Process for the production of .gamma.-keto acetals
CA 2496225 C · Owner: Kojima, Shunshi · Inventors: Kojima, Shunshi; Okazaki, Rei
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Subject , The present invention provides a process for the production of a .gamma.ketoacetal , compound wherein the desired product can be obtained through a simple procedure in , high yield as a high purity product. Means to solve the subject The present invention is a process in which the reaction scheme is shown below: , (see above reaction scheme), (wherein Ar is an aryl group; X is a halogen atom; R a and R b are alkyl groups or the , like; W is an alkylene group).
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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 August 19, 2003 and granted August 7, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 19, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 19, 2025.
- 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.