Process for the preparation of sulfonyl isocyanates
CA 2061733 A1 · Owner: Schlegel, Guenter · Inventors: Berger, Harald; Lachhein, Stephen; Schlegel, Guenter
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 sulfonyl isocyanates The invention relates to an improved process for the preparation of a compound of the formula R1-X-SO2-NCO in which, X is O or NR2, R1 is alkylsulfonyl or phenyl which is optionally substituted by Hal, alkyl and/or alkoxy and, R2 is alkyl, by reacting, R2XH with ClSO2NCO to give the compound R1XCONHSO2Cl followed by a rearrangment reaction, which comprises carrying out the process continuously in the presence or absence of an inert solvent.
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 February 24, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 24, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 24, 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
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.