2-hydrazinylpyridine

2-Carbonyl glutaric acid, its main use, in "Tiangong Kaiwu", is often used in chemical and pharmaceutical fields.
At the end of the chemical industry, 2-carbonyl glutaric acid is often an important raw material for organic synthesis. Can be used as an intermediate to produce a variety of organic compounds. If through a specific chemical reaction, it can combine with other reagents to form organic molecules with different structures and functions. This is of great significance in the fine chemical industry, such as the preparation of fragrances and dyes. Taking the preparation of fragrances as an example, through a clever synthesis path, 2-carbonyl glutaric acid can be converted into a substance with a unique aroma, adding new elements to the preparation of fragrances.
In the field of medicine, its use should not be underestimated. Due to its special chemical structure, it can participate in a variety of drug synthesis. It is either a key component of active ingredients, or acts as a bridge in the drug synthesis process, helping to build a specific structure of drug molecules. Medical research has shown that some drugs with the potential to treat specific diseases rely on the participation of 2-carbonylglutaric acid in the synthesis process. Through precise chemical reaction regulation, drugs can be given better pharmacological activity and bioavailability, opening up new avenues for pharmaceutical research and development. Therefore, 2-carbonylglutaric acid plays an important role in both the chemical and pharmaceutical fields, providing a key foundation for the preparation and development of many products, and is an indispensable chemical substance.

2-%E8%82%BC%E5%9F%BA%E5%90%A1%E5%95%B6%E7%9A%84%E7%89%A9%E7%90%86%E6%80%A7%E8%B4%A8%E6%9C%89%E5%A6%82%E4%B8%8B%E5%87%A0%E7%A7%8D:
First, it has the character of firmness. "Tiangong Kaiwu" says: "Where iron is separated and cooked, it is raw when it is not fried when it is out of the oven, and it is cooked when it is fried. The raw and cooked phases are combined, and the steel is refined." 2-%E8%82%BC%E5%9F%BA%E5%90%A1%E5%95%B6, its quality is hard, it can bear weight and pressure without folding, and it is difficult to bend when it encounters force. It is like the edge of a sharp blade, which can break through a solid object. With its strong quality, it can be used for equipment and weapons before it can be used.
Second, it has good heat transfer. Taking cookware as an example, iron cookware has rapid and uniform heat transfer. As described in "Tiangong Kaiwu": "Where the kettle is stored in water and subject to fire, it is used for daily use." 2-%E8%82%BC%E5%9F%BA%E5%90%A1%E5%95%B6 making a kettle, the food in the kettle can be quickly heated, evenly cooked, and will not be partially burnt. This heat transfer property is indispensable in the cooking industry.
Third, it can be forged. In "Tiangong Kaiwu": "When making a military weapon, make a knife, axe and other things, make it divided into two weights, and the iron is bonded one by one. First, use the wrought iron (wrought iron) as the body, and then wrap it with the iron (steel), and wave the hammer into the fire, saying'stick to steel '." 2-%E8%82%BC%E5%9F%BA%E5%90%A1%E5%95%B6 after heating, it can be forged into various shapes according to the wishes of the craftsman, or for swords, or for agricultural tools, or for utensils, which can meet different needs and show its various uses.
Fourth, it is easy to rust. Iron is prone to rust when exposed to water and air, which is one of its major drawbacks. However, the ancients also had countermeasures, such as oiling, painting, etc., to block air and water to slow down the rate of rust. Although it cannot be eliminated, it can also prolong the service life of iron.

2-% pentylphenol, with its unique chemical properties, is related to many industrial and daily applications, and cannot be ignored.
This substance is colorless to light yellow liquid and has a special phenolic odor. Its solubility is slightly soluble in water, but easily soluble in organic solvents such as alcohols and ethers. This characteristic is derived from the interaction between hydrophilic hydroxyl groups and hydrophobic amyl groups in its molecular structure.
In terms of chemical activity, the phenolic hydroxyl group of 2-% pentylphenol is active. When exposed to alkali, the hydrogen in the phenolic hydroxyl group is easily replaced by alkali metal ions to form corresponding phenolic salts. This reaction is of great significance in the preparation of polymer materials such as phenolic resins. At the same time, due to the presence of phenolic hydroxyl groups, it can participate in esterification reactions, react with organic acids or anhydrides under specific conditions to form ester compounds, which are widely used in the synthesis of fragrances and plasticizers.
In addition, electrophilic substitution reactions are prone to occur on the 2-% pentylphenol phenyl ring. Due to the phenolic hydroxyl group as the power supply, the electron cloud density of the benzene ring is increased, and reactions such as halogenation and nitrification are easier to proceed. For example, when reacted with halogen elements under appropriate conditions, halogen atoms will preferentially replace phenyl ring ortho and para-hydrogen atoms to form halogenated products, which are crucial in the synthesis of pesticides and pharmaceutical intermediates.
Not only that, 2-% pentylphenol also has certain antioxidant properties, which can capture free radicals in some organic systems and inhibit the oxidation process. Therefore, it is often used as an antioxidant in easily oxidized substances such as rubber and grease to prolong the service life of the product.

