DE568311C - Process for the preparation of oxyanthraquinone derivatives - Google Patents

Description

Process for the preparation of oxyanthraquinone derivatives The invention relates to the production of oxyanthraquinone derivatives. It is known to be p-chlorophenol with phthalic anhydride in the presence of sulfuric acid and boric acid for the purpose of recovery to condense of quinizarin. Besides p-chlorophenol, the condensation was also with o-chlorophenol and substituted o-chlorophenols, and it was formed other oxyanthraquinone derivatives.

It has now been found that halogenated phthalic acids can also be condensed with halogenated phenols in the presence of sulfuric acid and boric acid to give oxyanthraquinone derivatives. The present process has the advantage that oxyanthraquinone derivatives are obtained which have substituents in both benzene rings of the anthraquinone nucleus. It is known (see patent specification 172 IO5) to condense hydroquinone with chlorinated phthalic anhydrides in sulfuric acid with or without the addition of boric acid to give chlorine-substituted quinizarines. In this case, however, there must not be more than one halogen atom in o-position to the carboxyl groups of the phthalic anhydride, whereas in the present process, for example, 3.6-dichlorophthalic anhydride can be used, which therefore has two halogen atoms in o-position to the carboxyl groups. In general, the present process gives better yields. As; Starting materials are on the one hand. halogenated derivatives of phthalic anhydride, for example q.-chloro and 3. q.-dichlorophthalic anhydride and the corresponding phthalic acids or their salts are used. Chlorinated phenols in particular are used as halogenated phenols.

The condensation can be achieved by heating with sulfuric acid and boric acid but instead of sulfuric acid you can also use oleum and instead of boric acid, compounds of boric acid, for example borax.

The use of phthalic acids or their salts instead of the anhydrides offers an advantage in that it is not necessary to manufacture it of halogenated phthalic anhydride derivatives first in the form of halogenated Phthalic acids or their salts obtained products before carrying out the condensation to convert into the anhydrides.

Briefly, the invention consists in the fact that halogenated phthalic acids, their salts or anhydrides condensed in sulfuric acid with halogenated phenols will. The condensation is expediently carried out by sulfuric acid with boric acid or the like. causes.

Here, a-position chlorine atoms are in the anthraquinone derivatives obtained wholly or partially hydrolyzed and replaced by hydroxyl groups. the the following examples illustrate the invention; without it being restricted to it. The parts are parts by weight.

Example i 4.95 parts of p-chlorophenol are stirred with 20 parts of 23% strength oleum, the temperature being kept below 17-5'C. The mixture is then heated to 125 ° C. for 3 hours, whereupon 8.34 parts of 4-chlorophthalic anhydride are added and then 10 parts of 23% strength oleum and 3.3 parts of boric acid. The temperature is then increased in 3 hours to 1 7 5 ° C, through obtain 4 hours at I73 ° C, then 3 hours at 195 ° C is increased and therethrough get 12 hours at this temperature. The mass is cooled, poured into water, boiled and filtered. The product is a light, red-brown powder that contains 13.5% chlorine. (The theoretical value of 6-chloroquinizarin is i2.9oj0.) Example? 52 parts of 20% oleum and 13 parts of p-chlorophenol are gradually mixed together. The temperature is increased to 130 ° C. and maintained at this temperature for one hour. Another 5z parts of oleum are then added together with 24 parts of acid potassium 4-chlorophthalate and 9 parts of boric acid. The temperature is increased to 180 ° C. in 1/2 hour and maintained at this temperature for 41/2 hours. The product is isolated by pouring it into water. .

Example 3 12 parts of p-chlorophenol and 48 parts of 2o0joiges oleum are used heated to 25 ° C until a sample is soluble in saline. 25 parts of 3 # 4-dichlorophthalic anhydride, 30 parts of sulfuric acid monohydrate and 10 parts of boric acid are then added. The temperature is raised to 195 ° C and maintained for 25 hours. The product is isolated in the usual manner and appears to consist of 5 # 6-dichloroquinizarine.

Example 4 This is similar to Example 2 except that the acidic potassium chlorophthalate with an equivalent amount of acidic potassium 3 # 4 dichlorophthalate is replaced.

Example 8 parts of 2 # 4-dichlorophenol and 3o parts of 23% strength oleum are used Heated to 125 ° C for 3 hours. 12 parts of 4 # 5-dichlorophthalic anhydride, 20 parts of 2; o; oily oleum and 5 parts of boric acid are added. The temperature will 4 hours at 175 °. C obtained, whereupon it is heated to r95 ° for 15 hours C heated. The product is isolated as usual and appears mainly from 2 # 6 # 7-Trichlorquinizarin insist.

Example 6 This is similar to Example 3 except that 4 # 5-dichlorophthalic anhydride is used. The product consists of 6 # 7 dichloroquinizarin.

Example 7 10 parts of o-chlorophenol and 30 parts of sulfuric acid monohydrate are stirred together and 15 parts of 4 # 5-dichlorophthalic acid and another 3o parts Sulfuric acid monohydrate and 8 parts of borax were added. The temperature will be on Increased i85 ° C and the mass was kept at this temperature for about 15 hours. That Product contains 27% chlorine and appears to be essentially a mixture of di- and trichlorodioxyanthraquinone. The chlorine content of the end product can changed to a certain extent by changing the condensation conditions will.

Example 8 24 parts of p-chlorophenol are made into a mixture of 12 parts 23% oleum and 8 parts of go% sulfuric acid -introduced. After getting the crowd Has heated to 125 ° C for 2 hours, 5 parts of 3 # 6-dichlorophthalic anhydride and furthermore i2 parts of 23% strength oleum and 2 parts of borax are added. The temperature is then heated to 175 ° C and obtained for 3 hours, followed by 9 hours stirred through at 95 ° C.

It should be noted that especially in Example 4 the surprising The result is that while one chlorine atom is in one benzene ring of the molecule is hydrolyzed, the chlorine atom in the other benzene ring does not appear to be hydrolyzed will.

Claims (1)

PATENT CLAIM: Process for the production of oxyanthraquinone derivatives, characterized in that halogenated phthalic acids, their salts or anhydrides condensed with halogenated phenols in the presence of sulfuric acid with boric acid or the like.