2-chloro-5-iodopyridine 98% 2g

2-Chloro-5-iodopyridine, with a content of 98%, 2 grams, is a useful chemical substance in organic synthesis. It is widely used in the field of medicinal chemistry and is often a key intermediate for the synthesis of specific drugs. The structure of the geinpyridine ring is stable and has unique electronic properties. Chlorine and iodine atoms can participate in a variety of chemical reactions to construct complex drug molecular structures to obtain specific physiological activities.
In the field of materials science, it also has important uses. It can be introduced into polymer materials through specific chemical reactions, giving novel properties to the materials, such as improved electrical conductivity and optical properties.
In the field of pesticide chemistry, it also plays an important role. By ingeniously designing chemical reactions, using 2-chloro-5-iodopyridine as raw materials, pesticides with high insecticidal, bactericidal or herbicidal properties can be synthesized to help agricultural production.
In addition, in the synthesis of fine chemicals, as a basic raw material, it can participate in various organic reactions, and many fine chemicals with special purposes are derived. They are widely used in fragrance, dye and other industries, providing an indispensable material basis for the development of various industries.

2-Chloro-5-iodopyridine, content 98%, specification 2g, this medicine should be placed in a cool, dry and well-ventilated place. Its delicate nature, fear of heat and moisture, if heated, the efficacy of the drug is easy to lose; if damp, fear of qualitative change.
and must be stored in isolation from strong oxidants, strong bases and the like. Strong oxidants are strong, coexisting with them, or reacting violently, causing danger; strong bases are corrosive, and contact with them can also damage their quality.
Store in a place that should be out of reach of children to prevent them from accidentally touching and eating by mistake, causing disasters. It also needs to be properly managed by a special person and recorded in detail to ensure its safety and constant quality. In this way, it can be stored for a long time in case it is needed from time to time.

To prepare 2-chloro-5-iodopyridine, the preparation method is as follows:
First use 5-amino-2-chloropyridine as the starting material, which is the key foundation. Dissolve 5-amino-2-chloropyridine in an appropriate amount of acidic solution, such as hydrochloric acid solution, so that it is fully dissolved to form a uniform mixture system. Then, under low temperature and stirring conditions, slowly add an appropriate amount of sodium nitrite solution. This process requires extreme caution, because the rate of addition of sodium nitrite and the reaction temperature have a great influence on the reaction process. The purpose of this step is to form a diazonium salt intermediate. Sodium nitrite reacts with the amino group in 5-amino-2-chloropyridine to form a diazonium salt.
After forming a diazonium salt, take another container and prepare a solution of potassium iodide. Carefully add this potassium iodide solution to the system containing diazonium salts. The diazonium salt reacts rapidly with potassium iodide, and the diazonium group is replaced by an iodine atom, resulting in a crude product of 2-chloro-5-iodopyridine. During this reaction, the color state of the solution may change significantly, and the progress of the reaction can be preliminarily judged based on this.
However, the obtained product is crude and needs to be further purified. A method such as column chromatography can be used to select a suitable silica gel as the stationary phase and elute with a specific proportion of eluent, such as a mixed solvent of petroleum ether and ethyl acetate. Through column chromatography, impurities can be effectively separated, the purity of the product can be improved, and the purity standard of 98% can be achieved. The eluent containing the target product is collected, and the solvent is removed by vacuum distillation to obtain a pure 2-chloro-5-iodopyridine product. To obtain an amount of 2g, the dosage of each raw material can be adjusted appropriately according to the above ratio.

I don't know what "2-chloro-5-iodopyridine" involves in "Tiangong Kaiwu". However, with common sense, if you want to know the price of 2g of this thing and the purity is 98%, you should ask the market and merchants. In today's world, trade is complicated, and prices often change from time to time and vary from city to city. Or you can visit the merchants of chemical reagents, or find them on the e-commerce platform, and there may be prices there. However, if this thing is not listed in the book, it is difficult to answer according to it. If you follow the ancient law, those who want to know the price must go to the market in person, negotiate with the merchants, check their supply and demand, and measure their advantages and disadvantages before they can get their approximate price. Although the world is different, but seeking the reason for prices, or there are similarities, the market conditions shall prevail, and extensive inquiries and interviews can be obtained before the true price.

To determine the purity of 2-chloro-5-iodopyridine, the following methods can be used.
High-performance liquid chromatography (HPLC) is the first. Take an appropriate amount of 2-chloro-5-iodopyridine sample, dissolve it in a suitable solvent, and prepare a solution of a certain concentration. Select an appropriate column, such as a C18 column, and use the mobile phase to drive the sample to separate in the column. The mobile phase can be selected according to the nature of the sample, such as methanol-water system, and adjust its ratio. Set parameters such as flow rate and detection wavelength, 2-chloro-5-iodopyridine or peak at a specific retention time, and its purity can be calculated according to the peak area compared with the standard product peak area of known purity.
Gas chromatography (GC) is also feasible. If the sample has a certain volatility, it will be vaporized and enter the column with the carrier gas. Choose the appropriate stationary phase, and separate it according to the difference in the distribution coefficient between the stationary phase and the carrier gas of each component of the sample. By measuring the peak area of each component and comparing it with the standard product, its purity can also be measured.
Melting point determination is also helpful for purity judgment. The pure state of 2-chloro-5-iodopyridine has a specific melting point range. The melting point of the sample is measured by a melting point instrument. If the measured melting point is consistent with the melting point of the pure product recorded in the literature, and the melting range is narrow, about 1-2 ° C, the purity can be proved to be high. If the melting range is wide and the melting point is deviated, the purity is poor.
In addition, elemental analysis can measure the content of each element in the sample. After accurately weighing the sample, complete combustion or chemical reaction, the content of chlorine, iodine, carbon, hydrogen, nitrogen and other elements is measured. Compared with the theoretical value, if the deviation is small, the purity is high; if the deviation is large, it contains more impurities. < Br >
The purity of 2-chloro-5-iodopyridine can be accurately determined by this method.