4-Pyridinecarboxaldehyde,1,2-dihydro-2-oxo-(9CI)

This substance is named 1,2-dichloro-2-oxo-4-pentenonitrile (9CI). In order to clarify its chemical structure, it is necessary to analyze the meanings of each part. "1,2-dichloro", the epichlorine atom is at the 1st and 2nd positions of the main chain; "2-oxo", refers to the carbonyl group (C = O) at the 2nd position; "4-pentene", indicates that the main chain is a pentene with five carbons, and the double bond is at the 4th position; "nitrile", that is, the -CN functional group.
According to this, the main chain of its chemical structure is a pentene with five carbon atoms. The second carbon is connected with a carbonyl group, the first and second carbons are each connected with a chlorine atom, and the fifth carbon is connected with a cyanide group (-CN). Specifically, from one end, the first carbon is connected with a chlorine atom and a methylene group (-CH =), the methylene group is connected to the second carbon, and the second carbon is connected with a chlorine atom, a carbonyl oxygen atom, and a methylene group. This second methylene group is connected to the third methylene group (-CH 2O -). The third methylene is connected to the fourth carbon-carbon double bond. The fourth carbon is connected to the fifth carbon, and the fifth carbon is connected to a cyanide group. Thus, the chemical structure of 1, 2-dichloro-2-oxo-4-pentenonitrile (9CI) is known.

9CI refers to 2-ethoxy-2-oxo-4-pentenoate ethyl ester. At the time of writing Tiangong Kaiji, modern chemical concepts and this specific compound had not yet appeared, but from the perspective of modern chemical industry, this substance has a variety of main uses.
First, in the field of organic synthesis, it is a very critical intermediate. Because of its unique molecular structure containing functional groups such as ester groups and alkenyl groups, it can participate in a variety of organic reactions. For example, in carbon-carbon bond formation reactions, alkenyl groups can be connected to other organic fragments through addition and substitution reactions to help build complex organic molecular structures, such as the synthesis of natural products or active pharmaceutical ingredients with specific structures.
Second, in the field of medicinal chemistry, using it as a starting material, with the help of subsequent functional group transformation and modification, compounds with biological activity can be prepared. Studies have shown that structural analogs show inhibitory or regulatory effects on some disease-related targets, providing possible directions for innovative drug development.
Third, in the field of materials science, through appropriate polymerization or copolymerization with other monomers, it can be introduced into the main chain or side chain of polymer materials to endow materials with special properties. Such as improving material solubility, flexibility, or introducing reactivity check points for further functional modification of materials, providing a raw material basis for the development of new functional materials.

9CI refers to 2-dioxo-2-oxo-4-nitrile, which is an organic compound. This substance has the following physical properties:
- ** Appearance and Properties **: At room temperature and pressure, it is mostly a solid or viscous liquid, and the color is colorless and transparent, or it is slightly yellow and other light colors. Due to the specific functional groups in the molecular structure, the appearance has this characteristic. This appearance characteristic has a certain impact on its physical behavior and reactivity in different environments.
- ** Melting Boiling Point **: Melting point and boiling point are determined by intermolecular forces and structures. The nitrile group (-CN) in the molecule forms a variety of intermolecular forces with other functional groups, including dipole-dipole interactions, etc., which make the molecules bond tightly, resulting in relatively high melting points and boiling points. The exact melting boiling point value varies slightly depending on the purity of the compound and the specific structure.
- ** Solubility **: In view of the strong polarity of the nitrile base in its molecular structure, it has a certain solubility in polar organic solvents such as ethanol and acetone. Due to the principle of "similar miscibility", polar solvents interact with polar functional groups, which is conducive to their dissolution; in non-polar solvents such as n-hexane, the solubility is low, because non-polar solvents interact weakly with polar functional groups.
- ** Density **: Density is related to molecular weight and molecular accumulation. The compound has a compact molecular structure and relatively concentrated mass, making it denser than water. If mixed with water, it will sink to the bottom of the water.
- ** Stability **: In the chemical structure, dioxy and oxygen-substituted functional groups give the molecular electron cloud distribution specific characteristics, and nitrile groups also participate in electron conjugation and other effects. As a whole, the chemical properties of the compound are stable under general conditions, but in case of specific chemical reagents such as strong oxidants, strong acids, and strong bases, or under extreme conditions such as high temperature and high pressure, chemical reactions will occur, because these conditions can break the original chemical bonds of molecules and promote the formation of new chemical bonds.

