Method for the preparation of 2-hydroxybenzathrone and of the substitution derivatives thereof
CA 1094060 A · Owner: Montedison S.P.A. · Inventors: Ribaldone, Giuseppe; Borsotti, Giampiero
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is disclosed for the preparation of 2-hydroxybenzanthrone and substituted derivatives thereof having the general formula:, (I), wherein:, R1 = H OH, R2, R3 = H, Cl, -OH, -OCH3, characterized in that an anthraquinone-1-diazonium salt is reacted with an olefinic compound of the formula: wherein X = CN or OCOCH3, in an alcoholic medium of a lower monovalent alcohol and in the presence of a catalytic quantity of cuprous chloride, at a temperature between 20° and 100°C and that the reaction intermediate thus obtained is reacted successively with alkali in alcoholic solution. As the diazonium salt there is used an anthraquinone -1-diazonium sulphate prepared from : …
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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 January 20, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 20, 1998.
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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.