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:
Mar. 07, 2000
Filed:
Dec. 18, 1998
Vidyanatha A Prasad, Leawood, KS (US);
Thomas Schmidt, Haan, DE;
Peter E Newallis, Leawood, KS (US);
Bayer Corporation, Pittsburgh, PA (US);
Bayer Aktiengesellschaft, Leverkusen, DE;
Abstract
The present invention provides a process for making 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole. The process includes the steps of reacting methyidithiocarbazinate with trifluoroacetic acid, in the absence of phosphorus trichloride, to form a mixture of 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole and 2,5-bis-(methylthio)-1,3,4-thiadiazole. Further, the process of the present invention includes selectively removing the 2,5-bis-(methylthio)-1,3,4-thiadiazole by acidifying the reaction mixture, and then separating the aqueous and organic phases.