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. 08, 1987
Filed:
May. 02, 1986
Robert Hassig, Sisseln, CH;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
The present invention relates to a process for the preparation of 2-mercapto-4,6-bis-fluoroalkoxypyrimidines of the formula ##STR1## wherein R.sub.1 is C.sub.1 -C.sub.4 alkyl, phenyl or benzyl and each of T.sub.1 and T.sub.2 independently of the other is hydrogen or a --CHX.sub.1 X.sub.2 group, wherein each of X.sub.1 and X.sub.2 independently of the other is trifluoromethyl, fluorine, chlorine or bromine. In accordance with this process, 2-mercapto-4-halo-6-hydroxy-pyrimidines of the formula ##STR2## wherein R.sub.1 is as defined above and Y is chlorine or bromine, are reacted with chlorodifluoromethane or a 1,1-difluoroalkene of the formula ##STR3## wherein each of the X.sub.1 and X.sub.2 independently of the other is trifluoromethyl, fluorine, chlorine or bromine, in an inert solvent and in the presence of a strong base, to give a 2-mercapto-4-halo-6-fluoro-alkoxypyrimidine of the formula ##STR4## wherein R.sub.1, Y and T.sub.1 are as defined above, said 2-mercapto-4-halo-6-fluoroalkoxypyrimidine is converted by subsequent reaction with an alkali metal nitrite or an alkaline earth metal nitrite into a 2-mercapto-4-hydroxy-6-fluoroalkoxypyrimidine of the formula ##STR5## wherein R.sub.1 and T.sub.1 are as defined above, and then said 2-mercapto-4-hydroxy-6-fluoroalkoxypyrimidine is converted by reaction with chlorodifluoromethane or a 1,1-difluoroalkene of the above formula into a 2-mercapto-4,6-bix-fluoroalkoxypyrimidine of the above formula. The 2-mercapto-4,6-bis-fluoroalkoxypyrimidines of the above formula are intermediates for the preparation of herbicidally effective sulfonylureas.