2-Hydroxyquinoline-4-carboxylic acid

2-Hydroxyquinoline-4-carboxylic acid is an organic compound. Looking at its structure, it contains a quinoline ring, and the ring is connected with a hydroxyl group and a carboxyl group. These two give the compound unique chemical properties.
Let's talk about the hydroxyl group first, which has a certain hydrophilicity and can make the substance soluble in water. And the oxygen atom of the hydroxyl group has a lone pair of electrons, which can be used as a hydrogen bond donor or receptor to form hydrogen bonds with other molecules. This property affects its aggregation state in solution and its interaction with biological macromolecules. In chemical reactions, hydroxyl groups can be oxidized to form functional groups such as carbonyl groups; they can also participate in esterification reactions and form ester bonds with alcohols under the action of catalysts. < Br >
Looking at the carboxyl group again, the acidity is significant, and hydrogen ions can be partially ionized in water, making the solution acidic. Its acidity is conducive to the reaction with bases to form corresponding carboxylic salts. The carboxyl group is also an active functional group, which can participate in a variety of reactions, such as the reaction with amines to form amide bonds, which is crucial in the synthesis of bioactive molecules such as peptides.
As far as the quinoline ring is concerned, its conjugated structure endows the compound with certain stability. And the quinoline ring can undergo electrophilic substitution reaction. Due to the uneven distribution of electron cloud density on the ring, the activity at different positions is different, which provides the possibility to introduce other functional groups to expand the properties and uses of the compound. 2-Hydroxyquinoline-4-carboxylic acids are rich in chemical properties and have potential applications in organic synthesis, medicinal chemistry, materials science and other fields. They can be used as key intermediates for the synthesis of new functional materials and drug lead compounds.

2-Hydroxyquinoline-4-carboxylic acids are widely used in the fields of medicine, materials, and chemical synthesis.
In the field of medicine, this compound is often a key intermediate in drug development due to its unique chemical structure and biological activity. It may participate in the construction of molecular structures with specific pharmacological activities, helping to create new therapeutic drugs. For example, in the development of anti-cancer drugs, its structural properties can be used to design compounds that can precisely act on specific targets of cancer cells, which is expected to find new ways to solve cancer problems. In the development of anti-infective drugs, it can also rely on its activity to construct molecules that inhibit or kill pathogens, providing new strategies for treating infectious diseases.
In the field of materials, 2-hydroxyquinoline-4-carboxylic acid can play an important role. Because of its functional groups, it can interact with a variety of materials. For example, in optical materials, it can participate in the preparation of substances with special optical properties, or can adjust the luminescence and light absorption properties of materials, so that materials can show unique advantages in optoelectronic devices, such as Light Emitting Diodes, sensors, etc., and then promote the development of optoelectronic technology.
In chemical synthesis, this compound is an important synthetic building block. Its rich functional groups provide a variety of reaction check points for organic synthesis, chemists can use this to carry out various organic reactions, such as nucleophilic substitution, esterification, cyclization and other reactions, to construct complex and diverse organic compounds, for organic synthetic chemistry to open up a wider world, help to synthesize more novel structures and properties of organic molecules to meet the needs of different fields of special organic compounds.

To prepare 2-hydroxyquinoline-4-carboxylic acid, the method is as follows:
Usually a suitable quinoline derivative is used as the starting material. If 4-carboxyquinoline is selected, the carboxyl group is first protected with an appropriate protective group to prevent it from interfering in subsequent reactions. Alcohols can be selected, and ester groups are formed under acid catalysis for protection.
Then, the 2-position of the quinoline ring is hydroxylated. It is often reacted with a strong oxidizing agent, such as m-chloroperoxybenzoic acid, in a suitable solvent, such as dichloromethane. This process requires temperature control and is generally carried out at low temperatures, such as between 0 ° C and 5 ° C, so that the oxidant selectively attacks the 2-position to form a 2-position oxidation intermediate.
Next, the intermediate is hydrolyzed to remove the protective group and restore the carboxyl group. This hydrolysis step can be used in dilute acid or dilute alkali solution at an appropriate temperature and time. If alkali hydrolysis is used, subsequent acidification is required to obtain free 2-hydroxyquinoline-4-carboxylic acid.
Other raw materials are also used. If the quinoline ring is formed by cyclization with suitable aniline derivatives and unsaturated carbonyl compounds with carboxyl groups and suitable substituents, the target product can also be obtained through subsequent oxidation, hydrolysis and other steps. However, this process requires precise control of the reaction conditions to ensure the selectivity and yield of each step of the reaction.

I think what you are asking is about the price range of 2-hydroxyquinoline-4-carboxylic acid in the market. However, in "Tiangong Kaiwu", there is no record of the price of such chemicals, because there was no such fine chemistry at that time. Today is different from the past, the price of this chemical substance is affected by many factors.
First, the purity has a great impact. If the purity is extremely high, almost perfect, and can reach the level of scientific research, the price will be high. However, if it is only ordinary industrial grade, the purity is slightly inferior, and the price is relatively low. Second, the relationship between supply and demand is also key. If the market is in high demand and the supply is limited, the price will rise; conversely, if the supply exceeds the demand, the price may drop. Third, the production process and cost also affect the price. Complex and resource-consuming processes have high costs and high selling prices.
According to my rough investigation of the market today, this 2-hydroxyquinoline-4-carboxylic acid, if it is ordinary industrial grade, the price per kilogram may be hundreds of yuan; if it is high-purity scientific research grade, the price per gram may reach tens of yuan, or even higher. However, the market situation changes, and the price changes from time to time. It is difficult to accurately determine its range. It is necessary to constantly observe the market dynamics to know its approximation.

2-Hydroxyquinoline-4-carboxylic acid, this is a chemical substance. Its storage conditions are quite important, which is related to the quality and utility of this substance.
According to the legacy of "Tiangong Kaiwu", according to the ancient saying, it should be placed in a cool and dry place. This is the first priority, because it is in a cool and dry place, it can be protected from moisture. If it is in a humid place, moisture is easily invaded, or the properties of this substance are changed, and it loses its inherent nature.
And it needs to be kept away from fire and heat sources. Fire and heat can change chemical substances or cause dangerous reactions. 2-Hydroxyquinoline-4-carboxylic acid is heated by fire, which may decompose and burn, endangering the safety of storage.
Furthermore, it should be placed separately from other chemicals such as oxidants. Different chemical substances have different properties, and the oxidant has strong oxidizing properties. If they coexist with 2-hydroxyquinoline-4-carboxylic acid, or biochemical reactions can cause it to deteriorate, or cause accidents.
The storage place should have good ventilation. The ventilation is smooth, which can dissipate harmful gases that may be generated, maintain a suitable environment for the storage space, and keep the material in a stable state. And it should be properly sealed to prevent excessive contact with the outside air and avoid being affected by the components in the air, such as oxygen, carbon dioxide, etc. In this way, it is necessary to properly store 2-hydroxyquinoline-4-carboxylic acid, store its quality, and maintain its properties so that it can be used when needed.