Process for the preparation of fluorobenzenes and fluorotoluenes
CA 2070386 A1 · Owner: Leupold, Ernst I. · Inventors: Sistig, Frank P.; Litterer, Heinz; Leupold, Ernst I.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process for the preparation of fluorobenzenes and fluorotoluenes, Abstract, A process for the preparation of fluorobenzenes and fluorotoluenes of the formula (I), in which X is H or a methyl group, R1, R2 and R3 are, independently of each other, at least one of the radicals H, F Cl and C1-C3-, alkyl, at least one of these radicals being fluorine and, S1 and S2 are, independently of each other H and/or, radicals which reduce the electron density at the benzene nucleus, but preferably H, characterized in that benzaldehydes of the formula (II) in which R1 R2, R3, S1 and S2, have the meaning given above are reacted of a catalyst, activated by treatment with hydrogen comprising at least, one …
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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 18, 1990. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 18, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 18, 2012.
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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.