Process for the production of pyranthrones or flavanthrones
AssigneeCiba-Geigy Corporation
InventorsJurgen Markert, Hans Morawietz
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Abstract
A process for the production of pyranthrones or flavanthrones which comprises reacting substituted or unsubstituted 2,2'-dialkyl-1,1'-dianthraquinonyls or 2,2'-diacylamino-1,1'-dianthraquinonyls respectively in a two-phase system of aqueous organic solvents using quaternary ammonium or phosphonium compounds as catalysts.
Claims10
A process for the production of pyranthrones or flavanthrones (II), which comprises reacting substituted or unsubstituted 2,2'-dialkyl-1,1'-dianthraquinoyls or 2,2'-diacyl-amino-1,1'-dianthraquinoyls (I) respectively in a two-phase system of a mixture of water and a water-immiscible organic solvent or solvent mixture in the presence of 0.01 to 40 mole percent, based on the amount of the compound (I), of quaternary ammonium or phosphonium compounds as catalysts, with good stirring, in neutral to alkaline pH range between 80.degree. and 130.degree. C.
Dependencies are inferred from the claim text.