2-bromo-5-cyanopyridine

2-% cyanogen-5-aminopyridine is an important intermediate in the field of organic synthesis, and is widely used in many fields such as medicinal chemistry and materials science. Its synthesis methods are rich and diverse, and the ancient methods are described in detail below.
First, it can be started from 2,5-dihalopyridine. Take 2,5-dihalopyridine, place it in a reactor, add an appropriate amount of cyanide reagent, such as potassium cyanide or sodium cyanide, and use dimethyl sulfoxide (DMSO) or N, N-dimethylformamide (DMF) as a solvent. At an appropriate temperature, usually between 80 and 120 ° C, the cyanyl substitution reaction is carried out. After the reaction is completed, it can be purified by extraction, column chromatography and other means to obtain 2-cyano-5-halopyridine. Subsequently, 2-cyano-5-halopyridine is combined with an ammonia source, such as liquid ammonia or ammonia water, under the catalysis of an appropriate catalyst, such as palladium carbon or copper salt, at a certain temperature and pressure, the temperature is about 100-150 ℃, the pressure depends on the specific situation, and then the substitution of amino groups to halogen atoms is realized, and finally 2-cyano-5-aminopyridine is obtained.
Second, pyridine derivatives are used as starting materials. First, the specific position of the pyridine ring is functionalized and a suitable substituent is introduced, and the target molecular structure is gradually constructed through a multi-step reaction. For example, a group that can be converted to cyano is introduced at the 2nd position of the pyridine ring, and a group that can be converted to amino is introduced at the 5th position. A series of reactions such as nucleophilic substitution, oxidation, and reduction can be used to skillfully convert each group in a specific order, and finally 2-cyano-5-aminopyridine is obtained. This route requires precise control of the reaction conditions. The yield and selectivity of each step of the reaction are related to the yield and purity of the final product.
Third, there are also methods for synthesizing by the strategy of heterocyclic ring construction. Appropriate nitrogen-containing heterocyclic precursors are selected to construct pyridine rings through cyclization reaction, and cyano and amino groups are introduced at the 2nd and 5th positions during or after cyclization. This method requires in-depth understanding of the reaction mechanism and careful design of the reaction route to efficiently synthesize the target product.

The main uses of 2-% ether-5-alkylphenyl are:
It is used in medicine. In medicine, 2-ether-5-alkylphenyl is often the key raw material. This synthetic agent may cure various diseases. Because of its special chemical conformation, it can precisely fit with biological macromolecules in the body, regulate physiological functions, and achieve the effect of curing diseases and saving people. For example, a certain type of drug for specific inflammation, with 2-ether-5-alkylphenyl as the starting material, through many delicate chemical reactions, can be made into a good medicine with targeted anti-inflammatory power, which can solve the pain of inflammation in patients.
The second is the way of material creation. In the field of materials science, this substance can be used as a modification aid. Adding an appropriate amount of 2-ether-5-alkylbenzene to polymer materials can significantly change the properties of materials. For example, after modifying plastics with poor flexibility, the flexibility of plastics is greatly increased, and the mechanical strength is also maintained or improved. In this way, the application of polymer materials in packaging, machinery manufacturing and many other industries is broadened.
Three are the needs of scientific research. In the laboratory of chemical research, 2-ether-5-alkylphenyl is an indispensable reagent. Scientists use its unique chemical activity to explore novel chemical reaction pathways and synthesize unprecedented compounds. This process is like exploring a new path in the maze of chemistry. Every reaction attempt based on 2-ether-5-alkylphenyl may open a door to a new field of chemistry, inject new vitality into the development of chemistry, and promote the progress of both theory and practice.

