5-Bromo-2,4-dichloropyrimidine
[CAS# 36082-50-5]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Pyrimidine compound >> Chloropyrimidine
• Name: 5-Bromo-2,4-dichloropyrimidine
• Molecular Formula: C₄HBrCl₂N₂
• Molecular Weight: 227.87
• CAS Registry Number: 36082-50-5
• EC Number: 629-358-1
• SMILES: C1=C(C(=NC(=N1)Cl)Cl)Br

Properties

• Density: 1.781 g/mL (Expl.)
• Melting point: 29-30 °C (Expl.)
• Index of Refraction: 1.603 (Expl.)
• Boiling point: 128 °C (15 mmHg) (Expl.)
• Flash point: 113 °C (15 mmHg) (Expl.)

Safety Data

• Hazard Symbols: GHS05;GHS06;GHS07 Danger
• Risk Statements: H301+H311+H331-H301-H311-H314-H317-H331
• Safety Statements: P260-P261-P262-P264-P270-P271-P272-P280-P301+P316-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P321-P330-P333+P317-P361+P364-P362+P364-P363-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin corrosion	Skin Corr.	1B	H314
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	3	H311
Acute toxicity	Acute Tox.	3	H331
Skin sensitization	Skin Sens.	1	H317
Serious eye damage	Eye Dam.	1	H318
Specific target organ toxicity - single exposure	STOT SE	3	H335

• Transport Information: UN 3263

Discovery and Applications

5-Bromo-2,4-dichloropyrimidine is a halogenated pyrimidine derivative, which is a member of the pyrimidine family of organic compounds that contain nitrogen atoms within a six-membered ring structure. The chemical formula of 5-bromo-2,4-dichloropyrimidine is C4H2BrCl2N2, and it is commonly used in various applications within synthetic chemistry, agrochemicals, and pharmaceuticals due to its reactivity and functional properties.

The discovery of 5-bromo-2,4-dichloropyrimidine dates back to the early 20th century, when the chemistry of pyrimidine derivatives began to be explored for their potential applications in medicinal chemistry and agriculture. Pyrimidine compounds, being structurally similar to purines and involved in key biochemical processes, attracted attention for their role in the synthesis of nucleic acids and their potential pharmacological activities. The halogenation of pyrimidine rings, particularly at the 2,4, and 5 positions, has been an important synthetic strategy to enhance the reactivity and functional diversity of pyrimidine derivatives.

5-Bromo-2,4-dichloropyrimidine is synthesized through various halogenation methods involving the introduction of bromine and chlorine atoms onto the pyrimidine ring. This can be achieved by reacting pyrimidine with brominating agents such as NBS (N-Bromosuccinimide) and chlorinating agents like chlorine gas or phosphorus trichloride under controlled conditions. The presence of the halogen atoms at the 2,4, and 5 positions of the pyrimidine ring imparts distinctive reactivity to the compound, making it valuable in several chemical reactions.

One of the key applications of 5-bromo-2,4-dichloropyrimidine is in the field of medicinal chemistry, where it serves as an important intermediate in the synthesis of pharmaceuticals. The halogenated pyrimidine core structure is a common feature in many biologically active molecules, including antiviral, anticancer, and anti-inflammatory drugs. For example, derivatives of 5-bromo-2,4-dichloropyrimidine have been explored for their potential as inhibitors of enzymes involved in cellular processes, such as kinases and DNA polymerases. These properties make it a promising candidate for the development of new therapeutic agents aimed at treating a variety of diseases, including cancer and viral infections.

In the agrochemical industry, 5-bromo-2,4-dichloropyrimidine is used as a building block in the design of herbicides and fungicides. The halogenated pyrimidine structure has been found to exhibit herbicidal and fungicidal activity, and its derivatives are often more selective and effective compared to unmodified pyrimidine compounds. The presence of the bromine and chlorine atoms enhances the molecule's lipophilicity, which allows for better absorption by plants and fungi, improving the effectiveness of the pesticide.

In organic synthesis, 5-bromo-2,4-dichloropyrimidine is used as a starting material for the preparation of other functionalized pyrimidine derivatives. It can undergo a variety of reactions, such as nucleophilic substitution, cross-coupling reactions, and condensation, to yield compounds with diverse functionalities. The ability to introduce additional functional groups onto the pyrimidine ring makes this compound a versatile intermediate for synthesizing molecules with specialized properties for various applications in materials science and fine chemicals.

Furthermore, 5-bromo-2,4-dichloropyrimidine has also been utilized in the synthesis of heterocyclic compounds, which are often studied for their electronic properties and potential use in organic electronics, including OLEDs (organic light-emitting diodes). The incorporation of halogen atoms into heterocyclic systems has been shown to modify their electronic properties, which is advantageous for developing advanced materials for optoelectronic devices.

In conclusion, 5-bromo-2,4-dichloropyrimidine is an important halogenated pyrimidine derivative with diverse applications in medicinal chemistry, agrochemicals, and organic synthesis. Its halogenation at specific positions on the pyrimidine ring enhances its reactivity, making it a versatile intermediate in the synthesis of biologically active molecules and functionalized materials. Ongoing research into its derivatives continues to reveal new uses for this compound in drug development and materials science, highlighting its importance in chemical synthesis.

References

2020. Halogenated Pyrimidines in Synthesis. Journal of Heterocyclic Chemistry, 57(8).
DOI: 10.1002/jhet.3987