Description

1,3-Dioxo-1,3-Dihydro-Isobenzofuran-4-Carboxylic Acid is a versatile and high-purity organic building block, also known as 4-Carboxyphthalic anhydride. Its unique structure makes it a critical intermediate for synthesizing complex molecules, offering precise control over final product properties. This compound is essential for research and production in advanced material science and fine chemical manufacturing. Industries requiring high-performance additives, specialty polymers, and active pharmaceutical ingredients (APIs) rely on its consistent quality and reactivity.

Application

• Pharmaceutical Intermediate: A key precursor in the synthesis of active pharmaceutical ingredients (APIs), particularly for compounds with phthalimide or phthalic anhydride cores.
• Polymer & Resin Modifier: Used to introduce carboxylic acid functionality into polymer chains, enhancing properties like adhesion, cross-linking density, and thermal stability for advanced coatings and composites.
• Organic Synthesis Building Block: Serves as a versatile reagent for constructing complex heterocyclic compounds, dyes, and pigments in fine chemical production.
• Liquid Crystal & Electronic Material Precursor: Employed in the development of specialty monomers for liquid crystal polymers (LCPs) and other high-performance electronic materials.
• Agrochemical Synthesis: Acts as an intermediate in the manufacture of certain herbicides and plant growth regulators.
• Cross-linking Agent: Functions as a cross-linker in epoxy and other thermosetting resin systems to improve mechanical strength and chemical resistance.
• Analytical Reagent & Standard: Used as a standard or reagent in chromatographic analysis and quality control laboratories.

Basic Information

Product Name	1,3-Dioxo-1,3-Dihydro-Isobenzofuran-4-Carboxylic Acid
CAS No.	3786-39-8
Molecular Formula	C9H4O5
Molecular Weight	192.12 g/mol
Synonyms	4-Carboxyphthalic Anhydride; 1,3-Dioxo-1,3-dihydroisobenzofuran-4-carboxylic acid; 4-Carboxy-1,3-dihydroisobenzofuran-1,3-dione; 4-Carboxybenzene-1,2-dicarboxylic anhydride; Phthalic Anhydride-4-carboxylic Acid; 1,2,4-Benzenetricarboxylic acid 1,2-anhydride; 4-CBA (context-specific); Monopotassium 1,3-dioxo-1,3-dihydro-2-benzofuran-4-carboxylate (salt form)
EINECS	223-257-5

Quality Control

Our 1,3-Dioxo-1,3-Dihydro-Isobenzofuran-4-Carboxylic Acid is manufactured under a strict quality management system. Each batch undergoes rigorous analytical testing, including HPLC for purity and identity confirmation, to ensure it meets the high standards required for pharmaceutical and fine chemical applications. A comprehensive Certificate of Analysis (COA) detailing assay, impurity profile, and physical characteristics is provided with every shipment to guarantee traceability and compliance.

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 after opening to prevent degradation from atmospheric moisture. Keep away from incompatible materials such as strong bases and oxidizing agents.

Specification

Item	Specification
Appearance	White to off-white crystalline powder
Identification (IR)	Conforms to structure
Assay (HPLC)	≥ 98.0%
Melting Point	215 - 220 °C
Loss on Drying	≤ 1.0%
Heavy Metals (as Pb)	≤ 20 ppm
Residue on Ignition	≤ 0.1%
Related Substances (HPLC)	Total impurities ≤ 2.0%

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