DE835917C - Process for the preparation of methyl and chloromethyl compounds of pyrazolanthrone-benzanthrones and their leucoesters - Google Patents

Description

Process for the preparation of methyl and chloromethyl compounds of pyrazolanthrone-benzanthrones and their leucoesters The present invention relates to chloromethylated and methylated P @ -razolanthrone benzanthrones and their I.ettkoester and a process for their production.

A product with the structural formula shown here is already on the market. This product can be produced by the condensation of pyrazolanthrone with 4-bromobenzanthrone and ring closure of the resulting condensation product can be obtained.

This product has one disadvantage, namely its tendency to be undesirable Way to turn red "when it is moistened with water, i.e. it is very sensitive to water splashes. As a result of this? Deficiency, this product is considered to be technical dye has been used very little, despite its other fastness properties are excellent.

Efforts have already been made to ensure the authenticity of the connection in question against water splashes to improve by having converted them into their dibromo and dichloro compounds. In this way, some improvements have been achieved in the fastness to water splashes, and the dihalogen compounds also have the advantage that the introduction of the halogen atoms converts the tone to a more desirable blue. however, even the dihalogen compounds do not meet the requirements of the dyeing industry with regard to the fastness to water splashes.

It has now been found that products which dab against @ \ 'water and Water splashes are real and so are the other excellent fastness properties des by condensation of 4-bromobenzanthrone and pyrazolanthrone and then Ring closure obtainable dye can be obtained by adding this dye one or two chloromethyl or methyl groups are introduced. The improvement occurs particularly in the case of dichloromethyl and dimethyl compounds, which also deliver surprising greenish blue hairdryers.

The chloromethyl and methyl compounds of 4-13rombenzanthrone and pyrazolanthrone available dye and their preparation as well as the Leucosulfuric acid esters of these compounds thus form (the aim and the object of the present invention.

The compounds in question can be represented by the following structural formula: in which X and Y are hydrogen, methyl or chloromethyl, X and Y are the same when they are not hydrogen, Y is not hydrogen when 1 is hydrogen and X is methyl when Y is hydrogen.

The exact position occupied by the substituent Y could so far cannot be determined with certainty. However, it appears that this substituent enters the 5 position; however, since this has not been precisely established, so will prefers to indicate the position of Y in the above manner.

The compounds in question can be made by various methods established «earth. For example, connections in which `X? @Lethvl and Y is hydrogen obtained by adding 9-chloromethyl-.4-bromobenzanthrone finite Py razolanthron in the presence of an acid binder such as potassium carbonate, \ atrium carbonate and the like, condensed in an inert diluent such as nitrobenzene or toluene and in the condensation product obtained in a melt of potassium or sodium hydroxide, which contains an alcohol such as methanol or ethanol and at a temperature of about loo to 15o ° is held, ring closure is effected.

Compounds in which Y is chloromethyl and X is hydrogen are obtained by treating the dye obtainable from 4-bromobenzanthrone and pyrazolanthrone with dichlorodimethyl ether in concentrated sulfuric acid or sulfuric acid monohydrate at room temperature. By increasing the temperature to 50 to 70 °, the dichloromethyl compounds are obtained, ie compounds in which X and Y are both chloromethyl.

The monochloromethyl and dichloromethyl compounds can be converted into monomethyl l- or dimethyl compounds are converted by the dyes according to the usual Procedure to be skittled.

The dimethyl compounds can also be prepared by using 4-bromobenzanthrone condensed with pyrazolanthrone in the presence of an acid binder, the condensation product Dichloromethylated as above and then ring closure in a melt of caustic alkalis is effected.

Examples of possible connections after registration are: 9-methylpyrazolanthrone-benzanthrone, x-chloromethylpyrazolanthrone-benzanthrone, x-9-dichloromethylpyrazolanthrone-benzanthrone, x-9-Dimethylpyrazolanthron-Benzanthron and the leucosulfuric acid esters of these compounds. The letter x in the nomenclature of the above compounds is intended to indicate that the Position of a chloromethyl or a methyl group not established with certainty has been.

The leuco-sulfuric acid esters are produced according to the usual process, d. H. by placing the vat dye in an anhydrous medium of pyridine, the addition product heated by pyridine and sulfur trioxide, iron, and a small amount of cuprous chloride will.

With regard to the above-mentioned chloromethylation, it is important point out that most aromatic amines are difficult or near impossible are to be chloromethylated in this way. It seems that the in question Compounds of chloromethylation accessible due to the presence of the pyrazole ring who seems to stabilize the: molecule sufficiently so that the Reaction can take place. The invention is accomplished by the following Examples further illustrate, but it is not limited to these working examples limited.

EXAMPLE 1 17.09 of the dye obtainable by condensation of 4-bromoxiizantlirone with pvrazolaiithrone and subsequent ring closure were dissolved in 6 cc of 9% sulfuric acid. At 25 ' , 20 cc l) dichlorodimethyl ether was then added. The temperature was then held at 60 ° for 15 hours. After pouring into ice water, the precipitated blue-gray solid substance was filtered off, washed neutral and dried. Healed 20.4g; Chlorine calculated 12.9%; found io, 8%. The product likely has the following formula: The colorations of this compound produced a greenish-blue tone, were fast to water splashes and also had excellent general fastness properties.

The dye is vat and then after oxidizing with air Separated by filtration, a dimethyl product is obtained which is in great abundance tones stronger than the dichloromethyl dye. This product probably has the formula shown on the left.

Example 2 35.8 g of 9-chloromethyl-4-bromobenzanthrone, 22.2 g of pyrazolanthrone, 20.0 g of powdered calcined potassium carbonate and 250 cc of nitrobenzene were heated to 2050 for 8 hours.

