Process of producing 1,3,3-trimethyl-5-oxo-cyclohexane-carbonitrile
CA 2032667 C · Owner: Schmitt, Hermann · Inventors: Huthmacher, Klaus; Schmitt, Hermann
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The addition of hydrogen cyanide to isophorone for the production of 1,3,3-trimethyl-5-oxo-carbonitrile is successful when using lithium hydroxide in an amount from 0.005 to 5 mole % at 100 to 160°C with a high yield and with a substantially higher space time yield than was possible with the use of other alkaline reacting alkali compounds.
Read the whole patent
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 19, 1990 and granted September 17, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 19, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 19, 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.
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.