3,4-dichloro-5-fluoro-pyridine

3,4-Dihydro-5-vinylpyrimidine, although this substance is not detailed in "Tiangong Kaiwu", it is deduced from various ancient books and ancient common sense. Its uses may have the following ends.
First, it is used in the way of medical preparation, or it can be a key material for medicinal synthesis. Ancient physicians, who studied pharmacology, often used various rare materials to refine medicine to help the world. Or based on this substance, after complex processing methods, combined with other medicines, made a good prescription for treating diseases and treating diseases. Looking at ancient medical texts, many of them were based on unique organic materials to reconcile medicinal properties and heal those who were suffering from diseases. For example, the methods of drug synthesis recorded in the Compendium of Materia Medica may be circumstantial evidence for their medicinal uses.
Second, it may have special effects in ancient chemical processes such as alchemy and alchemy. Ancient alchemists were obsessed with alchemy and alchemy, hoping to live forever and turn stones into gold. The special chemical properties of 3,4-dihydro-5-vinylpyrimidine may cause unique chemical reactions during the refining process, changing the properties of alchemy and alchemy. Such as the various materials and reactions in alchemy recorded in Ge Hong's "Baopuzi", which can be used as evidence for its chemical process.
Third, it can be used as a special dye or auxiliary in the field of fabric dyeing and pigment modulation. The ancient dyeing and weaving process is developed, and the pursuit of fabrics with bright colors and lasting. Or use this substance as a mordant to help the dye adhere better to the fabric, making the color brighter and the fastness better. Looking at the dyeing method recorded in "Kaogong Ji", it may also be a speculative basis for its use in the field of dyeing and weaving pigments.
Fourth, in the preparation of fragrances, it may have unique power. The ancients are very fragrant, whether it is smoked clothes, smoked rooms, or used in medicine, fragrances are indispensable. 3,4-Dihydro-5-vinyl pyrimidine may have a unique smell, or can adjust the fragrance of fragrances, making the aroma richer and more layered. In the ancient incense spectrum, there are many records of special organic materials mixed with strange fragrances, which can be used as a speculative reference for its use in fragrances.

The synthesis method of 3,4-difluoro-5-methoxypyridine is often related to the delicate multi-step organic synthesis technology.
First, it can be started from a suitable pyridine derivative. First, fluorine atoms are introduced precisely by halogenation reaction. In an appropriate reaction system, a halogenating agent, such as a fluorine-containing halogenating agent, is selected, and at a suitable temperature and in the presence of a catalyst, a specific position of the pyridine ring is halogenated to form a fluorine-containing pyridine intermediate. This step requires fine regulation of the reaction conditions to ensure that the position and quantity of fluorine atoms introduced are accurate.
Then, the methoxylation reaction is carried out. The above fluorine-containing pyridine intermediates are reacted with methoxylating reagents, such as sodium methoxide, in a suitable solvent, at the appropriate temperature and reaction time. This process requires attention to the progress of the reaction to ensure that the methoxy group is successfully connected to the target position to form 3,4-difluoro-5-methoxy pyridine.
In addition, there are other synthesis paths. The basic skeleton of the pyridine ring can be constructed first, and then fluorine atoms and methoxy groups can be introduced in sequence. For example, the pyridine ring is constructed by cyclization reaction with specific organic small molecules as raw materials. Then, the pyridine ring is gradually modified in the order of halogenation and methoxylation. The key to this path lies in the control of the cyclization reaction conditions to ensure that the structure of the pyridine ring is formed correctly, and the subsequent halogenation and methoxylation reactions can proceed smoothly.
In addition, during the synthesis process, the separation and purification of the reaction intermediate and the product are also crucial. Methods such as column chromatography and recrystallization are often used to obtain high-purity 3,4-difluoro-5-methoxy pyridine, which meets the strict requirements of product purity in different application scenarios. Each step of the reaction requires fine operation and consideration of many factors of the reaction conditions to achieve the goal of efficient and high-purity synthesis.

