Description

4-Hydroxyphthalic Anhydride is a versatile and reactive organic intermediate of significant industrial importance. Its unique bifunctional structure, featuring both an anhydride and a phenolic hydroxyl group, makes it a valuable building block for synthesizing complex molecules with tailored properties. This compound is essential for manufacturers in the pharmaceutical, agrochemical, and advanced polymer industries seeking to develop high-performance materials and active ingredients.

Application

• Pharmaceutical Intermediate: Key precursor in the synthesis of active pharmaceutical ingredients (APIs), particularly for compounds with complex polycyclic structures.
• Agrochemical Synthesis: Used in the production of advanced herbicides, fungicides, and plant growth regulators.
• Polymer & Resin Modifier: Serves as a monomer or cross-linking agent for epoxy resins, polyimides, and other high-temperature polymers, enhancing thermal stability and mechanical properties.
• Dye & Pigment Manufacturing: Intermediate for producing specialized phthalocyanine dyes and organic pigments.
• Liquid Crystal & OLED Materials: Building block for synthesizing charge-transport materials and other functional components in electronic displays.
• Fine Chemical Synthesis: Versatile starting material for creating complex esters, amides, and other derivatives in custom synthesis projects.

Basic Information

Product Name	4-Hydroxyphthalic Anhydride
CAS No.	27550-59-0
Molecular Formula	C8H4O4
Molecular Weight	164.12 g/mol
Synonyms	4-Hydroxy-1,3-isobenzofurandione; 4-Hydroxyphthalic acid cyclic anhydride; 1,3-Dioxo-1,3-dihydro-2-benzofuran-5-ol; 5-Hydroxyisobenzofuran-1,3-dione; 4-Hydroxyphthalic acid anhydride; 5-Hydroxyphthalic anhydride; 4-Carboxy-2-hydroxybenzoic acid anhydride
EINECS	Contact for details

Quality Control

Our 4-Hydroxyphthalic Anhydride is manufactured under a stringent quality management system. Each batch undergoes comprehensive analytical testing, including HPLC for purity and identity confirmation (IR), to ensure it meets exacting specifications for critical applications. Certificates of Analysis (COA) documenting all test results are provided with every shipment to guarantee traceability and batch-to-batch consistency.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry, and well-ventilated area at room temperature (15-25°C). This product is hygroscopic (moisture-sensitive) and must be kept under dry conditions to prevent decomposition. Keep away from strong bases and oxidizing agents.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to reference spectrum
Assay (HPLC)	≥ 98.0%
Melting Point	185 - 190 °C
Loss on Drying	≤ 1.0 %
Heavy Metals	≤ 20 ppm

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.