Understanding the fundamental properties and reliable manufacturing processes of chemical intermediates is crucial for their effective utilization across various industries. 3-Nitrophthalic Anhydride, identified by its CAS number 641-70-3, is a compound that has garnered significant attention due to its versatile chemical nature and broad application spectrum. This article delves into the physical and chemical attributes of 3-Nitrophthalic Anhydride, alongside insights into its synthesis and the critical importance of quality assurance in its production.

Physically, 3-Nitrophthalic Anhydride typically presents as a beige to yellow crystalline powder. Its melting point is generally recorded in the range of 163-165°C, a key characteristic that influences its handling and processing. Chemically, the compound's molecular formula is C8H3NO5, with a molecular weight of 193.11 g/mol. The presence of the nitro group (–NO2) significantly impacts its electronic properties, making the anhydride ring more reactive towards nucleophilic substitution reactions. It is known to be sensitive to moisture and may decompose upon prolonged contact with water, necessitating careful storage in tightly sealed containers in a cool, dry environment.

The synthesis of 3-Nitrophthalic Anhydride often involves the nitration of phthalic anhydride using a nitrating mixture, such as concentrated nitric acid and sulfuric acid. This process can yield a mixture of isomers, from which the desired 3-nitrophthalic anhydride must be isolated and purified. Alternatively, it can be prepared by dehydrating 3-nitrophthalic acid, typically using acetic anhydride at elevated temperatures. The efficiency and purity of the final product are heavily dependent on precise control over reaction conditions, including temperature, reagent ratios, and reaction time. Post-synthesis purification methods, such as recrystallization, are employed to achieve the high purity levels (often exceeding 98%) required for its applications, particularly in the pharmaceutical industry.

Quality assurance is a cornerstone in the manufacturing of 3-Nitrophthalic Anhydride. Rigorous testing is conducted to verify its identity, purity, and physical characteristics. This includes techniques like High-Performance Liquid Chromatography (HPLC) for purity assessment, Infrared (IR) spectroscopy for structural confirmation, and melting point determination. Certificates of Analysis (CoA) accompany the product, detailing these specifications and ensuring traceability. Reliable suppliers like NINGBO INNO PHARMCHEM CO.,LTD. place a strong emphasis on these quality control measures, ensuring that their 3-Nitrophthalic Anhydride meets the demanding standards of their global clientele. This commitment to quality ensures that the compound performs optimally in downstream applications, from pharmaceutical synthesis to the creation of advanced materials.