Tetrahydropyran (THP), identified by CAS number 142-68-7, is a versatile cyclic ether with widespread use in organic synthesis, pharmaceuticals, and as a specialized solvent. For procurement managers, R&D scientists, and product formulators, understanding the critical specifications of Tetrahydropyran is fundamental to ensuring product quality, process efficiency, and successful application outcomes. This guide outlines the key parameters to consider when evaluating Tetrahydropyran for purchase.

Key Specifications for Tetrahydropyran:

  • Purity/Assay: This is arguably the most critical specification. Tetrahydropyran is typically sold with a minimum purity of 99.0%. However, for demanding applications like pharmaceutical intermediates, higher purities, often exceeding 99.5% or even 99.90%, are required. A Certificate of Analysis (CoA) from the manufacturer should clearly state the assay value and the analytical method used (e.g., Gas Chromatography - GC).
  • Appearance: Tetrahydropyran is characterized by its appearance. Manufacturers commonly describe it as a 'colorless transparent liquid'. Any deviation from this, such as the presence of color or turbidity, can indicate impurities or degradation, suggesting potential issues with storage or manufacturing.
  • Water Content: Water can interfere with many organic reactions, particularly those involving moisture-sensitive reagents like Grignard reagents. Therefore, the water content is a crucial specification, often measured in parts per million (ppm). Low water content (e.g., ≤100 ppm) is desirable for many applications.
  • Color: While appearance covers transparency, color is often specified on a scale like APHA (American Public Health Association). A low APHA value (e.g., ≤10.00) indicates a near-colorless product, which is preferred.
  • Boiling Point and Melting Point: These physical properties are important for understanding Tetrahydropyran's behavior under different temperature conditions and for process design. The boiling point is around 88°C, and the melting point is approximately -45°C.
  • Refractive Index: The refractive index is another physical property that can be used to verify the identity and purity of Tetrahydropyran.
  • Flash Point: As a flammable liquid, the flash point (approximately 4°F or -15.6°C) is a critical safety parameter that must be clearly communicated and understood for handling and storage.
  • Other Impurities: Depending on the intended application, specific limits may be set for other known impurities, such as peroxides, which can form in ethers upon exposure to air and light.

Ensuring Quality When You Purchase Tetrahydropyran:

When you buy Tetrahydropyran, always request a detailed CoA from the Tetrahydropyran supplier. This document provides the verified specifications for the batch you are purchasing. For critical applications, consider having independent third-party analysis performed, especially when sourcing from new manufacturers. Building a strong relationship with a reliable Tetrahydropyran manufacturer, particularly one known for its quality control and transparency in China, is key to consistently obtaining Tetrahydropyran that meets your exact needs.