JPS6045868B2 - Manufacturing method for anthraquinone intermediates - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing anthraquinone intermediates that are particularly useful in the dye industry.

More specifically, the present invention relates to dibromination of 1-aminoanthraquinone in the presence of an aliphatic dicarboxylic acid or an aromatic mono- or dicarboxylic acid in at least 50% (by weight) sulfuric acid or at most 10% (by weight) fuming sulfuric acid. , 1-amino-2,4-dibromoanthraquinone.

Conventionally, as a method for producing 1-amino-2,4-dibromoanthraquinone, 1-aminoanthraquinone-2-
Method for dibrominating sulfonic acids in aqueous solvents (J, C
, S1939, page 816, USP 2169196),
Method for dibrominating 1-aminoanthraquinone in an inert organic solvent (Ber, Niray 2165, BP123977
8) A method of dissolving 1-aminoanthraquinone in sulfuric acid, discharging it into water to atomize it, and converting it to dibromination in the aqueous dispersion (PB Report No., 86139, page 6, 9U)
llmannsEneyclopad'lederte
chnischenchemie4AuflBand7
9, Section 59) is known.

However, these methods have various problems when they are actually intended to be industrialized, and cannot be said to be advantageous methods.

As an improved version of these methods, Japanese Patent Application Laid-Open No. 53-133
No. 23 describes a method for dibromination in concentrated sulfuric acid, especially 85-98% J sulfuric acid. This method is
It is notable for its high productivity due to the use of highly concentrated sulfuric acid, the generation of little waste acid, and the ability to obtain 1-amino-2,4-dibromoanthraquinone of excellent quality. The present inventors conducted intensive studies to obtain 1-amino-2,4-dibromoanthraquinone of even higher quality than the above method, and found that during the dibromination reaction, aliphatic dicarboxylic acid or aromatic mono- or dibromated It has been found that 1-amino-2,4-dibromoanthraquinone of excellent quality and free of by-products can be obtained in high yield by the presence of a chemical reaction. That is,
According to the method of the present invention, the quality of 1-amino-2,4-dibromoanthraquinone is improved because the by-product of trace amounts of blue impurities produced during bromination in conventional methods is improved, and as a result, the quality of 1-amino-2,4-dibromoanthraquinone is improved. The quality of 1-amino-2-bromo-4-hydroxyanthraquinone produced is significantly improved. Therefore, the disperse dye obtained using this as a raw material gives a vivid dyed product. In the present invention, examples of aliphatic dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, and mixtures thereof.

Aromatic mono- or dicarboxylic acids include, for example, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid and mixtures thereof. The amount of these dicarboxylic acids added is usually 0.0 to 1-aminoanthraquinone.
5-1.5 molar ratio, preferably 0.1-1.4 molar ratio. In the present invention, the dipromylation reaction is carried out by 50%
It is carried out in sulfuric acid of 10% or less or fuming sulfuric acid of 10% or less. In consideration of consistency with the next hydrolysis step, concentrated sulfuric acid of 85% or more or fuming sulfuric acid of 10% or less is preferably used.
As the brominating agent, bromine is preferably used, and the amount used is 1.0-3 to 1-aminoanthraquinone.
．． A molar ratio of 0 is good, and using a molar ratio of 3 or more is economically disadvantageous.

The dipromylation reaction usually proceeds at a temperature of 50-150°C, but preferably at a temperature of 60-130°C.

The 1-amino-2,4-dibromoanthraquinone thus obtained is extremely valuable as a dye intermediate, and is usually converted into 1-amino-2-
After being made into bromo-4-hydroxyanthraquinone, it is used as a raw material for a disperse dye, and the resulting dye has significantly improved sharpness compared to those obtained by conventional methods. Next, the present invention will be explained with reference to Examples.

In the text, parts and % mean parts by weight and % by weight. Example 1 20 parts of 1-aminoanthraquinone and 12 parts of succinic acid are added to 1 (1) part of 94% sulfuric acid, and the temperature is raised to 110°C while stirring.

At the same temperature, 28.7 parts of bromine was added dropwise over 5 hours. After further incubating at the same temperature for 5 hours, cool to room temperature,
．． Drain contents into 5(1) parts containing 6 parts water. The precipitated crystals were filtered, washed, and dried to obtain 34.7 parts of 1-amino-2,4-dibromoanthraquinone (purity 97.0%,
A yield of 98.5%) was obtained. For comparison, the purity of 1-amino-2,4-dibromoanthraquinone obtained by the same reaction without using succinic acid was 94.
The yield was 94.2%. These 1-
The yield of 1-amino-2-bromo-4-hydroxyanthraquinone obtained by hydrolyzing amino-2,4-dibromo-anthraquinone as a raw material was higher when the raw material was added with succinic acid. .

Example 2 1 part of 1-aminoanthraquinone and 5 parts of benzoic acid are added to 1 part of 100% sulfuric acid, and the temperature is raised to 120°C while stirring.

At the same temperature, 28.7 parts of bromine was added dropwise over 5 hours. After further incubating at the same temperature for 5 hours, it was cooled to room temperature and subjected to the same finishing treatment as in Example 1. Yield: 97.
2%). For comparison, 1-amino-2, which was obtained by the same reaction without using benzoic acid.
The purity of 4-dibromoanthraquinone was 93.5%, and the yield was 93.4%. These 1-amino-2
, 4-Dibromo anthraquinone obtained by hydrolysis as a raw material, the 1-amino-2-bromo-4-hydroxyanthraquinone obtained by adding benzoic acid as a raw material has higher purity and yield. Ta.

Claims (1)

[Claims] 1 1-Aminoanthraquinone is dibrominated in the presence of an aliphatic dicarboxylic acid or an aromatic mono- or dicarboxylic acid in at least 50% (by weight) sulfuric acid or at most 10% (by weight) fuming sulfuric acid to produce 1-amino- 2. A method for producing an anthraquinone intermediate, characterized in that it is 4-dibromoanthraquinone.