2-Amino-3-chloro-5-methylpyridine

2-% hydroxy-3-chloro-5-methylpyridine, although this substance is not directly recorded in "Tiangong Kaiwu", it can also be explained by ancient chemical and technological knowledge.
Ancient chemical processes are mostly related to alchemy, pharmaceuticals, metallurgy, and brewing. 2-Hydroxy-3-chloro-5-methylpyridine, containing hydroxyl groups, chlorine atoms and methyl groups, has unique properties. In pharmaceuticals, it can be used as a key intermediate. Ancient healers often looked for herbs and stones to make good medicines, and the characteristics of this compound may help it make prescriptions. Its hydroxyl groups can participate in many chemical reactions, combine with other substances, and adjust the taste and efficacy of drugs. The introduction of chlorine atoms may change the stability and solubility of compounds, and in the preparation of pharmaceuticals, or help the preservation of drugs and the absorption of the human body.
Metallurgy, although it has not been directly involved in this matter, it may play a role in the preparation of some metal compounds. Ancient metallurgy, in order to obtain pure metals, often involves complex chemical reactions. This compound may be helpful in regulating the reaction conditions and promoting the transformation of metal ions.
As for the brewing industry, although traditional brewing relies on microbial fermentation, it may have special uses in the brewing environment or raw material processing. Such as adjusting the pH of the fermentation environment and inhibiting the growth of bacteria. Due to the characteristics of the compound, it may subtly affect the metabolism of microorganisms, thereby optimizing the quality and flavor of brewed products.
Although the use of this substance is not detailed in "Tiangong Kaiwu", it is inferred from the ancient process wisdom and chemical cognition that 2-hydroxy-3-chloro-5-methyl pyridine may have potential and important uses in pharmaceuticals, metallurgy, brewing and other fields, which can add color to various processes and promote the development of ancient techniques.

To prepare 2-amino-3-bromo-5-methylpyridine, the following ancient methods can be used.
First, a suitable pyridine derivative is used as the starting material. If a pyridine with a suitable substituent is found, the desired group is gradually introduced through clever reaction steps. First, try to introduce methyl at a specific position in the pyridine ring, which can be achieved by alkylation reaction. Select a suitable alkylation reagent, such as halomethane, and under appropriate reaction conditions, such as under the catalysis of a base, the halomethane undergoes a nucleophilic substitution reaction with the pyridine derivative, thereby connecting the methyl group to the designated position in the pyridine ring.
Then introduce the amino group. Nitrogen-containing reagents such as ammonia or its derivatives can be used for the introduction of amino groups. Nucleophilic substitution or reductive amination can be used. If nucleophilic substitution is used, a substituent on the pyridine ring needs to become a good leaving group, and then react with ammonia or amine reagents to realize the access of amino groups. If reductive amination is used, a suitable carbonyl group needs to be constructed on the pyridine ring first, and then it works with ammonia and reducing agents to achieve the introduction of amino groups.
As for the introduction of bromine atoms, bromination can be used. Common brominating reagents such as bromine, N-bromosuccinimide (NBS), etc. When the pyridine ring has methyl and amino groups, according to the positioning effect of the substituents on the pyridine ring, appropriate brominating reagents and reaction conditions are selected to precisely connect the bromine atoms to the target position. If bromine is used, the reaction can be carried out under the catalysis of appropriate catalysts, such as iron powder or its halides; if NBS is used, it is often necessary to generate bromine radicals under the action of light or initiators, thereby realizing the substitution of bromine atoms at specific positions in the pyridine ring.
All reaction steps require fine control of reaction conditions, such as temperature, reaction time, and the proportion of reactants, in order to achieve the best reaction effect and improve the yield and purity of the target product 2-amino-3-bromo-5-methyl pyridine. After each step of the reaction, suitable separation and purification methods, such as column chromatography, recrystallization, etc. are also required to remove impurities and provide pure raw materials for the next reaction before this specific pyridine compound can be obtained.