2-% E6% BA% B4 - 5-%E6%B0%B0%E5%9F%BA%E5%90%A1%E5%95%B6, also known as diboropentamine to it, is a strange quality, and is often involved in alchemy and mechanism techniques.
Its quality has all kinds of wonders. Looking at its color, it often shows a faint silver-blue light, just like the strange light looming in the starry night sky, hazy and charming. Touch it, I feel warm at first, as if I am holding a warm jade, but when I feel a little bit of coolness passing through my fingers, the chill is cold.
Its nature is lively, and when it encounters fire, it bursts with gorgeous brilliance. The flame color is blue and blue, dazzling, and accompanied by a slight crackling sound, like a dragon singing in the abyss, and like a phoenix singing in the forest, which is quite wonderful. Placed in water, it is insoluble and floats on it, like a light boat, and where it touches the water, there are traces of white gas curling and rising, if it is surrounded by clouds and mists, it is like Xianjia Rui Ai.
As for its use, it can increase its ingenuity in the way of organs and equipment. If it is put into tenons and tenons, it can make the equipment sturdy and abnormal, not damaged for a long time, and the operation is smoother, just like the work of heaven, it is natural. In the way of alchemy and pharmaceuticals, it is also a precious supplement. Throwing it into the pill furnace can adjust the qi of various medicines, promote the integration of medicinal properties, and make the effect of medicinal pills more outstanding. Taking it may strengthen the body or prolong life. However, the refining method is extremely complicated, and those who are not proficient in this way cannot do it.

2-% E6% BA% B4 - 5-%E6%B0%B0%E5%9F%BA%E5%90%A1%E5%95%B6, both of which are extraordinary and have many unique chemical properties.
Let's talk about the 2-hydroxyl group first, which is famous for its reactivity. The oxygen atoms in the hydroxyl group have strong electronegativity, which makes the hydrogen-oxygen bond polarity quite large. This property makes it very easy to participate in various chemical reactions. In organic reactions, hydroxyl groups can be replaced. For example, in halogenation reactions, hydroxyl groups can be replaced by halogen atoms, resulting in the generation of various halogenated hydrocarbons. At the same time, hydroxyl groups can undergo dehydration reactions. If under suitable conditions, intramolecular dehydration can produce olefins, and intermolecular dehydration will form ether compounds. In addition, hydroxyl groups have a certain acidity. Although the acidity is weak, they can react with bases to form corresponding salts.
As for 5-aminopyridine, it also has its own unique features. The amino group is an electron donor group, and the pyridine ring is aromatic. The electron cloud density on the pyridine ring is increased by the action of the amino group, especially in the ortho and para-positions. In this way, the electrophilic substitution reactivity of 5-aminopyridine is improved, and the reaction check points are mostly concentrated in the ortho and para-positions of the amino group. Moreover, the amino group is basic and can neutralize with acids to form salts. The pyridine ring itself can also participate in some special reactions, such as coordination with metal ions to form stable complexes, showing its unique chemical activity and coordination ability.
These two chemical properties are rich and diverse, and they are widely used in many fields such as organic synthesis, drug development, materials science, etc. They are an indispensable part of chemical research and industrial production.

In today's market, there are two or five times as many as there are now, and each of them has its own size. In the past, the system of management was determined by the imperial court, in order to deal with the price, but the market was more expensive, and the price was also more floating.
Two kinds of management, the shape is small, and the weight is also small. In the city, its power is limited. If it is easy to eat, the price will not rise; if you want to buy cloth, you will also get a ruler. However, because of its convenience, in some small transactions, it is convenient, so there are many people in the market who like to use it. Its price, if you encounter a lack of things, may be able to get a slightly higher value; if it is a famine, the scarcity of things, its value or drop.
As for the five-year-old, heavy and large, the strength of the two is too much. With it, you can get a fight; easy cloth and silk, you can buy. Because of its sufficient weight, good quality, and rich business, it can be used more often, so as to block the medium of trade. The goods in the city are flat, and the five-year-old grid is determined; however, if there is a problem in the market, there may be a big hoarding and a strange situation, and there may also be waves.
Of course, two or five years, depending on the height of the market, all are affected by factors such as the price, the apology of the goods, and the amount of transactions. When people in the city trade, they must check the market and weigh the pros and cons before they can get it.