Alkanethiolation process
CA 2288448 A1 · Owner: Park, Won S. · Inventors: Everly, Charles R.; Park, Won S.; Senaratne, K. Pushpananda A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A mixture formed from one or more alkyl disulfides benzene, and at least , about, 1.5 equivalents of Lewis acid catalyst is heated to form alkanethiobenzene. Reaction in a, mixture formed from excess benzene dimethyldisulfide (DMDS) and AlCl3 in which the, mole ratio of AlCl3 to DMDS was 2:1 was complete in 2 hours and afforded 98% conversion and 93% yield of thioanisole. In contrast the same reaction when , attempted, using a 1:1 mole ratio of AlCl3 to DMDS after 6 hours achieved only 66% conversion and, a thioanisole yield of only 35%. So far as is known this is the first example , of a highly efficient electrophilic aromatic substitution of the inactivated benzene ring by an …
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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 November 3, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 3, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 3, 2021.
- 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.