2-Pyridinecarboxylic acid, 6-chloro-, methyl ester

2-% pentenoic acid, 6-bromo-, and pentanitrile are mainly used as intermediates in organic synthesis. In the field of organic chemistry, these two are mostly starting materials or key intermediates for the preparation of complex organic compounds.
As far as 2-pentenoic acid is concerned, its chemical properties are active because it has two types of active functional groups, carbon-carbon double bonds and carboxyl groups, in the molecule. On the one hand, carbon-carbon double bonds can undergo addition reactions, such as addition to electrophilic reagents such as halogens and hydrogen halides, thereby introducing new functional groups and adding changes to the molecular structure; hydrogenation reactions with hydrogen under the action of suitable catalysts can be converted into saturated valeric acid, changing the unsaturation of the molecule and expanding its application scope. On the other hand, carboxyl groups can participate in esterification reactions, and alcohols can generate corresponding ester compounds under acid-catalyzed conditions. Esters are widely used in flavors, coatings and other industries to add unique aroma to products or improve coating performance.
6-bromo-pentanonitrile also has important uses. Cyanyl and bromine atoms are active check points. Cyanyl groups can be hydrolyzed to form carboxyl groups, which can be further converted into various carboxylic acid derivatives; amine groups can also be formed through reduction reactions to construct nitrogen-containing organic compounds, which are of great significance in the field of drug synthesis. Many drug molecular structures contain such groups. As a good leaving group, bromine atoms can undergo nucleophilic substitution reactions and react with a variety of nucleophilic reagents to achieve diverse modifications of molecules, such as reacting with sodium alcohol to generate corresponding ether compounds, or reacting with amines to prepare nitrogen-containing heterocyclic compounds, etc., to assist in the development of new organic materials and drugs.

2-% pentenoic acid, 6-brom-, pentanitrile, are all organic compounds. The physical properties of pentanitrile are as follows.
pentanitrile, at room temperature and pressure, is a colorless and transparent liquid with a special odor. Its boiling point is about 117 ° C. At this temperature, pentanitrile changes from liquid to gaseous. The melting point is about -96.2 ° C. When the temperature drops to Si, pentanitrile solidifies from liquid to solid. Because its molecular structure contains cyanyl (-CN), it has a certain polarity, so it has a certain solubility in water, but the solubility is not very high, and it can be miscible in any proportion with common organic solvents, such as ethanol, ether, acetone, etc. This is because it is similar to the principle of compatibility.
The density of pentanitrile is slightly smaller than that of water, about 0.794g/cm ³. If it is mixed with water, pentanitrile floats on the water. The vapor pressure of pentanitrile is low at room temperature, and the volatility is relatively weak. However, at higher temperatures or in poor ventilation, it can still evaporate in the air.
In addition, pentanitrile has certain chemical stability, but under specific conditions, such as strong acids, strong bases or high temperatures, the presence of catalysts, chemical reactions can occur. Its cyanide group can participate in a variety of organic synthesis reactions and is an important intermediate in organic synthesis. For example, in hydrolysis reactions, pentanitrile can be converted into valeric acid; in reduction reactions, it can be converted into pentylamine.

2-% hydroxypropionic acid, 6-brom-, and propionaldehyde are all organic compounds, each with unique chemical properties.
2-hydroxypropionic acid, commonly known as lactic acid. It is acidic, because the carboxyl group (-COOH) can partially ionize hydrogen ions, and can neutralize with bases, such as reacting with sodium hydroxide to form sodium lactate and water. Lactic acid has hydroxyl groups (-OH) and can undergo esterification reaction. It can form esters with alcohols catalyzed by concentrated sulfuric acid and heated. At the same time, because there are both hydroxyl and carboxyl groups in the molecule, intermolecular dehydration and polycondensation can occur to form polylactic acid, which is an important biodegradable material. < Br >
6-bromo- (seems to be incomplete information here, presumed to be an organic substance), if it is 6-bromohydrocarbon, because the bromine atom is a halogen atom, its properties are active. Substitution reaction can occur. Under the heating condition of sodium hydroxide aqueous solution, the bromine atom is replaced by hydroxyl group to form alcohol; under the heating condition of sodium hydroxide alcohol solution, an elimination reaction occurs to form an unsaturated bond. If the organic substance also contains other functional groups, such as carboxyl groups, hydroxyl groups, etc., it will also have corresponding functional group properties.
Propionaldehyde contains an aldehyde group (-CHO), which has strong reductivity. It can be oxidized by weak oxidants such as silver ammonia solution to produce silver elemental substance, ammonium propionate, ammonia gas and water; it can also be oxidized by new copper hydroxide suspensions to produce brick red cuprous oxide precipitation, propionic acid and water. Propionaldehyde can also undergo an addition reaction with hydrogen under catalyst and heating conditions, and the aldehyde group is reduced to a hydroxyl group to generate 1-propanol.

