2-Fluoropyridine-5-boronic acid

2-% hydroxypropionic acid-5-succinic acid, both of which are widely used.
2-hydroxypropionic acid, also known as lactic acid. In the food industry, it is an important sour agent, which can give food a unique flavor. It is often added to various beverages and candies, and can also be used as a preservative. With its acidity, it can inhibit the growth of microorganisms and prolong the shelf life of food. In the field of medicine, it can be used to manufacture drug sustained-release preparations. Because of its good biocompatibility and degradability, it can control the release rate of drugs and improve the efficacy of drugs. In the chemical industry, it is a raw material for synthesizing a variety of polymer materials. The resulting polylactic acid plastic has good biodegradability and is widely used in packaging materials, disposable tableware, etc., which can alleviate the problem of white pollution.
5-succinic acid, in the food industry, can be used as a sour taste regulator to optimize the taste and flavor of food, and is also an important raw material for food flavor synthesis. In medicine, it has a regulatory effect on human metabolism and can assist in the treatment of some metabolic disorders related diseases. In the field of biochemistry, it is a key intermediate product for microbial fermentation to produce a variety of high value-added products. After specific microbial fermentation processes, it can be converted into important chemical products such as succinic anhydride and 1,4-butanediol. These products are widely used in plastics, fibers, coatings and other industries. In conclusion, 2-hydroxypropionic acid and 5-succinic acid play an indispensable role in many fields such as food, medicine, and chemical industry, and are of great significance to promoting the development of various industries.

To prepare 2-hydroxy-5-chlorobenzoic acid, the following method can be used.
First take the appropriate raw material, start with m-chlorotoluene, and convert the methyl group to the carboxyl group by oxidation. To achieve this step, a strong oxidant, such as potassium permanganate ($KMnO_ {4} $), is often used under appropriate reaction conditions, such as heating, in an alkaline environment, the methyl group in m-chlorotoluene is oxidized to obtain m-chlorobenzoic acid. During this process, the valence state of manganese in potassium permanganate decreases, and the valence state of methyl-carbon in m-chlorotoluene increases, resulting in a redox reaction.
The obtained m-chlorobenzoic acid is followed by a step of hydroxylation. Aromatic ring electrophilic substitution reaction can be used to introduce a sulfonic acid group using concentrated sulfuric acid and fuming sulfuric acid as the medium. This sulfonic acid group can be positioned, so that subsequent hydroxylation is more likely to occur at a specific position. Then by alkali melting, the sulfonic acid group is converted into a hydroxyl group. Specifically, a strong base such as sodium hydroxide is co-melted with a compound containing a sulfonic acid group, and the sulfonic acid group is replaced by a hydroxyl group to obtain the target product 2-hydroxy-5-chlorobenzoic acid.
Or another way is found to use p-chlorophenol as the starting material. The carboxylation reaction of p-chlorophenol can be carried out first. Similar to the Kolbe-Schmidt reaction, under appropriate conditions, such as at high temperature and pressure, carbon dioxide is used as the carboxylation reagent, and in an alkaline environment, the ortho-position of the phenolic hydroxyl group is introduced into the carboxyl group, so 2-hydroxy-5-chlorobenzoic acid can also be obtained. In this reaction, carbon dioxide provides a carboxyl group, and the ortho-position of the phenolic hydroxyl group becomes the check point of the reaction activity. The carboxylation is completed, and the desired 2-hydroxy-5-chlorobenzoic acid is finally obtained.

