Understanding the intrinsic physicochemical properties of a chemical compound is fundamental to its successful application, particularly in sensitive fields like pharmaceuticals and advanced materials. This article provides a comprehensive overview of the properties and stability of 5-Chloropyrazolo[1,5-a]pyrimidine-3-Carbonitrile (CAS: 1224288-92-9), a key intermediate known for its value in organic synthesis and drug discovery.

Structurally, 5-Chloropyrazolo[1,5-a]pyrimidine-3-Carbonitrile features a rigid, planar fused bicyclic system comprising pyrazole and pyrimidine rings. The presence of a chlorine atom at the 5-position and an aldehyde group at the 3-position significantly influences its electronic distribution, reactivity, and intermolecular interactions. Crystallographic and computational analyses confirm the planarity of the core structure and reveal potential for hydrogen bonding and π-π stacking, which are critical for its solid-state behavior and crystal packing.

Solubility is a key consideration for reaction and formulation processes. While specific quantitative data for this exact compound can vary, related pyrazolo[1,5-a]pyrimidine derivatives generally exhibit moderate solubility in polar aprotic solvents, with solubility influenced by substituent polarity. The aldehyde group contributes to its capacity for hydrogen bonding, affecting its dissolution in protic media.

Thermal stability is another vital parameter. Aromatic heterocyclic compounds like this generally possess good thermal resilience. For related structures, decomposition temperatures are often observed above 250°C. However, the aldehyde functional group can be susceptible to thermal and oxidative degradation. Recommendations for storage at refrigerated temperatures (2-8°C) under an inert atmosphere are crucial for minimizing oxidative processes and preserving the compound's integrity over time. This careful handling is essential to maintain its high purity, often exceeding 98%.

The green chemistry metrics associated with its synthesis further underscore its practical value. Methods like microwave-assisted synthesis and the Vilsmeier-Haack reaction are optimized for high yields, reduced solvent usage, and improved atom economy, making the production process more sustainable. This focus on environmentally benign practices is increasingly important in the chemical industry.

In summary, 5-Chloropyrazolo[1,5-a]pyrimidine-3-Carbonitrile is characterized by its stable heterocyclic core, reactive functional groups, and favorable physicochemical properties. A thorough understanding of its solubility, thermal, and oxidative stability, alongside its synthetic accessibility, ensures its effective and reliable application in pharmaceutical development, agrochemical synthesis, and advanced organic chemistry research. Careful handling and storage are recommended to maintain its high quality for all applications.