To prepare 2-pentenoic acid and 6-bromo-pentanal, the synthesis method is as follows:
First, the synthesis of 2-pentenoic acid. Diethyl malonate and 1-bromopropane can be used as starting materials. Diethyl malonate has active methylene. Under the action of strong bases such as sodium alcohol, the hydrogen of the methylene is taken away to form a carboanion. This carboanion has strong nucleophilicity and can undergo nucleophilic substitution reaction with 1-bromopropane. After alkylation, the product is hydrolyzed by alkali, then acidified and decarboxylated to obtain 2-pentenoic acid. This is a classic synthesis method of diethyl malonate. Using its reactive methylene properties, the desired carbon chain is introduced through a series of reactions, and then ingeniously decarboxylated to obtain the target product.
As for the synthesis of 6-bromo-valeraldehyde. It can be started from adipic acid, which is heated to undergo intramolecular dehydration and decarboxylation to generate cyclopentanone. Cyclopentanone is reduced to cyclopentanol, cyclopentanol reacts with hydrobromic acid under appropriate conditions, and the hydroxyl group is replaced by a bromine atom to generate bromocyclopentane. Bromocyclopentane is eliminated in a strong alkali alcohol solution to generate cyclopentene. Cyclopentene is oxidized by ozone and then reduced and hydrolyzed by zinc powder, which can break the double bond to form 6-bromo-pentanal. This route is converted in multiple steps, and various reactions are cleverly used to gradually construct the structure of the target molecule.
In this way, 2-pentanoic acid and 6-bromo-pentanal can be synthesized by the above method. Each step requires precise control of the reaction conditions to ensure the smooth progress of the reaction and the purity and yield of the product.

2-% glutaric acid, 6-bromo-, valeronitrile in storage and transportation, be sure to pay attention to the following things:
One, related to storage. Both should be stored in a cool, dry and well-ventilated place. Because glutaric acid and valeronitrile are prone to change their properties when heated, if the environment is humid, or cause a chemical reaction, causing them to deteriorate. Be sure to keep away from fire and heat sources to prevent the risk of fire and explosion. Both of these have certain chemical activity. In case of open flame, hot topic or flammable, valeronitrile is a flammable liquid, so fireworks are strictly prohibited in storage sites. It needs to be stored separately from oxidizing agents, acids, bases, etc., and must not be mixed. Glutaric acid is acidic, and contact with alkalis can cause a neutralizing reaction; valonitrile is chemically active, and contact with oxidants or cause violent reactions, and even explosions. Suitable materials should be prepared to contain leaks to prevent accidental leakage, and can be properly handled in time to avoid polluting the environment and causing greater harm.
Second, about transportation. Before transportation, be sure to ensure that the packaging is complete and well sealed. Glutaric acid and valonitrile are both corrosive and toxic. If the packaging is damaged, it may leak or corrode the means of transportation, endangering the safety of transportation personnel and may also pollute the surrounding environment. During transportation, ensure that the container does not leak, collapse, fall, or damage. It is necessary to drive strictly according to the specified route, and do not stop in densely populated areas and traffic arteries. Because of its potential danger, once an accident occurs in a crowded place or transportation hub, the consequences are unimaginable. Transportation vehicles should be equipped with the corresponding variety and quantity of fire-fighting equipment and leakage emergency treatment equipment. In the event of leakage, fire and other emergencies, emergency treatment can be carried out in a timely manner to reduce the degree of harm. Transportation personnel also need to be professionally trained, familiar with the dangerous characteristics and emergency treatment methods of the transported goods, operate cautiously during transportation, and always pay attention to the status of the goods.