| abstract |
Diaminodiphenyl ethers (DADPE's) are prepared by refluxing sodium or potassium aminophenate with halonitrobenzene in dimethylformamide. The reaction mixture is hydrogenated directly without isolating the resulting intermediate product, aminophenyl-nitrophenyl ether, to form the corresponding DADPE, e.g., oxydianiline (ODA). The DADPE is crystallized from the hydrogenated reaction mixture in the presence of an aliphatic alcohol, which may be added to the reaction mixture prior to, during, or after hydrogenation. The resulting crystallized DADPE is typically of high purity and excellent color. |