For professionals engaged in the synthesis of dyes, pharmaceuticals, and other fine chemicals, understanding the intrinsic properties of key intermediates is fundamental. 1,5-Dihydroxynaphthalene (CAS 83-56-7) is a prime example of such a compound, whose specific characteristics dictate its utility and performance in various chemical manufacturing processes. As a B2B audience, buyers and formulators must be attuned to these properties to ensure they source material that meets stringent industrial requirements. This article highlights the critical properties of 1,5-Dihydroxynaphthalene and what to consider when purchasing.

Physical Characteristics and Purity Standards

The most commonly observed physical characteristic of 1,5-Dihydroxynaphthalene is its form as a grey-white powder. This appearance is a primary indicator for initial identification. However, the true measure of its quality for industrial use lies in its purity. Reputable manufacturers typically offer this compound with a minimum purity of 99%. For applications where even trace impurities can cause significant issues, such as in advanced pharmaceutical synthesis or high-performance dyes, confirming this purity level through a Certificate of Analysis (CoA) from the supplier is non-negotiable. Variations in color, from pale beige to very dark brown, might be noted in some sources, but a consistent grey-white is generally preferred for high-grade material.

Thermal Stability and Reactivity

1,5-Dihydroxynaphthalene possesses a notable thermal stability, evidenced by its high melting point, often cited in the range of 259-261°C (with decomposition). This characteristic is important for processes that involve elevated temperatures during synthesis or purification. Its chemical reactivity is primarily driven by the two hydroxyl (-OH) groups attached to the naphthalene rings. These groups make it susceptible to electrophilic aromatic substitution reactions and allow it to act as a coupling agent, which is fundamental to its role in producing azo dyes. The compound can also undergo amination and oxidation reactions, further broadening its synthetic utility.

Solubility and Handling Considerations

Understanding the solubility profile of 1,5-Dihydroxynaphthalene is crucial for designing effective reaction and purification procedures. It is generally sparingly soluble in water but exhibits good solubility in common organic solvents like acetone and ether. This differential solubility can be leveraged during isolation and purification steps. Safety Data Sheets (SDS) are vital for handling instructions, providing information on potential hazards (such as skin and eye irritation) and necessary personal protective equipment (PPE). Safe storage, typically in a cool, dry place, and in tightly sealed containers, is recommended to maintain product integrity and prevent degradation or oxidation.

Key Takeaways for Buyers

When sourcing 1,5-Dihydroxynaphthalene, buyers should prioritize suppliers who transparently provide detailed specifications, including:

  • Purity (≥99%)
  • CAS Number (83-56-7)
  • Melting Point
  • Appearance
  • Solubility data
  • Availability of CoA and SDS

Engaging with manufacturers that can guarantee consistent product quality and reliable supply, especially for bulk purchases in standard packaging like 25kg drums, is key to successful industrial operations.