There are 2-hydroxy-3-chloro-5-methylpyridine available today, and I would like to know its market price. According to Guanfu's "Tiangong Kaiwu", although the price of this product is not detailed, I can infer it according to common sense and related products.
The price of various products often depends on supply and demand, difficulty in preparation, and quality of materials. If the preparation method of this 2-hydroxy-3-chloro-5-methylpyridine is complicated, it requires rare materials, and the preparation is difficult, labor-intensive and time-consuming, its price will be high. If the required materials are easily available, the production method is simple, and the quantity can be supplied in sufficient quantities, the price may be slightly flat.
Looking at the situation of market supply and demand, if this product is needed by many industry players, it is widely used, and the demand exceeds the supply, the price will rise. If the use is narrow and remote, the demand is few, and the supply exceeds the demand, the price will be suppressed.
Furthermore, the quality of it is also related to the price. Those who are pure and have few impurities will have a higher price than those who contain more impurities.
In today's world, the price of chemical products often changes from time to time, and varies from place to place. In order to know the exact price, you can get a more accurate number when you visit the chemical materials market, ask the merchants, or check the industry information and the price of the trading platform. However, by common sense, in ordinary times, if the production is not extremely difficult, the demand does not increase sharply or decrease sharply, the price should be based on the cost of labor and market conditions, or fluctuate within a certain range. But this is only an idea, and the actual price is ultimately subject to the market practice.

2-% Hydroxy-3-Chloro-5-methylpyridine This substance requires attention to many matters during storage and transportation.
First chemical stability. It contains hydroxyl groups, has certain reactivity, and is easy to react with a variety of substances. In case of strong oxidants, it may react violently, causing combustion or even explosion. Therefore, when storing, be sure to keep away from strong oxidants, such as perchloric acid, potassium permanganate, etc., and store it separately to prevent accidents.
The second is the requirement for environmental conditions. It is quite sensitive to temperature and humidity. Under high temperature, it may accelerate decomposition and deterioration; if the humidity is too high, it may also cause deliquescence and cause quality damage. Therefore, it should be stored in a cool, dry and well-ventilated place, the temperature should be controlled within a specific range, and the humidity should be maintained at a low level.
Furthermore, the packaging must be firm during transportation. This compound contains chlorine atoms and may be corrosive to a certain extent. If the packaging is damaged and leaks out, it will not only damage the goods, but also may corrode the transportation equipment and endanger the safety of transportation personnel. Therefore, the packaging material needs to be resistant to its corrosion, and it has good sealing performance to ensure that there is no risk of leakage during transportation.
In addition, due to the methyl content, this material may be flammable. Fireworks are strictly prohibited in the place of storage and transportation, and corresponding fire protection facilities should be equipped for emergencies. People who handle and come into contact with this object should also take protective measures, such as protective clothing, protective gloves and goggles, to avoid contact between skin and eyes to prevent injury. At the same time, it is necessary to be familiar with emergency treatment methods. If accidental contact or leakage occurs, it can be properly disposed of in a timely manner.

2-% hydroxy-3-chloro-5-methylpyridine is an organic compound with unique physical and chemical properties. Its shape may be a crystalline solid, and the melting boiling point has a specific value due to intermolecular forces. The presence of hydroxyl groups, chlorine atoms and methyl groups in the molecule greatly affects its properties.
Hydroxy groups are polar and can participate in the formation of hydrogen bonds, which makes the compound soluble in water and affects the interaction between molecules. The melting point and boiling point increase. Chlorine atoms have high electronegativity and strong electron-absorbing ability, which can change the electron cloud density of the pyridine ring and affect its chemical activity. For example, the electrophilic substitution reaction activity will be affected. The electron cloud density of the pyridine ring can be increased by methyl group as the power supply group, which also affects the check point and activity of the electrophilic substitution reaction.
In terms of chemical properties, due to the aromaticity of the pyridine ring, 2-% hydroxy-3-chloro-5-methyl pyridine can undergo electrophilic substitution reaction, and the localization effect of hydroxyl, chlorine atoms and methyl groups determines the introduction position of the substituent. The electron cloud density of the hydroxyl group is high, and the electrophilic reagents are easy to attack this position; although the chlorine atom is an electron-absorbing group, it has lone pairs of electrons, which also affects the reaction check point. In addition, hydroxyl groups can participate in reactions such as esterification and ether formation, giving the compound a variety of chemical activities.
2-% hydroxy-3-chloro-5-methylpyridine may have important applications in organic synthesis and medicinal chemistry due to its own physicochemical properties. It can be used as a synthetic intermediate to construct complex organic molecular structures through a series of reactions.