Process for isomerizing endo-form of aromatic group-containing norbornenes to exo-form thereof, isomer mixture of aromatic group-containing norbornenes and process for preparing same, and ethylene/aromatic group-contain ng norbornene copolymer and process for preparing same
CA 2061003 C · Owner: Mitsui Chemicals, Inc. · Inventors: Toda, Yoshihisa; Sagane, Toshihiro; Tsuji, Yoichiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for isomerization of an endo-form of aromatic group-containing norbornenes represented by the following formula (I) to an exo-form which comprises bringing the endo-form into contact with a solid acid catalyst. wherein p is 0 or an integer of 1 or more q and r are each, 0,1 or 2, R1 to R15 are each independently hydrogen or halogen atom, aliphatic hydrocarbon group, aromatic hydrocarbon group or alkoxy group, R5 (or R6) are R9 (or R7) may be linked together through an alkylene group of 1-3 carbons or may be directly linked together.
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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 February 11, 1992 and granted February 9, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 11, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 11, 2014.
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Timeline
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.