Process for the preparation of aminomethanephosphonic acid and aminomethylphosphinic acids
CA 2089650 C · Owner: Aventis Cropscience Gmbh · Inventors: Kleiner, Hans-Jerg
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Aminomethanephosphonic acid and aminomethylphosphinic acids are interesting as biologically active compounds or as intermediates for the preparation of biologically active compounds. According to the invention such, compounds of the formula I, (see formula I) in which R1 is OH, C1-C4-alkyl or phenyl can be prepared, in a technically simple manner by reacting compounds of the formula II, (see formula II), in which R2 is H C1-C6-alkyl, benzyl, phenyl, optionally substituted by C1-C4-alkyl, -alkoxy and/or halogens and R1 is as defined above, with water, at 80 to 300°C.
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 August 7, 1991 and granted October 23, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 7, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 7, 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.