Efficient cis-to-trans isomerization of 1,4- dihalobutene-2
CA 1297500 C · Owner: Clark, Clarence E. Jr. · Inventors: Fayter, Richard G. Jr.; Clark, Clarence E. Jr.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to an efficient cis-to-trans isomerization of 1,4-dihalobutene-2 by means of a thiol or hydroyen bromide or hydrogen chloride catalyzed reaction. Said isomerization provides a high trans content greater than 90% which in turn is eminently suitable for condensation with malonic esters to provide excellent yields of dimethyl 2vinylcyclopropane-1, 1-dicarboxylate with greater than 95% purity and with substantial elimination of 3,4-dichlorobutene-1.
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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
- Granted March 17, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended March 17, 2009.
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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.