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:
Dec. 25, 2007
Filed:
Jan. 13, 2004
Applicants:
Dongchao Wang, Yangzhou, CN;
Youfa Jiang, Yangzhou, CN;
Inventors:
Dongchao Wang, Yangzhou, CN;
Youfa Jiang, Yangzhou, CN;
Assignee:
Jiangsu Yangong Chemical Co., Ltd., Yangzhou, Jiangsu, CN;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 33/26 (2006.01); C07C 69/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
Methods for preparing 2,3,5,6-tetrafluorodimethylolbenzene, an intermediate for the preparation of pyrethroids, are disclosed. A method for preparing 2,3,5,6-tetrafluorodimethylolbenzene includes the reduction of tetrafluoroterephthalate. Various reduction processes are disclosed, which are simple and safe and can afford the product in high yield and purity. Processes for preparing tefluthrin from 2,3,5,6-tetrafluorodimethylolbenzene, by halogenation, hydrogenation, and esterification, are also disclosed.