Description

4-Hydroxyphthalic Acid is a versatile aromatic dicarboxylic acid derivative, distinguished by the presence of a hydroxyl group on the phthalic acid backbone. This unique structure makes it a valuable building block and intermediate for synthesizing complex organic molecules, including pharmaceuticals, dyes, and advanced polymers. It is essential for manufacturers and R&D teams in the pharmaceutical, agrochemical, and specialty chemical industries seeking to develop new compounds with specific functional properties.

Application

• Pharmaceutical Intermediate: A key precursor in the synthesis of active pharmaceutical ingredients (APIs), particularly for compounds requiring a functionalized aromatic core.
• Dye and Pigment Manufacturing: Serves as a starting material for producing complex organic dyes, colorants, and fluorescent markers.
• Polymer Chemistry: Used as a monomer or cross-linking agent in the production of specialty polyesters, epoxy resins, and other high-performance polymers.
• Agrochemical Synthesis: An important intermediate for creating herbicides, fungicides, and plant growth regulators.
• Chemical Research & Development: Employed in organic synthesis for constructing complex molecular architectures in academic and industrial labs.
• Complexing Agent: Can act as a ligand in metal-organic frameworks (MOFs) or catalysts due to its carboxylic and hydroxyl functional groups.

Basic Information

Product Name	4-Hydroxyphthalic Acid
CAS No.	610-35-5
Molecular Formula	C8H6O5
Molecular Weight	182.13 g/mol
Synonyms	4-Hydroxybenzene-1,2-dicarboxylic Acid; 1,2-Benzenedicarboxylic Acid, 4-Hydroxy-; 4-Carboxy-2-hydroxybenzoic Acid; 2-Hydroxyterephthalic Acid; 4-Hydroxyisophthalic Acid (common misnomer); 4-HPA; 4-Hydroxyphthalate
EINECS	210-221-0

Quality Control

Our 4-Hydroxyphthalic Acid is produced under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets high-purity standards suitable for industrial and research applications. Certificates of Analysis (COA) detailing purity, identity, and impurity profiles are available upon request to support your quality assurance and regulatory compliance needs.

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). The product may be hygroscopic (moisture-sensitive); keep the container tightly sealed when not in use to prevent absorption of atmospheric moisture.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Melting Point	210°C - 215°C
Loss on Drying	≤ 0.5%
Heavy Metals (as Pb)	≤ 10 ppm
Residue on Ignition	≤ 0.1%

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