The solution was cooled to 25 ° and filtered. By washing with Alcohol, the filter cake was freed from nitrobenzene. The precipitate was also washed with dilute H Cl and then with water.

30.0 g of the above intermediate product were added at 50 ° to a melt of 250 g of potassium hydroxide flakes in 286 ccm of 800% ethanol. The ring closure was effected by keeping the mass at 95 ° to 100 ° for 4 hours. The melt was then poured into water, oxidized with air and filtered.

Dyeings were obtained on cotton which were somewhat more bluish than that of the dye composed of 4-bromobenzanthrone and pyrazolanthrone and which had excellent fastness properties. Example 3 20.0 g of the condensation product from Example 2 were chloromethylated as in Example i. The caustic melt was prepared as in Example 2. By this method, colorations approximately the same as those of Example i were obtained. Example 4 The chloromethylation of Example i was carried out with the same reactants, but at a temperature of 25 °. Only one chloromethyl group was introduced at this temperature. The product was then vat to convert it into the monomethyl compound according to Example i. A product was obtained which gave more bluish colorations with much better fastness to water splashes than the dye obtained from 4-bromobenzanthrone and pyrazolanthrone. However, the fastness to water splashes was not equivalent to that of the product according to Example i. Example 5 4- (Pyrazolanthronyl) -benzanthrone was chloromethylated as in Example i. In this way two chloromethyl groups were introduced, one in the 9-position and the other probably in the 5-position. After caustic melting as in Example 2, a dimethyl compound was obtained which corresponded to that of Example i. The raw material was produced by condensing 4-bromobenzanthrone with pyrazole anthrone in the presence of powdered calcined potassium carbonate and nitrobenzene at a temperature of 2o5 °.

Example 6 200 cc of pyridine were cooled to 0 ° and there were then 20 cc of chlorosulfonic acid were added within 10 minutes. The temperature was increased to 48 °, whereupon 22.5 g of the dimethyl compound of Example i, 7 g of iron (Ferrum reductum) and 0.2 g of cuprous chloride were added within 6 minutes. Of the The batch was stirred at 46 ° to 48 ° for 2 hours. 1.4 g of iron (Ferrum reductum) and stirring at the above temperature for a further 2 hours continued. The pyridine was removed under reduced pressure and the diester was salted out and secluded.

The colorations obtained with the disulfonic acid ester are gray-blue Color and excellent resistance to water stains, washing and light.

The 4-bromo-9-chloromethylbenzanthrone used in Example 2 is obtained by 4-bromobenzanthrone, which is dissolved in 96% sulfuric acid, with dichlorodimethyl ether is heated, the latter being added dropwise to the sulfuric acid solution of 4-bromobenzanthrone is added. The temperature is increased to 60 ° after the addition and 16 hours maintain. A purple-red solution is obtained, which is poured into ice water a vivid yellow precipitate separates out. The precipitate is through Filtration separated, washed acid-free and dried.

Claims (7)

PATENT CLAIMS: i. Process for the preparation of methyl and chloromethyl compounds of pyrazolanthrone-benzant'hrones and their leucoesters, characterized in that in compounds of the general formula introduced one or two chloromethyl or methyl groups and the resulting compounds of the general formula in which X and Y are hydrogen, methyl or chloromethyl, X and Y are the same if they are not hydrogen, Y is not hydrogen if X is hydrogen and X is Met.hyl if Y is hydrogen, optionally more known per se Way to be converted into the leucoester. 2. The method according to claim i for the purpose Production of 9-methylpyrazolanthrone-benzanthrone, characterized in that 9-chloromethyl-4-bromobenzanthrone with pyrazolanthrone in the presence of an acid binder, such as potassium or sodium carbonate and the like, and an inert binder such as nitrobenzene or toluene, condensed and in the obtained condensation product in one about 100 to 150 ° heated melt of potassium or sodium hydroxide and one Alcohol such as methanol or ethanol causes ring closure. 3. The method according to claim i for the purpose of producing 5 (?) - Chlormethylpyrazolanthron-Benzanthron, characterized in that that the condensation of 4-bromobenzanthrone with pyrazolanthrone and subsequent Ring closure of the product obtained with dichlorodimethyl ether in concentrated sulfuric acid or sulfuric acid monohydrate is treated at room temperature. 4. Procedure according to Claim i for the purpose of producing 5 (?), 9-dichloromethylpyrazolant'hrone-benzanthrone, characterized in that the condensation of 4-bromobenzanthrone with pyrazole anthrone and subsequent ring closure with dichlorodimethyl ether in concentrated Sulfuric acid or sulfuric acid monohydrate is treated at about 5o to 70 °. 5. Process according to claim i for the production of the 5 (?) - monomethyl or 5 (?), 9-dimethyl compound, characterized in that the monochloromethyl obtained according to claims 3 and 4 or dichloromethyl compounds are vetted by methods known per se. 6. Modification of the method according to claim 5 for the purpose of producing 5 (?), 9-Dirnethylpyrazolant'hron-Benzanthron, thereby characterized in that 4-bromobenzanthrone with pyrazolanthrone in the presence of an acid binder condensed, the condensation product obtained using dichlorodimethyl ether in concentrated sulfuric acid or sulfuric acid monohydrate at a higher temperature dichloromethylated and then ring closure is effected in a caustic alkali melt. 7. The method according to claim i to 6 for the purpose of producing the leuco sulfuric acid ester, characterized in that the dyes vat and the vat dyes obtained in an anhydrous medium made from pyridine, the addition product of pyridine and sulfur trioxide, Iron and some copper chloride are heated.