2-Bromo-5-nitrothiophene

2-%E6%BA%B4-5-%E7%A1%9D%E5%9F%BA%E5%99%BB%E5%90%A9 (2-Amino-5-chlorobenzoic acid) is a crucial raw material in the field of organic synthesis, and is widely used in many industries such as medicine, pesticides and dyes. The following is an ancient saying to describe its main uses:
In the way of medicine, 2-%E6%BA%B4-5-%E7%A1%9D%E5%9F%BA%E5%99%BB%E5%90%A9 is a key intermediate. It can be used in organic synthesis to make various drugs with outstanding efficacy through many delicate reactions. For example, it can prepare antibacterial and anti-inflammatory drugs. It can act on the physiological and metabolic pathways of bacteria, inhibit the growth and reproduction of bacteria, and solve the disease of human inflammation, so that patients can heal. It can also be used to synthesize anti-tumor drugs. By precisely acting on specific targets of tumor cells, it interferes with the abnormal proliferation of tumor cells and contributes to the cause of anti-cancer.
In the field of pesticides, this substance is also important. With it as a starting material, through clever chemical changes, highly efficient pesticides can be prepared. Such pesticides have strong lethality to a variety of pests and can effectively protect crops from insect infestation. Or act on the nervous system of pests, causing their nerve conduction disorder, causing their movement disorders and death; or affect the digestive system of pests, making them unable to take in nutrients normally, eventually leading to the death of pests, ensuring a good harvest of crops and maintaining the foundation of people's livelihood.
As for the dye industry, 2-%E6%BA%B4-5-%E7%A1%9D%E5%9F%BA%E5%99%BB%E5%90%A9 has also made extraordinary contributions. After specific processes, dyes with brilliant colors and good stability can be synthesized. Its molecular structure is designed and modified to absorb and reflect light of specific wavelengths, showing rich colors. It can be used for fabric dyeing to make the fabric color bright and long-lasting, improve the beauty and quality of the fabric, and play an important role in the textile printing and dyeing industry, bringing colorful clothing and fabric products to the world.

The synthesis method of 2-cyanogen-5-fluoro-pyridine has been known for a long time and is described in detail below.
First, using pyridine as the initial raw material, the halogen atom is introduced through the halogenation reaction, and then the cyanide group is introduced through the cyanation step. This is the key transition. Under suitable reaction conditions, the cyanyl group replaces the halogen to obtain the cyanide-containing pyridine derivative. Then, through a specific fluorination reaction, the fluoro group is ingeniously introduced to eventually form 2-cyanogen-5-fluoro-pyridine. This approach requires fine control of the reaction conditions of each step, such as temperature, reagent ratio, reaction time, etc., in order to improve the yield and purity of the product.
Second, a different approach is taken, using fluorine-containing pyridine compounds as the starting materials. First, the appropriate protective group is operated to protect the specific functional group and avoid being affected in the subsequent reaction. Then, the cyanide group is introduced into the specific position of the pyridine ring in the appropriate reaction environment with a suitable cyanide reagent. After the cyanide group is successfully introduced, the protective group is carefully removed to obtain the target product. This method focuses on the application of protection and de-protection strategies, and requires high selectivity in the reaction. The operation also needs to be careful and meticulous.
Third, the strategy of building through heterocycles can also be considered. Using appropriate nitrogen, carbon, fluorine and cyanide-containing small molecules as raw materials, the pyridine ring is directly constructed through multi-step cyclization reaction, and the cyano and fluoro groups are precisely introduced into the target position. Although this strategy is complicated in steps, it may have potential advantages in terms of atomic economy and step simplification. Only by in-depth understanding of the mechanism of cyclization and careful design of the reaction path can the synthesis of 2-cyano-5-fluoro-pyridine be successfully realized.