I look at your question and inquire about the market price of 3,4-difluoro-5-methoxypyridine. However, this price often varies with time, place, quality and supply and demand changes, and it is difficult to determine.
The price of chemicals in the city is intertwined by many factors. The increase or decrease in the output of the origin and the fluctuation of the price of raw materials are all key. If the origin is abundant and the supply is sufficient, the price may decline; on the contrary, if the raw materials are scarce and the cost rises, the price will rise.
Furthermore, the demand situation also affects the price. If the demand for this product in a certain domain increases sharply, but the supply is not sufficient, the price must be high; if the demand is low, the merchant may reduce its price to promote.
In addition, the quality and the size of the transaction are also related to the price. High quality, the price is often higher than the average; buy in large quantities, or get preferential prices.
To know the exact market price, you can consult chemical raw material suppliers, traders, or explore chemical trading platforms to get the latest and accurate price information.

3,2,4-Dichloro-5-fluoropyridine is an organic compound, which is widely used in pesticides, medicine and other fields. The following is a brief description of its physical and chemical properties:
1. ** Physical properties **:
- ** Appearance **: Under normal conditions, it is mostly colorless to light yellow liquid or solid, which varies depending on the purity and preparation process, or shows different colors.
- ** Odor **: It has a special organic compound smell, pungent and uncomfortable, and needs protection during operation.
- ** Melting point and boiling point **: Melting point is about - 10 ° C, boiling point is about 200 ° C. Low melting point, room temperature or liquid; boiling point indicates that it needs to be properly heated to reach a gasified state.
- ** Solubility **: Insoluble in water, due to the large difference between molecular polarity and water; soluble in a variety of organic solvents, such as dichloromethane, chloroform, ether, etc., which is conducive to being used as a reactant or intermediate in organic synthesis.
- ** Density **: The density is about 1.5g/cm ³, which is larger than water. It will sink to the bottom when mixed with water.
2. ** Chemical properties **:
- ** Halogen atom activity **: containing chlorine and fluorine atoms, with high chemical activity. Chlorine and fluorine atoms can be replaced by nucleophiles to generate new organic compounds. For example, they react with sodium alcohol to form corresponding ethers. They are commonly used in drug structure modification and new pesticide research and development.
- ** Properties of the pyridine ring **: The pyridine ring is aromatic, stable and can undergo a variety of reactions. If it is oxidized under specific conditions, or reacts with electrophilic reagents for substitution, the nitrogen atom of the pyridine ring can provide electron pairs to coordinate with metal ions to form complexes for catalytic reactions or materials science.
- ** Stability **: Stable under normal storage and use conditions, avoid contact with strong oxidants, strong bases, etc., otherwise cause violent reactions, because it contains halogen atoms and pyridine rings, it may decompose in case of hot topics and open flames to produce toxic gases.

3,4-Dihydro-5-alkenyl pyrimidine needs to be carefully stored and transported.
It is delicate and sensitive to temperature and humidity. When storing, it is advisable to find a cool and dry place. The temperature should be controlled between 15 and 25 degrees Celsius, and the humidity should be stable at 40% to 60%. If the temperature is high, its quality will change and its effectiveness will gradually lose; if it is wet, it will be easy to deliquescent and damage its original properties.
When handling, everyone should handle it with care and do not let it be bumped. This is because of its delicate structure. If the external force is slightly increased, there is a risk of damage, resulting in damage to its quality.
Furthermore, the storage and transportation place must be kept away from fire and heat sources, and should not be co-located with oxidizers, acids, etc. Due to its active chemical properties, it is afraid of ignition and explosion in case of fire or heat; mixed with other chemicals, it is easy to cause chemical reactions and cause disasters.
The packaging should not be underestimated, and it must be tight to prevent it from leaking. Once leaked, it will not only damage itself, but also pollute the surrounding objects, harm and the environment.
In addition, the storage and transportation process needs to be recorded in detail. It should be clear from warehousing, handling to outbound, so that it can be traced back to the source. In case of changes, the cause can be quickly found and properly disposed of. In this way, the storage and transportation of 3,4-dihydro-5-alkenylpyrimidine are guaranteed.