Patent GB-587006-A (GB)
Title: Process for the manufacture of aminophthaloylacridones
IPC: C09B5/36
Filed: 1944-07-31
Abstract: 6-Amino-31 : 41-phthaloylacridone is prepared by treating a 7-halogeno-6-amino-31 : 41-phthaloylacridone with a reducing agent followed by treatment with an oxidizing agent and isolating the product by filtration.  The reducing treatment is preferably a mild one such as in an aqueous solution containing sodium hydrosulphite alone, or in combination with sodium carbonate or sodium phosphate. Other reducing agents specified include ferrous sulphate and ammonia, and stannous chloride and hydrochloric acid.  The reduction is carried out at about 50 DEG  C.  The oxidizing step is carried out by exposure to air or to an oxidizing agent such as m-nitrobenzene sulphonic acid.  The 7 halogeno - 6 - amino - 31 : 41 - phthaloylacridones which are used as starting materials may carry additional substituents such as alkyl, aryl, alkoxy, aryloxy, halogeno, alkanesulphonyl, aralkanesulphonyl, benzenesulphonyl, trifluoromethyl and alkylsulphonamido groups.  Starting materials mentioned include the 7 - chloro - 6 - amino-, 7 - bromo - 6 - amino-, 7-bromo-6-amino-2-dimethylaminosulphonyl-, 7 - bromo - 6 - amino - 1 - methoxy-, 7 - bromo - 1 - nitro - 6 - amino-, 10 : 12 - dichloro - 7 - bromo - 6 - amino- and 7-bromo-6-amino-10-methanesulphonyl-31 : 41-phthaloylacridones.  In examples: (1) 7-Chloro-6-amino-31 : 41-phthaloylacridone is treated in aqueous solution with sodium carbonate and sodium hydrosulphite at 50-60 DEG  C. for one hour followed by treatment with sodium-m-nitrobenzene sulphonate, and filtration of the product. The 7-bromo-compound may be used instead of the 7-chloro-compound to yield the same product.  (2) As in example (1), but using the 2-dimethylaminosulphonyl-compound to produce the corresponding 2-substituted product.  (3) As in example (1), but using the 1-methoxy-substituted compound.  (4) As in example (1), but using the 1-nitro-substituted compound.  (5) As in example (1), but using the 10 : 12-dichloro-substituted compound.  (6) 7-Bromo-6-amino-31 : 41-phthaloylacridone is reduced with ferrous sulphate and ammonia in aqueous solution and oxidized with air by well stirring in aqueous suspension to give the same product as example (1).  (7) 7-Bromo-6-amino-31 : 41-phthaloylacridone is treated with sodium hydrosulphite in aqueous suspension and then oxidized with nitrobenzene to give the same product as example (1).  (8) 7-Bromo-6-amino-31 : 41-phthaloylacridone is reduced with an aqueous solution of sodium phosphate and sodium hydrosulphite and oxidized with sodium m-nitrobenzenesulphonate to give the same product as example (1). (9) 7-Bromo-6-amino-10-methanesulphonyl-31 : 41-phthaloylacridone, obtained according to example (1) of Specification 586,999, is reduced in aqueous solution with sodium hydrosulphite and sodium carbonate and oxidized with sodium m-nitrobenzenesulphonate to the corresponding 10 - methanesulphonyl - compound.  (10 7 - Bromo - 6 - amino - 31 : 41 - phthaloyl acridone is reduced with stannous chloride and hydrochloric acid and oxidized as in example (1) to give the same product.  (11) 7-Bromo-6-amino-31 : 41-phthaloylacridone is treated in chlorobenzene solution with a paste of nickel, kieselguhr and dimethylaniline and treated with hydrogen.  The product is filtered, dried in air and extracted with hot dichlorobenzene to give the same product as example (1).  The 7-halogeno - 6 - amino -31 : 41 - phthaloylacridones which are used as starting materials are prepared by condensation of a 1-amino-2 : 4-dihalogeno-anthraquinone with an anthranilic acid and cyclising the condensation product.  This reaction is stated to proceed very smoothly.  7-Chloro-6-amino-31 : 41-phthaloylacridone is made by condensing 2-chloro-4-bromo-1-amino-anthraquinone with anthranilic acid in the presence of copper acetate in phenol solution to give 2-chloro-4-(o-carboxyanilino)-1-amino-anthraquinone which is cyclised with chlorosulphonic acid.  The 7-bromo-compound may be similarly prepared.  7-Bromo-6-amino-2-dimethylaminosulphonyl-31 : 41-phthaloylacridone is similarly prepared using 2 : 4-dibromo-1-amino-6-dimethylaminosulphonylanthraquinone, which is itself made by treating 1-nitro-anthraquinone-6-sulphonyl chloride with dimethylamine, reducing the 1-nitro-6-dimethylamino compound to the 1-amino - 6 - dimethylamino compound and brominating. 7-Bromo-6-amino-1-methoxy-31 : 41-phthaloylacridone is made by brominating 1-amino-5-methoxyanthraquinone, condensing with anthranilic acid and cyclising with chlorosulphonic acid.  7 - Bromo - 1 - nitro - 6 - amino - 31 : 41-phthaloylacridone is made by brominating 5-nitro-1-amino - anthraquinone condensing with anthranilic acid and cyclising.  10 : 12 - Dichloro - 7 - bromo - 6 - amino - 31 : 41 - phthaloylacridone is made by cyclising 2-bromo-1-amino-4-(21 : 41-dichloro-61-carboxyanilino) anthraquinone with chlorosulphonic acid.