2-%E6%BA%B4-5-%E7%A1%9D%E5%9F%BA%E5%99%BB%E5%90%A9, the nature is strong and firm, like the quality of gold and stone. Its color is mostly plain white, and occasionally there is a green and blue color hidden in it, smooth and warm, and the tentacles are cool, just like ice and jade bones, slippery without leaving hands.
This stone is dense and delicate in texture. It looks like a picture scroll in heaven, or stretches like mountains and rivers, or like clouds and mists, all of which are wonderful in nature. The sound of knocking is clear and clear, like a jade chime, the lingering sound is curling, and the rhyme is long. Its density is quite large, placed in the palm of the hand, quite sinking, showing its quality is thick and solid.
And because of its acid and alkali resistance, it will not corrode over time, and can be retained in the world for a long time without losing its true state. Under the high temperature and extreme heat, it can also be as stable as Mount Tai, without cracking or melting, and keep its inherent nature. Therefore, it is often valued by elegant scholars, or carved into tools, or Chen Yu in several cases to enhance the charm of elegant rooms and honor the taste of the owner.

In today's market, for the second and fifth years, the quality and quality of the products are not the same. In the past, the quality of the products made in the past was bright, the quality of the officials was high, and the city's trust was increased, and its quality was also solid.
If the second and fifth years are in good condition and well-made, they will be well received in the collector's market. However, there are also things in circulation in the market that have been worn and worn for a long time due to age. This value has been reduced by itself. It is generally two years of good quality, and it may be up to ten years. If there are special editions, land sales, etc., the value or more will be increased, and the 100-year-old position will not be known.
Five years, since the beginning of Emperor Wu, the world has been around for a long time. Because of its shape and weight, it is still used in the generation. Ordinary five, the survival of the world, the market or the general market, often one. However, there are many high-quality products, such as some specific dynasties and specific bureaus, those with exquisite characters and shapes, can rise to ten or even hundreds. If there are rare editions, such as rare editions, mothers, their value can be estimated, and they can be hundreds or even higher.
The second and fifth editions of the city, and the fixed price are all based on factors such as quality, edition, and the amount of stock in the world.

