3-Pyridinecarboxylic acid, 5-chloro-2-fluoro-

5-Alkane-2-ene-3-heptanoic acid, which is widely used in the chemical industry.
In the field of organic synthesis, it is a key intermediate. Due to the double bond and triple bond in the molecular structure, as well as the active functional group of carboxyl group, many complex and functional organic compounds can be derived through various chemical reactions. For example, by means of acid-catalyzed esterification of carboxyl groups and alcohols, corresponding ester compounds can be prepared. Such esters are widely used in flavors, coatings and other industries. For example, some synthetic fragrances rely on this method to produce, giving the product a unique aroma.
In the field of materials science, 5-alkane-2-ene-3-heptanoic acid also plays an important role. Through the polymerization of double bonds and triple bonds, polymer materials with special properties can be synthesized. For example, the synthesized polymer may have excellent mechanical properties and thermal stability, which is very useful in aerospace, automobile manufacturing and other fields that require strict material properties. High-performance composites required for some parts in aerospace may be synthesized from it.
In addition, in the field of medicinal chemistry, it should not be underestimated. Due to its special structure, it can be used as a lead compound for structural modification and optimization. Chemists explore new compounds with biological activity through the modification of their functional groups, providing the possibility for the development of new drugs. In the development of some potential anti-cancer and anti-inflammatory drugs, research may be carried out on the basis of 5-alkane-2-ene-3-heptanoic acid.
In summary, 5-alkane-2-ene-3-heptanoic acid has important uses in organic synthesis, materials science, pharmaceutical chemistry and other fields due to its unique structure, which is of great significance to promote the development of related industries.

The physical properties of 5-hydroxy- 2-pentanone-3-carboxylic acid are as follows:
This substance is a colorless to light yellow liquid and is relatively stable at room temperature and pressure. It has a certain volatility, a specific odor, and is slightly irritating, but it is not very pungent.
The boiling point of 5-hydroxy- 2-pentanone-3-carboxylic acid is quite high, about [X] ° C. This is due to the interaction of hydrogen bonds between molecules, which binds molecules tightly, and more energy is required to gasify them. Its melting point is relatively low, about [X] ° C, and it condenses as a solid state in a low temperature environment.
In terms of solubility, it is soluble in a variety of organic solvents, such as ethanol, ether, etc., because it can form similar intermolecular forces with organic solvent molecules, which is in line with the principle of "similar miscibility". It also has a certain solubility in water, because polar groups such as hydroxyl and carbonyl in the molecule can form hydrogen bonds with water molecules to enhance their dispersion in water.
The density is slightly larger than that of water, about [X] g/cm ³, and it will sink to the bottom when placed in water. Its viscosity is moderate, and its flow performance is good. It is easy to flow and transfer in the liquid state. < Br >
In addition, the refractive index of the substance is also a specific value, about [X], which can be used as an important basis for optical analysis and identification. Under different temperature and concentration conditions, its refractive index will change accordingly, so its purity and concentration can be inferred by refractive index measurement.

The chemical properties of 5-alkane-2-ene-3-alkyne and its carboxylic acid are relatively stable. When these three types of organic groups coexist in the same compound, although each has its own unique activity, the interaction also makes the overall properties tend to a specific stable state.
The alkane part is connected by a single bond of carbon and carbon, and the structure is saturated. Its carbon and hydrogen bond energy is quite high, so its chemical properties are relatively inert. Under normal temperature and pressure, it is resistant to strong acids, strong bases, and common oxidants and reducing agents. For example, methane, under normal conditions, does not react with strong acids, strong bases, and strong oxidants such as potassium permanganate solution. It only reacts with halogens when there is a special initiator at high temperature or light. In this compound, 5-alkane also exhibits such stability, providing a relatively stable carbon skeleton for the molecule, making the overall structure solid and difficult to change easily due to common external chemical reagents.
2-ene contains carbon-carbon double bonds, which are unsaturated structures with high electron cloud density and are vulnerable to electrophilic attack, triggering addition reactions. However, in this compound, its activity will be fine-tuned due to the power supply effect of 5-alkane and the conjugation effect of 3-alkyne. For example, propylene and bromine water can react rapidly at room temperature, and the 2-ene in this compound may have different reaction rates due to the influence of surrounding groups, but it still retains the basic addition activity of alkene bonds, but its stability is slightly higher than that of simple alkenyl compounds.
3-alkyne contains carbon-carbon triple bonds and is also unsaturated. Its π electron cloud is distributed in a cylindrical shape, with high electron fluidity, and can undergo various reactions such as electrophilic addition and nucleophilic addition. However, after forming a conjugated system with 2-ene, the electron cloud distribution is more uniform, reducing the local electron cloud density of the triple bond, resulting in a decrease in reaction activity and enhanced stability. For example, acetylene and water can be rapidly added under the catalysis of mercury salts, and the reaction conditions of 3-alkyne in this compound may be more severe, reflecting the characteristics of relative stability.
The coexistence of the three, the saturated stable structure of 5-alkane and the conjugation effect of 2-ene and 3-alkyne, together make the chemical properties of 5-alkane-2-ene-3-alkyne carboxylic acid in a specific stable state. In general common chemical environments, it is not easy to undergo intense reactions, and specific conditions are required to promote structural changes or chemical reactions.

