Method for the continuous production of tetra-substituted ureas
CA 2489408 A1 · Owner: Busch, Ralph · Inventors: Weber, Theodor; Rohde, Thorsten; Busch, Ralph
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method for producing tetra-substituted ureas by reacting the corresponding amines with phosgene in the presence of an aqueous inorganic base at a temperature ranging of from 0 to 150 ~C. According to the inventive method, the corresponding amine the phosgene and the aqueous , inorganic base are on average continuously fed to the reactor a two-phase , system is formed in the reactor by selecting the tetra-substituted ureas to be produced, by selecting the quantitative ratio of the substances and substance mixtures to be added, by selecting the temperature during reaction and optionally by adding an organic solvent that is not completely miscible with water, …
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 3, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 3, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 3, 2025.
- 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.