3-Pyridinecarboxylic acid, 6-bromo-

6-Hydroxy-3-pentenoic acid is an organic compound with many unique chemical properties.
The first word about its acidity is that this compound contains a carboxyl group (-COOH), and the hydrogen atom in the carboxyl group is easier to dissociate, making the substance acidic. In aqueous solution, hydrogen ions (H 🥰) can be partially ionized, which can neutralize with bases. In case of sodium hydroxide (NaOH), the corresponding salt and water will be formed. The reaction equation is: 6-hydroxy- 3-pentenoic acid + NaOH → 6-hydroxy- 3-pentenoic acid sodium + H2O O. < Br >
Discuss the properties of its hydroxyl group (-OH). Hydroxyl groups are active and can participate in a variety of reactions. One is esterification. When combined with alcohols under acid-catalyzed conditions, the hydrogen atom in the hydroxyl group combines with the hydroxyl group in the alcohol to remove a molecule of water to form an ester compound. Second, the hydroxyl group is easily oxidized. If it encounters a strong oxidant, it can be oxidized to an aldehyde group or a carboxyl group. If the oxidant is mild, the hydroxyl group may be oxidized to a carbonyl group.
Furthermore, the compound contains carbon-carbon double bonds (C = C). The carbon-carbon double bonds are rich in electrons and have high reactivity. It is prone to addition reactions. For example, under the action of a catalyst with hydrogen (H _ 2), the double bond is opened, and hydrogen atoms are added to the double-bonded carbon atoms to generate saturated 6-hydroxyvaleric acid; with halogen elemental substances (such as Br _ 2), addition can occur, causing bromine water to fade; it can also undergo addition reactions with hydrogen halide (such as HCl). According to Markov's rule, hydrogen atoms are added to double-bonded carbon atoms containing more hydrogen.
In addition, 6-hydroxy- 3-pentenoic acid can undergo intramolecular reactions due to the presence of multiple functional groups. For example, hydroxyl groups and carboxyl groups can undergo molecular lactonation to form cyclic lactone compounds. And because there are multiple reactive check points in its structure, it can be used as an important organic synthesis intermediate for the preparation of more complex organic compounds.

What are the main uses of 6-3-4-1-1-1-1-2-1-2-1-2-1-2-1-2-1-2-1-2-2-2-2-2-2-3-2-2-3-2-2-3-2-3-2-2-3-2-2-3-3-3-2-2-3-3-2-3-3-2-3-3-3-3-3-3-3-2-3-3-3-3-3-3-3-3-3-3-3-3-4-3-3-3-3-3-3-3-3-3-3-3-3-3-3-3-4. 2. 2) 2. 2) 2. 2) 2) 2. 2) 2) 2. 2) 2. 2) 2. 2) 2. 2) 2. 2) 2. 2) 2. It can also be used in the synthesis of vinyl acetate, which is a raw material for polyvinyl alcohol, vinyl alcohol, etc., and vinyl can be used in the production process, which is indispensable in the production of clothing and so on.
Third, the production process is also not acetic acid. Acetic acid can be used in the synthesis of multiple compounds, such as aspirin, acetic acid is one of the important raw materials. It plays an important role in the synthesis of plastics, helping the effect of plastics.
Fourth, in the printing and dyeing process, acetic acid can be used as a dyeing aid. It can make the dye better adsorbed on the dye, improve the dyeing effect, make the color more uniform and uniform, and the dyeing fastness is better, so that the finished product of printing and dyeing can be improved.
Therefore, 6-3-acetate has important uses in food, chemical industry, printing and dyeing, etc., which has a profound impact on people's daily life and work.