2-Cyanopyridine is a crucial intermediate in organic synthesis, and there are many synthesis methods. Although the synthesis of 2-cyanopyridine is not directly explained in Tiangongkai, it can be based on the ancient chemical process ideas and combined with current chemical knowledge.
One is the pyridine-2-carboxylic acid method. This is the reaction of pyridine-2-carboxylic acid and ammonia under the action of a dehydrating agent. As the saying goes in Tiangongkai requires suitable conditions for material transformation, and this reaction also requires specific reagents to create an environment. Pyridine-2-formic acid and ammonia are used as raw materials. When a dehydrating agent, such as phosphorus pentoxide, is present, heating prompts the reaction between the two. After the dehydration process, the carboxyl group is converted to a cyanyl group, and 2-cyanopyridine is obtained. The key role of the dehydrating agent is, as described in "Tiangong Kaiwu", many processes require the help of mediators to promote the reaction.
The second is the 2-chloropyridine method. 2-chloropyridine reacts with cyanide reagents such as cuprous cyanide in appropriate solvents and temperatures. The ancient process focuses on controlling the temperature and environment, and the same is true for this reaction. 2-Chloropyridine and cuprous cyanide are placed in a suitable organic solvent, such as N, N-dimethylformamide, heated to a certain temperature, and the chlorine atom is replaced by a cyanyl group to form 2-cyanopyridine. The choice of solvent in the reaction is important, and it needs to be able to dissolve the reactants and provide a stable environment for the reaction, similar to the clever selection of reaction media by the ancients.
The third is the pyridine method. Pyridine reacts with cyanide reagents under the action of a catalyst. "Tiangong Kaiji" often mentions that reactions occur with the help of external force, and this catalyst is used for this external force. Using pyridine as the starting material, in the presence of catalysts such as palladium, it reacts with cyanide reagents such as potassium cyanide. Through the catalytic process, a cyanyl group is introduced at a specific position on the pyridine ring to generate 2-cyanopyridine. The catalyst plays a role in reducing the activation energy of the reaction, making the reaction more likely to occur, just like the ancients used the force of nature to optimize the process.
All the above methods for synthesizing 2-cyanopyridine require fine operation and suitable conditions. Although it is not originally published in Tiangong Kaiwu, the chemical principles are in the same vein in ancient and modern times, and they are all the embodiment of human wisdom in the transformation and utilization of substances.

Where a binary tube is used, it is important to pay attention to it.
The first thing to pay attention to is its performance. The binary tube has the property of directional flow, and the flow can flow from the pump to the pump. If it is connected in the opposite direction, the road will not be blocked, and even the device will be blocked. As "Tiangong Wuwu" said, "The way to use the device is the first to understand the reason", so before connecting to the pipeline, the performance must be checked, which can be judged by the tube body or measurement.
times and determined. Such as the maximum rectification flow, this is the maximum average flow that the secondary tube can withstand. If this value is exceeded, the secondary tube will be damaged, resulting in performance degradation, or even loss. Another example is the highest reverse working speed. If the reverse speed exceeds this value, the secondary tube or wear will lose the directional performance. It is necessary to choose the best way and the best device. According to the requirements of the best way, the best way to combine two pipes is to ensure that the best way is fixed.
Furthermore, note the working environment. The performance of the second tube is affected by the degree of resistance. Lift, reverse flow and flow increase, and forward drop. In high-pressure environments, it is especially necessary to consider this characteristic, or devices with good resistance, or measures to reduce the resistance.
In addition, welding two pipes also need to be paid attention to. Welding should be short, and the degree should not be high, so as to avoid high performance. And the welding materials and welding aids should also be combined, and the welding capacity should be guaranteed, so as to avoid welding and missed welding. In addition, the use of two tubes should be done carefully in terms of performance, performance, environment, and welding, so as to ensure the performance of the device and ensure the operation of the road.