Dioxane adduct of 2-hydroxynaphthalene-6-carboxylic acid and process for the preparation thereof
CA 1332840 C · Owner: Von Plessen, Helmold · Inventors: Von Plessen, Helmold; Rittner, Siegbert
Overview
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Open the CIPO recordAbstract From the Canadian patent
The invention relates to the dioxane adduct of 2hyroxynaphthalene-6-carboxylic acid which adduct comprises 1 mol of 1,4-dioxane and about 2 mol of 2-hydroxynaphthalene-6carboxylic acid per mol. The invention further relates to a process for the preparation of this adduct wherein the 2-, hydroxynaphthalene-6-carboxylic acid is dissolved in dioxane or a mixture thereof with water or with an organic solvent and then allowed to crystallize. The adduct is useful for an easy isolation and purification of 2-hydroxynaphthalene-6-carboxylic acid from the reaction products of the Kolbe-Schmitt reaction. The adduct is of special significance for the production of very pure …
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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 November 1, 1994. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended November 1, 2011.
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