Preparation of acyl chlorides
CA 2000442 C · Owner: Basf Aktiengesellschaft · Inventors: Freudenberg, Enrique; Mayer, Kurt; Reuther, Wolfgang
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
11- , where R is C8-C30-alkyl, C8-C30-alkenyl or C8-C30-alkynyl from a carboxylic acid of the general formula II where R has the abovementioned meanings and phosgene, COC1 2 (III), in the presence of a catalyst adduct of phosgene and N,N-dialkylformamide of the general formula IV where R1 and R2 independently of one another are each C1-C3-alkyl, the reaction product I being obtained by phase separation, by a process in which II and III are used in essentially equimolar amounts and the phase containing the catalyst adduct is reused.
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 October 11, 1989 and granted September 19, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended October 11, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 11, 2011.
- 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.