Synthetic methodology for the development of 4-ADPA. 4-Aminodiphenylamine (4-ADPA) is a key building block for rubber preservatives. Many aromatic amines are made with halogenated reagents, especially those containing chlorine. The Eastman Chemical Company's previous production of 4-ADPA is based on the chlorination of benzene. This process produced aqueous waste with high levels of inorganic salts that are difficult and expensive to treat. This process also required the storage and handling of large quantities of chlorine gas, which is hazardous to human health. The Eastman Chemical Company now uses a class of reactions called the nucleophilic aromatic substitution of nitrogen (NASH) to synthesize these aromatic amines without halogenated reagents. The manufacturing of 4-ADPA uses the NASH process, aniline, and nitrobenzene. This new process reduces organic waste by 74%, inorganic waste by 99%, and wastewater by 94%. If 30% of the world's 4-ADPA producers converted to this process, the industry would decrease chemical waste by 74 million pounds and wastewater by 1.4 million pounds.
EPA Presidential Green Chemistry Challenge: 1998 Greener Synthetic Pathways Award
Flexsys America L.P.
