Process for the preparation of carboxylic acids and esters
CA 2022100 A1 · Owner: Kiss, Laszlo · Inventors: Borlai, Oszkar; Kiss, Laszlo; Benko, Vera
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Abstract, The invention relates to the preparation of carboxylic acids and alkyl esters of the general Formula I (I), (wherein, R1 and R2 are identical and stand for lower alkyl; R3 and R4 are identical and stand for hydrogen or lower alkyl and, R5 represents hydrogen or lower alkyl) by subjecting a compound of the general Formula II (II), to ammonolysis with aqueous ammonium hydroxide in the presence of a strong inorganic base and a cupric(II)compound and, if desired, N-dialkylating the 4-amino-compound of the general Formula III, (III), thus obtained. The advantage of the process resides in the fact that inexpensive, readily available starting materials can be used and the process can be …
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 July 27, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 27, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 27, 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.