To prepare 1% 2,2-dioxo-2-oxo-4-parthylmethyl ether (9CI), the methods are as follows:
First, use the corresponding compound containing hydroxyl groups or halogenated groups as starting materials. If the starting material contains hydroxyl groups, the hydroxyl groups can be converted into suitable leaving groups first, such as by reacting with p-toluenesulfonyl chloride to p-toluenesulfonate, which has good activity. Then, it is reacted with a methoxy-containing nucleophile, such as sodium methoxide, the nucleophile attacks the carbon atom containing the leaving group, and through the nucleophilic substitution reaction, the leaving group leaves, thereby introducing the methoxy group. After subsequent appropriate oxidation and other steps, the target product may be 1% 2,2-dioxo-2-oxo-4-to-its methyl ether.
Second, the related reaction of olefins can be used. Select an olefin with a suitable structure, first carry out an epoxidation reaction, and use peroxy acid as a reagent to convert the olefin double bond into an epoxy structure. Afterwards, the epoxy ring interacts with methanol and appropriate catalysts under specific conditions to undergo a ring-opening reaction. The oxygen atoms in the methanol attack the carbon atoms of the epoxy ring. After the ring is opened, an intermediate containing methoxy and hydroxyl groups is formed, and then the hydroxyl group is oxidized to a carbonyl group. After reasonable regulation of the reaction conditions and steps, the target product may be prepared.
Third, start from an aldehyde or ketone. If there is an aldehyde or ketone with a suitable structure, it can be protected first, such as forming acetals or ketals to protect the carbonyl group. After that, other suitable positions in the molecule are functionalized, methoxy-related structural fragments are introduced, and then the protective group is removed to restore the carbonyl group, and then the functional group is adjusted through oxidation and other steps to achieve the purpose of preparing 1% 2,2-dioxo-2-oxo-4-to-its methyl ether. However, during the reaction process, attention should be paid to the precise control of the reaction conditions at each step, such as temperature, pH, reagent dosage, etc., to ensure that the reaction proceeds according to the expected path and improve the yield and purity of the product.

1% 2C2 + - + dicyano-2-oxo-4-phenylbenzonitrile (9CI) should pay attention to the following matters during storage and transportation:
First, this substance may be toxic and pose a potential threat to human health. Contact with it may cause skin, eye and respiratory tract irritation, or even cause more serious poisoning reactions. Therefore, when operating, be sure to take protective measures, wear protective clothing, goggles and gas masks to ensure safety.
Second, its chemical properties are relatively active and easy to react with many substances. When storing, be sure to keep away from oxidizing agents, acids, alkalis and other substances to prevent violent reactions and cause danger. And it should be stored in a cool, dry and well-ventilated place, away from direct sunlight and high temperature environment, to prevent its stability from being affected.
Third, when transporting, you must follow the relevant regulations on the transportation of hazardous chemicals. Choose suitable means of transportation, and do a good job of packaging protection to ensure that there is no risk of leakage during transportation. Transport personnel should also be familiar with emergency handling methods, and can respond quickly and properly in the event of leakage and other unexpected situations.
Fourth, the storage and transportation information of this substance should be recorded in detail, covering the time, quantity, storage conditions and transportation routes of warehousing. For future investigation, and in the event of an accident, key information can be provided in a timely manner to assist in the handling and investigation of the accident.
In short, 1% 2C2 + - + dicyano-2-oxo-4-paraben nitrile (9CI) must be stored and transported with a high degree of attention to safety, and strict compliance with various regulations and operating procedures to ensure the safety of personnel and the environment is not endangered.