NMR. Specific purity values and analytical data are provided in the Certificate of Analysis (CoA) included with each shipment. Contact Aladdin Scientific for lot-specific CoA documentation or custom purity requirements.

References

1. General reference on pyrimidine chemistry and cross-coupling reactions — see leading organometallic chemistry textbooks (e.g., Clayden, Greeves, Warren, Organic Chemistry).
2. Miyaura, N.; Suzuki, A. Palladium-Catalyzed Cross-Coupling Reactions of Organoboron Compounds. Chem. Rev. 1995, 95, 2457–2483. doi:10.1021/cr00039a007
3. Hartwig, J. F. Carbon–Heteroatom Bond Formation Catalysed by Organometallic Complexes. Nature 2008, 455, 314–322. doi:10.1038/nature07369
4. Moriarty, R. M. et al. Cyclopropyl group as a pharmacophore in medicinal chemistry — general textbook and review literature; specific citations require verification.

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