To prepare 5-bromo-2-pentene-3-one, the following ancient methods can be used.
First, 2-pentene-3-one is used as the starting material to react with bromine under specific conditions. This reaction needs to be carried out at a low temperature and with a suitable solvent, such as in a dichloromethane solvent, cooled to about 0 ° C, and bromine is slowly added dropwise. The carbon-carbon double bond of 2-pentene-3-one is nucleophilic, and the bromine molecule is polarized under the action of the solvent. The positively charged bromine atom is attracted by the double bond and is first added to one end of the double bond to form a bromide ion intermediate. Subsequently, the bromine anion in the solution attacks the bromide ion from the other side to obtain 5-bromo-2-pentene-3-one. This process requires attention to the reaction temperature. If the temperature is too high, it is easy to form polybrominates and affect the purity of the product.
Second, it can be started with a suitable alcohol. First, the corresponding alcohol is oxidized to obtain 2-pentene-3-one. For example, 2-pentene-3-one can be obtained by oxidizing 2-pentene-3-alcohol as a raw material with a suitable oxidant, such as potassium dichromate-sulfuric acid system or PCC (chlorochromate pyridinium salt), under suitable conditions. After that, 5-bromo-2-pentene-3-one can be obtained by reacting with bromine as described above. When oxidizing with potassium dichromate-sulfuric acid system, the reaction conditions are relatively severe and need to be strictly controlled; while PCC oxidation conditions are relatively mild and have good selectivity to substrates.
Third, react with a brominating reagent with a conjugated diolefin. If a suitable conjugated diolefin is selected, it will react with a brominating reagent such as hydrogen bromide in the presence of a catalyst. The conjugated diolefin will undergo a 1,4-addition reaction, and bromine atoms are added at both ends of the conjugated system to form a product containing ethylenically bonds and bromine atoms. After appropriate oxidation steps, the allyl hydroxyl group is oxidized to carbonyl groups to obtain 5-bromo-2-pentene-3-one. This path requires clever design of the conjugated diolefin structure and selection of appropriate oxidation methods to achieve the preparation of the target product.

Since modern times, there have been many kinds of things in the market, and their prices have also changed from time to time and from place to place. As for the market price of 5-alkane-2-ene-3-heptanoic acid, it is difficult to determine.
This compound is not a common product in daily life, and its price depends on various reasons. First, its preparation is difficult and easy. If the preparation method is difficult, requires exquisite techniques, rare materials, and takes a long time and has low yield, its price will be high. Like the ancient alchemy, if you want to obtain gold and silver, you have to work hard, and you get very little, your price is naturally high. On the contrary, if the preparation is simple, and the required things are ordinary, the price may be close to the people.
Second, the state of supply and demand is also the main reason. If you work in research, the demand for this thing is thirsty, and the supply in the market is very small, like the hope of a drought, the price will inevitably increase. In the past, among the good horses in the Western Regions, there were many people who wanted it, but the number was limited, so the price was extremely expensive. If the supply exceeds the demand, the rivers will flood, and the price will drop.
Furthermore, the difference between time and place also affects the price. At that time and place, or for various reasons, this thing is very precious; at this time and here, or for other reasons, its price is flat. If lychee was born in Lingnan, the local price is cheap, but it is shipped to the north. Due to the long journey, it is difficult to keep it fresh, and its price is doubled.
To sum up, in order to know the confirmed price of 5-alkane-2-ene-3-heptanoic acid in the market, it is necessary to carefully examine the preparation situation, the difference in supply and demand, etc., before we can get a more accurate theory. However, at this moment, it is difficult to directly state the geometry of its price.