2-%E6%BA%B4-5-%E7%A1%9D%E5%9F%BA%E5%99%BB%E5%90%A9%E5%9C%A8%E5%82%A8%E5%AD%98%E4%B8%8E%E8%BF%90%E8%BE%93%E4%B8%AD%EF%BC%8C%E5%BD%93%E4%B8%87%E5%8F%91%E6%84%8F%E5%8F%91%E5%88%B6%E3%80%82
%E5%82%A8%E5%AD%98%E4%B9%8B%E9%97%B4%EF%BC%8C%E5%BF%85%E9%A1%BB%E9%81%BF%E5%85%8D%E4%B8%8E%E9%87%8D%E9%87%8F%E7%89%A9%E4%BD%93%E6%89%93%E6%8C%81%EF%BC%8C%E5%8F%88%E5%BF%85%E9%A1%BB%E8%BF%9C%E7%A6%BB%E7%82%B9%E7%83%BD%E4%B8%8E%E7%82%89%E7%82%89%E7%83%BD%E7%82%B9%E3%80%82%E5%85%B6%E5%9C%A8%E5%82%A8%E5%AD%98%E7%9A%84%E5%9C%BA%E6%89%80%EF%BC%8C%E5%BF%85%E9%A1%BB%E6%98%AF%E5%B9%B3%E6%87%89%E3%80%81%E9%97%B4%E6%98%AF%E5%87%8F%E5%B0%91%E7%9A%84%E5%9C%BA%E6%89%80%EF%BC%8C%E4%B8%94%E5%BF%85%E9%A1%BB%E6%9C%89%E8%B6%85%E5%87%BA%E5%88%86%E9%99%A9%E6%84%9F%E7%9A%84%E9%98%B2%E7%81%AB%E3%80%81%E9%98%B2%E6%B0%B4%E8%83%BD%E5%8A%9B%E3%80%82%E5%85%B6%E7%94%A8%E8%89%B2%E5%B9%B2%E5%B1%95%E7%9A%84%E7%9B%B8%E6%9C%BA%E6%98%BE%E5%BE%97%E7%9A%84%E7%89%A9%E4%BD%93%E5%BD%92%E7%B1%BB%E6%94%BE%E7%BD%AE%EF%BC%8C%E4%B8%8D%E5%BE%97%E6%B7%B7%E6%94%BE%E3%80%82
%E8%BF%90%E8%BE%93%E4%B9%8B%E9%97%B4%EF%BC%8C%E5%85%88%E8%A6%81%E6%A3%80%E6%9F%A5%E8%BF%90%E8%BE%93%E7%9A%84%E8%BD%A6%E8%BE%86%E6%98%AF%E5%90%A6%E5%AE%8C%E5%A5%87%EF%BC%8C%E8%BD%A6%E8%BE%86%E4%B8%AD%E6%98%AF%E5%90%A6%E6%9C%89%E5%8D%B1%E9%99%A9%E7%89%A9%E5%93%81%E3%80%82%E8%BF%90%E8%BE%93%E4%B9%8B%E4%BA%8B%EF%BC%8C%E5%BF%85%E9%A1%BB%E7%94%A8%E7%A6%BB%E7%A7%8D%E5%86%92%E6%B2%BB%E7%9A%84%E8%BD%A6%E8%BE%86%EF%BC%8C%E4%B8%94%E8%BD%A6%E8%BE%86%E9%A1%B9%E9%87%8F%E4%B8%8D%E5%BE%97%E8%B6%85%E8%BF%87%E8%BD%A6%E8%BE%86%E7%9A%84%E8%87%AA%E8%83%BD%E5%8A%9B%E3%80%82%E5%9C%A8%E8%BF%90%E8%BE%93%E8%BF%87%E7%A8%8B%E4%B8%AD%EF%BC%8C%E8%BF%90%E8%BE%93%E4%BA%BA%E5%91%98%E5%BF%85%E9%A1%BB%E6%89%A7%E8%A1%8C%E4%B8%93%E4%B8%9A%E7%9A%84%E6%95%99%E7%A8%8B%E5%92%8C%E6%B5%81%E7%A8%8B%EF%BC%8C%E9%81%BF%E5%85%8D%E6%89%A7%E8%A1%8C%E8%BF%87%E7%A8%8B%E4%B8%AD%E4%BA%A7%E7%94%9F%E7%82%B9%E7%83%BD%E3%80%81%E7%82%89%E7%82%89%E7%83%BD%E7%82%B9%E7%AD%89%E7%83%88%E7%82%89%E4%BA%8B%E6%95%85%E3%80%82
%E5%85%B6%E7%94%A8%E8%89%B2%E5%B9%B2%E5%B1%95%E7%9A%84%E7%9B%B8%E6%9C%BA%E6%98%BE%E7%A4%BA%E7%9A%84%E7%89%A9%E4%BD%93%EF%BC%8C%E5%9C%A8%E5%82%A8%E5%AD%98%E4%B8%8E%E8%BF%90%E8%BE%93%E4%B8%AD%EF%BC%8C%E5%BF%85%E9%A1%BB%E5%AE%9E%E8%A1%8C%E4%B8%93%E4%B8%9A%E7%9A%84%E7%AE%A1%E7%90%86%E4%B8%8E%E6%A3%80%E6%B5%8B%EF%BC%8C%E4%BB%A5%E4%BF%9D%E8%AF%81%E5%85%B6%E5%AD%98%E6%9D%90%E5%92%8C%E8%BF%90%E8%BE%93%E7%9A%84%E5%AE%89%E5%85%A8%E3%80%82%E5%93%88%E5%93%88%EF%BC%8C%E6%9C%AC%E5%B0%8F%E5%B0%8F%E7%9A%84%E7%94%A8%E5%BF%83%E4%BA%8E%E6%9C%AC%E4%BA%BA%E7%9A%84%E7%94%9F%E4%BA%A7%E4%B8%94%E5%88%86%E4%BA%AB%E7%9A%84%E7%9F%A5%E8%AF%86%E5%85%B6%E5%AE%9E%E5%B7%B2%E5%9C%A8%E5%88%86%E4%BA%AB%E4%BA%8E%E5%A4%A7%E5%AE%B6%E4%BA%86%EF%BC%81