Process for the production of cyclopropanenitrile derivatives
CA 2057987 C · Owner: Hanselmann, Paul · Inventors: Hanselmann, Paul
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is disclosed for the production of cyclopropanenitrile derivatives, in which a diol of the formula:, (see formula I), wherein R1 and R2 are the same or different and each is a hydrogen atom, a branched or unbranched C1-C6 alkyl group or a branched or unbranched C1-C6 alkenyl group or wherein, R1 and R2 together form a C4-C6 cycloalkyl ring is converted, with thionyl chloride to form a compound of the formula: (see formula II), The latter compound is then oxidized to form a compound of the formula:, (see formula III), The formula IV compound is subsequently converted with a cyano compound to form the desired end product of the formula:, (See formula IV), wherein R1 and R2 have the …
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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 December 18, 1991 and granted February 20, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 18, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 18, 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.