Benzofurans and a novel method of preparation
CA 1291487 C · Owner: Welter, Thomas R. · Inventors: Welter, Thomas R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
There are disclosed novel benzofurans having the following structural formula:, wherein R is alkenyl of 1 to 6 carbon atoms or aryl of from 6 to 10 carbon atoms; R1 is H, alkali metal, or alkyl of 1 to 4 carbon atoms; and R2 is alkyl or alkoxy of from 1 to 5 carbon atoms hydrogen, amino or dialkylamino, nitro sulfonyl, alkyl or aryl thioether or halo. Also disclosed is a novel process of making the benzofurans comprising, the step of cyclizing an o-(2-carboxyvinyl)phenyl unsaturated alkyl ether in the presence of a base selected from the group consisting of KOH NaOH, LiOH, dimsyl sodium, lithium diisopropylamide potassium text-butoxide, and mixtures thereof at, room temperature. The …
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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
- Granted October 29, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended October 29, 2008.
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Timeline
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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.