2-%E6%B0%9F%E5%90%A1%E5%95%B6-5-%E7%A1%BC%E9%85%B8, its scientific name is sodium metaaluminate ($NaAlO_2 $), and the following are its physical properties:
Sodium metaaluminate is a white crystalline powder, odorless, easily soluble in water, insoluble in ethanol, and its aqueous solution is alkaline. It easily absorbs moisture and carbon dioxide in the air, and gradually generates aluminum hydroxide.
Looking at its shape, sodium metaaluminate is a solid, white and fine, like powder. If placed in the air, it can be seen to change after a while, and other substances gradually emerge due to the absorption of water vapor and carbon dioxide in the air. When it dissolves in water, it quietly disappears and disappears without a trace, but the nature of water gradually changes, showing an alkaline state. Although this alkalinity is not as strong as caustic alkali, it should not be ignored. And it is not soluble in ethanol. The coexistence of the two is distinct, which shows that it is very different from ethanol.
Sodium metaaluminate is widely used in many industrial fields. Due to its special physical properties, it has important applications in textile, paper and other industries. For example, in the textile industry, it can be used as an auxiliary to help fabrics dye evenly; in the papermaking industry, it can improve paper properties. Understanding the physical properties of sodium metaaluminate is of great significance for its correct use and in-depth research, and also helps to expand its application in more fields, providing assistance for industrial production and scientific research.

2-%E6%B0%9F%E5%90%A1%E5%95%B6-5-%E7%A1%BC%E9%85%B8, that is, phosphoric acid, which is a medium-strong dibasic acid. It has the following chemical properties:
First, acidic. Phosphoric acid can ionize in water, release hydrogen ions, exhibit acidity, and can neutralize with bases. For example, when reacted with sodium hydroxide, sodium phosphite and water are formed: $H_3PO_3 + 2NaOH = Na_2HPO_3 + 2H_2O $. In this reaction, two hydrogen ions of phosphoric acid combine with hydroxide ions in sodium hydroxide to form water to form sodium phosphite.
Second, reductivity. The valence of phosphorus in phosphoric acid is + 3, which is in the intermediate valence state, so it has reductivity. It can be oxidized by strong oxidants, such as reacting with hydrogen peroxide, phosphorus will be oxidized to + 5 valence, resulting in phosphoric acid: $H_3PO_3 + H_2O_2 = H_3PO_4 + H_2O $. In this reaction, hydrogen peroxide acts as an oxidant to oxidize phosphoric acid to phosphoric acid.
Third, it is decomposed by heat. Phosphoric acid decomposes when heated, resulting in phosphine and phosphoric acid: $4H_3PO_3\ xlongequal {\ Delta} 3H_3PO_4 + PH_3 ↑ $. In this reaction, phosphoric acid itself disproportionates, some phosphorus elements increase in valence to form phosphoric acid, and some phosphorus elements decrease in valence to form phosphine.
Fourth, esterification reaction. Phosphoric acid, as an acid, can be esterified with alcohols. For example, the reaction with ethanol, under the condition of concentrated sulfuric acid catalysis and heating, generates diethyl phosphite and water: $H_3PO_3 + 2C_2H_5OH\ xrightleftharpoons [{\ Delta}] {{concentrated sulfuric acid}} (C_2H_5O) _2HPO + 2H_2O $. This reaction follows the general law of esterification reaction, acid dehydrogenation of hydroxyl alcohol, and the corresponding ester and water are formed.

When storing and transporting borax, there are several things to pay attention to.
First and foremost, moisture-proof is essential. Borax is easy to absorb moisture, and if it encounters moisture, it is easy to agglomerate and damage its quality. Therefore, when storing, it should be placed in a dry and ventilated place, away from a dark and humid place. And the storage devices used should also be well sealed to prevent moisture from invading.
Second, heat protection should not be ignored. Under high temperature, borax or biochemical reactions cause its properties to change. During transportation, do not expose borax to the hot sun or near high temperature heat sources. Vehicle shipping should be properly insulated to keep it at a suitable temperature.
Furthermore, anti-pollution is of paramount importance. If borax is mixed with other chemicals and impurities, it will affect its purity and performance. The storage place should be clean and free of filth, and isolated from other things. The container for transportation must also be clean. After strict cleaning and drying, borax can be contained before impurities can be mixed in.
In addition, when handling, handle it with care. Borax is brittle, and if it is subject to severe vibration or collision, it is easy to break, which not only damages its shape, but also affects its quality. Handlers must operate carefully and use appropriate tools to keep the borax intact.
In general, the storage and transportation of borax, moisture, heat, pollution, vibration, and other matters must be carefully attended to in order to maintain the quality of borax for future use.