Method for isomerization of trans-form 2-methylspiro- (1,3-oxathiolane-5,3')quinuclidine or acid addition salts thereof
CA 1331183 C · Owner: Ishihara Sangyo Kaisha Ltd. · Inventors: Hara, Kazutoshi; Koyanagi, Toru; Maeda, Masaru
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for isomerization of trans-form 2-methylspiro(1,3-oxathiolane-5,3')quinuclidine or acid addition salts thereof, which comprises isomerizing said trans-form quinuclidine or acid addition salts thereof to cis-form 2-methylspiro(1,3-oxathiolane-5,3')quinuclidine or acid addition salts thereof in the presence of at least one acid catalyst selected from the group consisting of an organic sulfonic acid, a halide functioning as a Lewis acid, and sulfuric acid.
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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
- Granted August 2, 1994. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 2, 2011.
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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.