Chlorination process, alkylation of products of said process and some products thereof
CA 2122465 A1 · Owner: Tasset, Emmett L. · Inventors: Richey, W. Frank; Walters, Marlin E.; Puckett, Paul M.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Compounds having acidic protons and a molecular structure which can delocalize the electron density of the conjugate base (target compounds) are chlorinated by contacting such compounds with a perchloroalkane and aqueous base in the presence of a phase transfer catalyst which is a tetraalkylammonium hydroxide. Chlorinated products, preferably gem-dichloro compounds are produced. The, gem-dichloro compounds are useful for alkylation of aromatic compounds. For instance fluorene is chlorinated to form 9,9-dichlorofluorene which is reacted with such compounds as phenol or aniline to form such compounds as 9,9-bis(hydroxyphenyl)fluorene 9,9-bis(aminophenyl)fluorene, or …
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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 20, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 20, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 20, 2014.
- 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
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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.