Process for the preparation of alcanesulfonic acids
CA 2124536 C · Owner: Ollivier, Jean · Inventors: Ollivier, Jean; Lacombe, Sylvie
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a process for preparing alkanesulfonic acids by photooxidation of dialkyl disulfides. The operation is carried out in solution in an alcohol in the presence of oxygen and a light source emitting between 200 and 320 nm. This process produces excellent yields of alkanesulfonic acids.
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 May 27, 1994 and granted December 1, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 27, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 27, 2016.
- 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.