Ortho-alkylation of aromatic amines
CA 2027191 A1 · Owner: Shah, Nirad N. · Inventors: Durvasula, V. Rao; Hartwell, George E.; Lee, Guo-Shuh John
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Aromatic diamines, such as toluenediamine are, alkylated in the ortho position by heating an aromatic diamine in the presence of an aluminum alloy aluminum, chloride and, optionally, zinc and then reacting with, an alkene at elevated temperatures and pressures. In one embodiment, toluenediamine, diethyltoluenediamine or mixtures thereof are heated with an aluminum alloy aluminum chloride and zinc having an average particle diameter of from 75 to 850 microns, 20 to 200 mesh U.S. Standard to form a catalyst system. This is reacted with ethene and toluenediamine to form diethyltoluenediamine. 37,851B-F
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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 9, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 9, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 9, 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.