Description

4,5-Dichlorophthalic Anhydride is a halogenated aromatic anhydride derivative that serves as a critical high-purity intermediate in advanced chemical synthesis. This compound matters for its role as a versatile building block, enabling the introduction of the dichlorophthaloyl moiety to impart specific chemical and physical properties to target molecules. It is primarily needed by manufacturers in the pharmaceutical, agrochemical, and specialty polymer industries for applications ranging from active pharmaceutical ingredient (API) development to the creation of high-performance materials.

Application

• Pharmaceutical Intermediate: Key building block in the synthesis of complex drug molecules, particularly those requiring a halogenated phthalimide or phthalamic acid structure.
• Agrochemical Synthesis: Used in the production of advanced herbicides, fungicides, and plant growth regulators where the dichloro-substitution enhances biological activity.
• Polymer & Resin Modifier: Incorporated into polyimides, epoxy resins, and alkyd resins to improve thermal stability, flame retardancy, and chemical resistance.
• Dye & Pigment Manufacturing: Intermediate for the synthesis of high-value, color-fast pigments and dyes, especially phthalocyanine derivatives.
• Organic Synthesis Reagent: Employed in research and development for creating novel heterocyclic compounds and as a derivatization agent in analytical chemistry.

Basic Information

Product Name	4,5-Dichlorophthalic Anhydride
CAS No.	942-06-3
Molecular Formula	C8H2Cl2O3
Molecular Weight	217.00 g/mol
Synonyms	4,5-Dichlorophthalic Acid Anhydride; 4,5-Dichloro-1,3-isobenzofurandione; 4,5-Dichlorophthalic Anhydride; 1,3-Dioxo-4,5-dichloroisobenzofuran; NSC 403108; 4,5-Dichlorobenzene-1,2-dicarboxylic Anhydride; Phthalic Anhydride, 4,5-dichloro-
EINECS	213-369-1

Quality Control

Our 4,5-Dichlorophthalic Anhydride is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing to ensure it meets high-purity standards suitable for sensitive synthetic applications. A comprehensive Certificate of Analysis (COA) detailing purity, identity, and impurity profiles is 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 a controlled room temperature (15-25°C). Due to its hygroscopic (moisture-sensitive) nature, the container must be kept tightly sealed to prevent degradation from atmospheric moisture.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Melting Point	185 - 190 °C
Loss on Drying	≤ 0.5%
Residue on Ignition	≤ 0.1%
Heavy Metals (as Pb)	≤ 20 ppm

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