DE599914C - Process for the production of Kuepen dyes of the flavanthrone series - Google Patents

Description

Process for the production of vat dyes of the flavanthrone series In the patent 599,246 it was shown that vat dyes of the flavanthrone series and dye intermediates obtained when 9-oximes of the anthraquinone series, the contain halogen in the i-position, or those obtained from them by alkylation, arylation or acylation available derivatives treated with metals. One can use the dye intermediates also obtained in other ways, e.g. B. by 9-oximes of the anthraquinone series, their Alkyl, aryl or acyl derivatives which contain an amino group in the i-position, diazotized and the diazonium compounds obtained by methods known per se converted into the corresponding dianthraquinonyl derivatives.

It has now been found that the z. B. by the method of said Patent preparable dye intermediates in vat dyes of the flavanthrone series pass if they are heated by themselves or in the presence of diluents or treated with condensing agents and optionally those formed Products, e.g. B. if the vat dyes arise in the form of the leuco compounds, subjected to post-treatment with oxidizing agents. It can be assumed that at the formation of the vat dyes of the flavanthrone series according to the method of Patent 599,246 from the i-position halogen containing 9-oximes of the anthraquinone series or the derivatives obtainable from them by alkylation, arylation or acylation initially with elimination of the halogen atoms in the i-position, derivatives des i, i'-dianthraquinonyls are formed. The transition z. B. the methylation product of i-chloroanthraquinone-9-cisoxime (I) in flavanthrone (IV) would be accordingly z. B. formulated as follows: For formulas see overleaf.

The elemental analyzes of the dye intermediates obtainable by the process of patent 599 246 speak for the correctness of this view. So lets z. B. the analysis of the described in Example 4 of the patent 599 246, crystallizing from acetone in coarse, almost colorless prisms or those obtainable according to Example 3, from chlorobenzene in pale yellowish; matted needle-separating compound for these products to include compositions according to the forms designated II or III. Both bodies pass into flavanthrone (IV) or leukoflavanthrone when heated by themselves or in a suitable diluent such as denophenone or a-nitronaphthalene, or when melted with alcoholic potash. Other agents that cause the formation of dyes or leuco dyes are, for. B. called: cold and warm concentrated sulfuric acid, cold and warm alkaline sodium hydrosulfite solution, phosphorus oxychloride, heavy metal salts such as copper chloride, zinc chloride or sulfate, iron chloride, etc., which may advantageously be used in the presence of suitable diluents. It is also possible, through an appropriate choice of the condensing agent, to combine the introduction of substituents with the formation of the dye. For example, when iron chloride is used as a condensing agent, chlorine-containing dyes may be obtained. In those cases in which the dyes are not readily obtained in pure form, they can be used by the usual methods, for. B. by recrystallization, Umküpen or sublimation, clean.

Example i That according to example 3 of patent 599,246 is reheated filtering off the flavanthrone crystallizing out of the cooling reaction mixture Product, which probably corresponds to formula III, gradually appears in vacuo about 500 °. The resulting flavanthrone sublimes in the form of fine golden yellow Needles.

EXAMPLE e 10 parts of the compound (formula II) described in Example 4 of Patent 599: 246 are heated to boiling with 160 parts of a-nitronaphthalene until the dye formation has ended. When the melt cools down, the flavanthrone separates out in beautiful yellow needles just below the boiling point of a-nitronaphthalene. B. can separate from the liquid after adding nitrobenzene to the reaction mixture. The intermediates described in Examples 3 and 5 of patent 5991246 can be converted into flavanthrone in the same way. The reaction can also be carried out at much lower temperatures, e.g. B. at 17o to igo °, but must then continue heating for a long time. Appropriate condensation agents are then used to promote dye formation, e.g. B. heavy metal salts, phosphorus oxychloride and the like. To the reaction mass.

Example 3 In a mixture of 100 parts of potassium hydroxide heated to 1300 and 100 parts of ethyl alcohol are carried 1o parts of that used in Example i or 2 Starting material and keeps the melt on the same for about 1 hour Temperature. After diluting with water one obtains a. blue vat from the flavanthron by oxidation, e.g. B. with air can be obtained.

Example q.

The starting material used in example i is finely divided brought, e.g. B. by dissolving in pyridine and precipitating with water. From the thus obtained, Paste washed out with water is obtained by treatment with alkaline reducing agents, z. B. with alkaline sodium hydrosulfite solution, slowly in the cold, when warming faster a blue vat from which flavanthron can be separated in the usual way or which can also be used directly for dyeing.

Example s 1o parts of the starting material used in Example 1 96 ° / aige sulfuric acid are entered in 180 parts at room temperature. To When the dye formation has ended, the olive-green solution is poured into water. The eliminated Flavanthron is more or less olive colored due to a small amount of it Leuco compound formed by a side reaction. Through treatment the suspension with oxidizing agents takes the yellow color of the pure flavanthrone at.

B: example 6 Those obtainable according to example 6 of patent 599,246 are heated Products which correspond to formulas II and III, but in each case in the 3 and 3 'position still contain two methyl groups, with alcoholic potash in that given in Example 3 Manner, whereby 3,3'-dimethylflavanthrone is obtained.

If that of the formula III is treated analogously, in the 3- and 3'-positions dimethylated product with sulfuric acid, as described in example e, is obtained one also has 3,3'-dimethylflavanthrone.

Example ? Those obtainable according to Example 7 of Patent 599: 246 are heated Products that are likely to be mixtures of dichloro derivatives of the formulas II or III are corresponding compounds, with alcoholic potash in the example 3 specified way. A mixture of dichloro flavanthrones is obtained.

If the mixture of dichloro derivatives of the formula III is treated Product with sulfuric acid, as described in Example s, is also obtained a mixture of dichloro flavanthrones.

Claims (1)

PATENT CLAIM: Process for the preparation of vat dyes of the flavanthrone series, characterized in that dye intermediates of the general formula are used heated by themselves or in the presence of diluents or treated with condensing agents.