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:
Feb. 25, 1992
Filed:
Mar. 27, 1991
Applicant:
Inventors:
R Garth Pews, Midland, MI (US);
James A Gall, Sanford, MI (US);
Assignee:
DowElanco, Indianapolis, IN (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
564407 ; 570143 ; 570147 ;
Abstract
2,6-Difluoroaniline is prepared from 1,2,3-trichlorobenzene by partial fluorine exchange to a mixture of 2,6-difluorochlorobenzene and 2,3-difluorochlorobenzene, amination of the chloro substituents, and separation of the desired product from the isomeric 2,3-difluoroaniline. By incorporating a selective reduction into the process immediately after the partial fluorine exchange, the undesirable 2,3-difluorochlorobenzene is converted into valuable ortho-difluorobenzene and the 2,3-difluoroaniline isomer is avoided.