4,5-Dihydroxy-3-(4-Sulfophenylazo)-2,7-Naphthalenedisulfonic Acid, Trisodium Salt

4,5-Dihydroxy-3- (4-sulfonylbenzenazo) -2,7-naphthalene disulfonate trisodium salt, looking at its name, it can be seen that this is an organic compound containing many specific groups.
Among them, the naphthalene disulfonate group provides water solubility, and the sulfonic acid group can make the compound more easily disperse and dissolve in water. The 4,5-dihydroxy group gives it a certain hydrophilicity and special reactivity. The hydroxyl group can participate in a variety of chemical reactions, such as esterification and etherification.
Furthermore, the group 3- (4-sulfonylbenzenazo) is quite critical. The structure of benzenazo has significant chromogenic properties, which may make the compound exhibit a specific color and may have applications in dyes and other fields. The sulfonyl group in the sulfobenazo further enhances its water solubility, and at the same time affects the electron cloud distribution of the benzenazo structure, thereby affecting its color and chemical properties.
Its sodium salt form, due to the presence of sodium ions, makes the compound more susceptible to ionization in aqueous solution, enhances its ionic properties, and affects its behavior in solution and interaction with other substances. This compound may play an important role in dyes, pigments, analytical reagents and other fields due to its unique chemical structure. By virtue of the characteristics of its structure, it realizes specific functions, such as color recognition of specific substances.

The physical properties of 4,5-dihydroxy-3- (4-sulfobenzene-azo) -2,7-naphthalene disulfonic acid trisodium salt are as follows:
Looking at its morphology, it is often powdery at room temperature, and the color is mostly orange yellow. The color is bright and can be distinguished. In terms of solubility, it is quite soluble in water. Due to the existence of many sulfonic acid groups in the molecular structure, such groups are hydrophilic and can form hydrogen bonds with water molecules, so that it can be better dispersed in water to form a uniform solution.
When it comes to the melting point, there is no exact and uniformly reported melting point data for this compound due to its complex structure. There are many functional groups and complex conjugated systems in the caeine structure, so when it is heated, the structure first undergoes complex changes, and there is no typical single melting point.
Its density is also difficult to have an accurate fixed value, which is greatly affected by factors such as preparation process and purity. However, roughly speaking, the density is within the relative range. Because the molecule contains structural units such as benzene ring and naphthalene ring, its density is slightly higher than that of ordinary organic small molecules.
Then talking about stability, in a dry environment at room temperature and pressure, the compound is quite stable, and the structure can remain unchanged for a long time. However, in case of extreme conditions such as high temperature, strong acid and alkali, the molecular structure may be damaged. For example, under strong acids, azo bonds or protonation reactions occur, causing their color and chemical properties to change; in strong alkali environments, hydroxyl or sulfonic acid groups may also react with bases, affecting their original properties.
Its light absorption characteristics are also unique. Due to the azo group and conjugated naphthalene ring structure, it has a significant absorption peak at a specific wavelength. In the visible region, it often appears orange-yellow, which is the result of its absorption and reflection of light at a specific wavelength. This characteristic makes it popular in the fields of dyes, analysis and detection.

4% 2C5-dihydroxy-3- (4-sulfobenzene-azo) - 2% 2C7-naphthalene disulfonate trisodium salt is used in many fields. In the printing and dyeing industry, this substance is like a highly skilled painter and can be used as a dye. With its special chemical structure, it can closely combine with fabric fibers, making the fabric show a colorful color, and the color fastness of the dye is quite good. After many washes and sun exposure, it is also difficult to fade.
In the paper industry, it is like a loyal guardian and plays the role of a dyeing aid. It can improve the uniformity of paper dyeing, make the paper more full and bright, and add a unique charm to the paper.
In the field of analytical chemistry, it is like a precise detector and is often used for the detection of metal ions. Because it can undergo color reaction with specific metal ions, by observing the change of color, it can be sensitive and accurate to determine the type and content of metal ions, providing key data support for scientific research and industrial testing.
In the field of biomedicine, it is like a discerning eye into the microscopic world and can be used as a biological stain. It is used to stain cells, tissues, etc., making it easy for researchers to clearly observe their morphology and structure under a microscope, and assisting in the in-depth development of biomedical research. It is of great significance for revealing the mysteries of life and solving disease problems.

The method of preparing 4,5-dihydroxy-3- (4-sulfobenzene-azo) -2,7-naphthalene disulfonate trisodium salt is to first take an appropriate amount of naphthalene, and introduce the sulfonic acid group at a specific position of the naphthalene through sulfonation to obtain the sulfo-containing naphthalene derivative. This step requires precise temperature control, time control and reactant ratio to achieve the expected substitution check point and degree of substitution.
Then, the obtained derivative is diazotized and coupled with a specific aniline compound under suitable conditions. During diazotization, factors such as the pH and temperature of the reaction solution must be strictly controlled to obtain stable diazonium salts. When coupling, attention should also be paid to the appropriate conditions, so that the azo bond is just at the target position to obtain the product containing the benzene azo structure.
Next, the hydroxyl group is introduced into the product. This process may require specific reagents and is achieved by substitution or other related reactions in a suitable reaction environment. The introduction of hydroxyl groups is closely related to the reaction conditions and must be carefully regulated to meet the structural requirements of the target product.
Finally, the product is reacted as a salt, and an appropriate amount of base is selected, usually sodium hydroxide, so that it fully reacts with the acidic groups in the product and converts to the trisodium salt form. After the reaction is completed, the impurities are removed by separation and purification methods, such as crystallization, filtration, washing, etc., to obtain the pure 4,5-dihydroxy-3- (4-sulfobenzene-azo) -2,7-naphthalene disulfonate trisodium salt product. The whole preparation process, the fine regulation of the reaction conditions at each step, and the strict monitoring of the intermediate products are all the keys to obtaining the target product with high purity and high yield.

4% 2C5 -dihydroxy-3- (4 -sulfobenzene azo) - 2% 2C7 -naphthalene disulfonate trisodium salt, this is a chemical substance, its use and operation are related to many safety precautions, need to be paid attention to in detail.
First, this product may be irritating. If it comes into contact with the skin, rinse with plenty of water immediately. If you still feel unwell after rinsing, be sure to seek medical attention immediately. If you come into contact with the eyes, rinse with plenty of water for several minutes urgently. If necessary, seek professional eye help without delay.
Second, when operating, be sure to do it in a well-ventilated place. Because of the specific conditions, or the evaporation of harmful gases, good ventilation can effectively reduce the concentration of harmful substances in the air and reduce the risk of inhalation. If the operating space is not well ventilated, appropriate respiratory protective equipment should be worn for safety.
Third, storage is also important. It should be stored in a dry, cool place away from fire sources and oxidants. Humid environment or deterioration, high temperature and fire sources can easily cause danger, and oxidant contact with it, or severe reaction, should be avoided.
Fourth, during use, strictly follow the established operating procedures and dosage requirements. Do not change the method and dosage without authorization to prevent accidents. Experimental or production records should be detailed and accurate for subsequent inspection and traceability.
Fifth, in the event of a leak, emergency measures need to be taken immediately. If a small amount of leakage occurs, collect it in a suitable container with a clean tool; if a large amount of leakage occurs, the scene should be isolated in time, personnel should be evacuated, and professionals should be promptly notified to deal with it. Do not dispose of it rashly.
In short, for this chemical substance, from contact, operation, storage to emergency treatment, it is necessary to treat it with caution, and strictly abide by safety regulations to ensure the safety of personnel and the environment.