A process for the preparation of 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethanol
CA 2020920 C · Owner: Atochem · Inventors: Sola, Jaume C.; Adrubau, Jaime P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed is a process for the preparation of 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethanol (known as p p'-dicofol), starting out from a mixture containing this compound, i.e. 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethanol, in admixture with at least one compound selected from the group consisting of 1-(4-chlorophenyl)-1-(2-chlorophenyl)-2,2,2-trichloroethanol (known as o,p'-dicofol); 1-(4-chlorophenyl)-1-(2-chlorophenyl)-2,2,2-trichloroethane (known as o,p'-DDT); and 1-(4-chlorophenyl)-1-(2-chlorophenyl)-2,2-dichloroethylene (known as o,p'-DDE). This process which permits to separate biologically active p,p'-dicofol in large yield from raw dicofol basically comprises, the formation of …
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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 July 11, 1990 and granted December 7, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 11, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 11, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.