Trifluoro- and chlorodifluoromethoxypyrimidines and the preparation thereof
CA 2037733 C · Owner: Basf Aktiengesellschaft · Inventors: Wolf, Hans-Josef; Hamprecht, Gerhard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Substituted trifluoro- and chlorodifluoromethoxypyrimidines of the formula (I):, (see formula I), where R1 R2 and R3 are each, independently of one another hydrogen, halogen or haloalkyl, and R1 and/or R2 are also trifluoromethoxy or chlorodifluoromethoxy and n is 0 or 1, are prepared as described. These compounds are useful as intermediates for preparing organic compounds and, especially for preparing herbicidal sulfonylureas.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed March 7, 1991 and granted December 25, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 7, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.