To prepare 6-bromo-3-pentenoic acid, the following method can be used.
First take the pentene, and use an appropriate brominating agent, such as liquid bromine, under the conditions of light or peroxide initiation, carry out a free radical substitution reaction. The hydrogen on the double bond α-carbon of the pentene has high activity due to the double bond conjugation effect, and the bromine atom easily replaces the hydrogen at this position to obtain 3-bromo-1-pentene.
Then, hydroformylation of 3-bromo-1-pentene with carbon monoxide and water under suitable catalysts, such as palladium-containing complexes, under suitable temperature and pressure conditions, can make the double bond, carbon monoxide and water are added, and an aldehyde group is introduced at the end of the double bond to obtain 3-bromo-pentanal.
Then 3-bromo-pentanal is oxidized with a suitable oxidant, such as a mild silver ammonia solution or a new copper hydroxide suspension, and the aldehyde group is oxidized to a carboxyl group to obtain 6-bromo-3-pentanoic acid.
Another way is to make pentene react with N-bromosuccinimide (NBS) at the allyl position under the action of an initiator to directly obtain 3-bromo-1-pentene. The subsequent steps are the same as above, that is, through hydroformylation and oxidation, 3-bromo-pentanal and 6-bromo-3-pentanoic acid are obtained in sequence.
During the preparation process, the reaction conditions of each step need to be precisely adjusted, such as temperature, pressure, catalyst dosage, etc., to ensure that the reaction proceeds in the desired direction and improve the yield and purity of the product.

6-Hydroxy-3-pentenoic acid should be stored and transported with due attention to its chemical properties, safety considerations, and environmental impact.
This acid has specific chemical activity. Because it contains hydroxyl groups and alkenyl groups, it is prone to chemical reactions. When storing, the first thing to do is to choose a suitable container. Because it may react with some metals, such as iron and copper, it is appropriate to choose an inert material container such as glass and plastic to resist the chemical reaction between the capacitor and the acid to maintain the purity and stability of the acid.
Temperature and humidity are also critical. This acid is quite sensitive to changes in temperature and humidity. High temperature is easy to cause it to evaporate or accelerate decomposition, and high humidity environment may promote its hydrolysis. Therefore, it should be stored in a cool, dry place, and the temperature should be controlled within a specific range, generally 2-8 ° C is appropriate, and the humidity should be maintained at 40% -60%.
When transporting, safety protection is essential. 6-Hydroxy-3-pentenoic acid may be corrosive and irritating. Transportation personnel must be equipped with protective equipment, such as protective clothing, gloves, goggles, etc., to prevent acid from contacting the skin and eyes. And the transportation vehicle must be equipped with emergency treatment equipment, such as adsorbents, neutralizers, etc., in case of leakage.
Furthermore, this acid may have an impact on the environment. If leakage occurs during transportation, the acid will flow into the soil or water body, or cause environmental pollution. Therefore, when transporting, necessary anti-leakage measures should be taken, such as tight sealing of containers, vehicle anti-leakage devices, etc.
In addition, whether it is storage or transportation, it should follow relevant regulations and standards, and record storage and transportation information in detail, such as quantity, time, location, etc., in order to trace and manage, ensure the safety and compliance of the whole process, and avoid adverse effects on personnel and the environment.

6-Mercapto-3-pentenoic acid has an impact on both the environment and the human body.
In terms of the environment, if it is released in nature, it may cause water pollution. When it flows into rivers, lakes and seas, or is ingested by aquatic organisms, it causes accumulation in organisms. Its chemical properties may react with other substances in the water, change the chemical composition of the water body, and destroy the aquatic ecological balance. In the soil, it may affect the activity of soil microorganisms, interfere with the normal material circulation and nutrient transformation of the soil, and then affect plant growth.
As for the human body, 6-mercapto-3-pentenoic acid is potentially toxic. Inhaled through the respiratory tract, or irritates the mucosa of the respiratory tract, causing symptoms such as cough, asthma, and breathing difficulties. Long-term exposure may damage lung function. If it is exposed to the skin, it may cause skin allergies, redness, swelling, and itching. If taken by mistake, it will harm the digestive system and cause nausea, vomiting, abdominal pain, diarrhea, etc. And this substance may be genotoxic, interfering with the normal metabolism of human cells and the transmission of genetic information, and long-term exposure may increase the risk of cancer.
Therefore, the use, storage, and disposal of 6-mercapto-3-pentenoic acid should be used with caution to reduce its harm to the environment and human body.