Process for the preparation of mononitro-1,2,3,4-tetrahydroanthraquinones
AssigneeProduits Chimiques Ugine Kuhlmann
InventorsSerge Y. Delavarenne, Bernard Dubreux, Pierre Tellier
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Abstract
A process is disclosed for the preparation of mononitro derivatives of 1,2,3,4-tetrahydro-anthraquinone from 1,4,4a,9a-tetrahydro-anthraquinone, in which a thermal pretreatment of the 1,4,4a,9a-tetrahydro-anthraquinone is carried out in the presence of a hydrogenation catalyst in an inert atmosphere and in the absence of oxidizing or reducing agents, the anthraquinone by-produced as well as the catalyst are separated and the mixture of 1,2,3,4-tetrahydro-9,10-anthracenediol and 1,2,3,4-tetrahydro-anthraquinone obtained is subjected to a nitration reaction.
Claims27
A process for the preparation of mononitro derivatives of 1,2,3,4-tetrahydro-anthraquinones from 1,4,4a,9a-tetrahydro-anthraquinone which comprises effecting a thermal pretreatment of the 1,4,4a,9a-tetrahydro-anthraquinone in the presence of a hydrogenation catalyst in an inert atmosphere and in the absence of oxidizing or reducing agents which leads to a mixture of anthraquinone, 1,2,3,4-tetrahydro-9,10-anthracenediol and 1,2,3,4-tetrahydro-anthraquinone, separating the anthraquinone by-product and the catalyst and subjecting the mixture of 1,2,3,4-tetrahydro-9,10-anthracenediol and 1,2,3,4-tetrahydro-anthraquinone obtained to a nitration reaction to obtain 5-nitro-1,2,3,4-tetrahydro-anthraquinone and 6-nitro-1,2,3,4-tetrahydro-anthraquinone.
Dependencies are inferred from the claim text.