The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 03, 1985
Filed:
May. 10, 1982
Applicant:
Inventors:
Philip H Merrell, Arnold, MO (US);
Michael F Ellis, Hazelwood, MO (US);
Assignee:
Mallinckrodt, Inc., St. Louis, MO (US);
Primary Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
564430 ; 564423 ;
Abstract
Diaminodiphenyl ethers (DADPE's) are prepared by refluxing sodium or potassium aminophenate with chloronitrobenzene 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.