Disodium 6-Hydroxy-5-[(E)-(4-Sulfonatophenyl)Diazenyl]Naphthalene-2-Sulfonate

Disodium 6-hydroxy-5- [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate, this is an organic compound. It has a wide range of uses and can play an important role in many fields.
In the dye industry, this compound is often used as a key dye component. With its unique chemical structure, it can produce a bright and stable color. After a specific process, it can closely combine with fabric fibers, giving fabrics a long-lasting bright color. Therefore, in the textile printing and dyeing process, it has become an indispensable dye raw material, helping to dye fabrics with rich and diverse colors.
It also has important uses in the field of analytical chemistry. Due to its sensitivity to specific substances or conditions, it can act as an indicator. With its color change characteristics, it can accurately indicate the chemical reaction process or the presence and content of specific substances, providing intuitive and key basis for chemical analysis, which greatly facilitates researchers and analysts to accurately analyze and determine various samples.
In addition, in some specific industrial production processes, it may also play the role of catalyst or auxiliary agent. Or it can accelerate the specific reaction process and improve production efficiency; or it can improve product performance and optimize product quality, and play a positive role in promoting industrial production quality and efficiency.
In summary, disodium 6-hydroxy-5- [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate plays an important role in the fields of dyes, analytical chemistry and some industrial production due to its unique chemical properties.

Disodium 6-hydroxy-5- [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate, this is an organic compound. Its physical properties are as follows:
Viewed, it is often powdery and has a bright orange-yellow or red color. This color is derived from the azo structure, which absorbs specific wavelengths of light, resulting in its bright color. It is widely used in the field of dyes.
In terms of solubility, it has good water solubility because it contains sulfonate groups. The sulfonate group is hydrophilic and can be combined with water molecules by ion-dipole action, so that it can be uniformly dispersed in water to form a stable solution. This characteristic can ensure uniform coloring of dyes in industrial applications such as textile printing and dyeing.
In terms of melting point, the exact melting point varies due to factors such as purity, and is roughly in a relatively high temperature range. The intermolecular forces of organic compounds, such as van der Waals force, hydrogen bonds, etc., determine the melting point. The structure of this compound causes strong intermolecular forces, which require higher temperatures to overcome, and the melting point is higher.
In terms of stability, it is relatively stable under normal conditions. In case of extreme conditions such as strong acid, strong alkali or high temperature and light, the structure may change. For example, in strong acids, azo bonds or protonation cause structural damage; high temperature, light, or luminescent chemical reactions and thermal decomposition reactions affect its properties and application effects.

The stability of the chemical properties of 6-hydroxy-5- [ (E) - (4-sulfonylphenyl) azo] naphthalene-2-sulfonate is related to many aspects. This compound contains an azo structure, and the stability of the azo group is often affected by external factors. Under light, the azo bond may be excited by absorption of light energy, causing its structure to change and affecting the overall stability. Heat is also a key factor. At high temperatures, the thermal motion of molecules intensifies, or the azo bond breaks, causing the decomposition of the compound.
Furthermore, the pH of the environment has a great influence on its stability. In a strong acid or alkali medium, the sulfonic acid group, hydroxyl group and other functional groups in the molecule may react, thereby changing the structure and stability of the compound. However, in the appropriate pH range, its structure may be relatively stable.
In addition, the sulfonic acid group in the compound is hydrophilic, which can enhance its solubility in water, and this property may also affect its stability in different solvent environments. If the interaction between the solvent and the compound is too strong or too weak, it may interfere with the intermolecular force and cause adverse effects on the stability.
Overall, the stability of disodium 6-hydroxy-5- [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate is not absolute and will vary due to factors such as light, temperature, pH and solvent. It needs to be studied in detail according to specific environmental conditions.

This is a disodium 6-hydroxy-5- [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate, which is widely used in various industries. Printing and dyeing textile industry, often used as a dye, because of its good dyeing properties, can make the fabric show rich colors, and the color fastness is quite good, the fabric dyed by it is new for a long time, and the color is not easy to fade.
In the paper industry, it is also indispensable. It can give paper a specific color, improve the aesthetics of paper, and is widely used in the manufacture of colored paper and art paper, adding color to paper products.
In addition, the ink industry is also commonly used.
Furthermore, in the paint industry, as a pigment component, it can improve the color expression and stability of the paint, so that when the paint is used in construction, furniture and other fields, it shows a lasting and beautiful effect.
All these show that disodium 6-hydroxy-5 - [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate plays an important role in many industries and is widely used.

To prepare disodium 6-hydroxy-5- [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate, the method is as follows:
Take an appropriate amount of naphthol first, place it in the reaction kettle, and slowly add sulfuric acid in a specific ratio. During this process, careful temperature control is required to make the reaction proceed within the appropriate temperature range. This is the introduction of sulfonic acid groups to obtain 6-hydroxy naphthalene-2-sulfonate intermediate product.
Then, take an appropriate amount of p-aminobenzene sulfonic acid, dissolve it in a suitable solvent, add an appropriate amount of sodium nitrite at low temperature and in a specific alkaline environment, and add an appropriate amount of acid dropwise to make p-aminobenzene sulfonic acid diazotized to form a diazonium salt solution. This step must strictly control the reaction temperature and pH to ensure the stability and activity of the diazonium salt.
After the above two reaction products are properly prepared, the solution of the intermediate product of 6-hydroxynaphthalene-2-sulfonate is slowly added to the diazonium salt solution at low temperature and constantly stirring, and the coupling reaction is carried out. In this process, the reaction process needs to be closely monitored, and the degree of reaction should be judged according to the color change of the reaction and other indicators.
After the reaction is completed, through a series of post-treatment steps, such as neutralizing the reaction solution, adjusting its pH to a suitable range, and then filtering to remove insoluble impurities, then the filtrate is concentrated and crystallized to obtain a crude product. The crude product is further recrystallized and purified, washed and filtered with ethanol or other suitable solvents for many times, and finally a pure disodium 6-hydroxy-5- [ (E) - (4-sulfophenyl) azo] naphthalene-2-sulfonate product can be obtained. Throughout the preparation process, each step requires fine operation, and strict control of factors such as temperature, pH, and the proportion of reactants is required to achieve satisfactory results.