4-Chloro-7H-pyrrolo[2,3-d]pyrimidine is an important heterocyclic compound in the field of medicinal and organic chemistry. It serves as a core structure in various biologically active molecules, particularly in the development of kinase inhibitors, antiviral agents, and other pharmaceutical intermediates. This article provides an overview of its structure, physical properties, and basic chemical characteristics.
Molecular Formula: C6H4ClN3
Molecular Weight: ~153.57 g/mol
Chemical Class: Heteroaromatic halide
Structure: The compound features a fused bicyclic ring system containing a pyrrole ring and a pyrimidine ring, with a chlorine atom substituted at the 4-position.
IUPAC Name: 4-Chloro-7H-pyrrolo[2,3-d]pyrimidine
The bicyclic arrangement imparts rigidity and planarity to the molecule, making it a versatile scaffold for further functionalization.
Appearance: Light-colored to off-white crystalline solid
Melting Point: Typically ranges from 170–175 °C
Solubility: Soluble in organic solvents such as DMSO, DMF, and ethanol; sparingly soluble in water
Boiling Point: Decomposes before boiling
Stability: Stable under normal storage conditions, but sensitive to strong acids, bases, or prolonged exposure to moisture
The presence of the chlorine atom makes the molecule reactive towards nucleophiles, enabling diverse substitution reactions.
The chemistry of 4-Chloro-7H-pyrrolo[2,3-d]pyrimidine is largely influenced by:
Electron-withdrawing chlorine at the 4-position, which enhances the electrophilicity of the ring.
Heteroatoms in the ring system (nitrogen atoms) that can participate in hydrogen bonding and influence electronic distribution.
Key reactions include:
Nucleophilic substitution (SNAr): The chlorine atom can be replaced by amines, thiols, or alkoxides to generate a variety of derivatives.
Cross-coupling reactions: Such as Suzuki, Stille, or Buchwald–Hartwig couplings, enabling the introduction of diverse substituents.
Heterocyclic functionalization: Modifications at the pyrrole ring for structure–activity relationship (SAR) studies in drug design.
4-Chloro-7H-pyrrolo[2,3-d]pyrimidine is widely used as:
A pharmaceutical intermediate in the synthesis of kinase inhibitors for cancer therapy.
A building block for antiviral and anti-inflammatory agents.
A scaffold for structure–activity exploration in medicinal chemistry.
Its versatile reactivity makes it an attractive starting point for creating novel heteroaromatic compounds.
Hazards: May cause skin, eye, or respiratory irritation.
Precautions: Use in a well-ventilated laboratory with appropriate PPE (gloves, goggles, lab coat).
Storage: Keep in a tightly sealed container, in a cool, dry place, away from moisture and incompatible chemicals.
4-Chloro-7H-pyrrolo[2,3-d]pyrimidine is a valuable heterocyclic compound with significant importance in medicinal chemistry. Its unique fused-ring structure, halogen substitution, and diverse reactivity make it a key building block in the synthesis of potential therapeutic agents. Understanding its properties and chemistry opens opportunities for innovations in drug discovery and chemical research.
