3-Chloro-5-methylpyridine

3-Bromo-5-methylpyridine is a crucial intermediate in organic synthesis, which is widely used in many fields and has great value.
In the field of medicinal chemistry, it is often used as a key structural unit to construct a variety of drug molecules. Due to the unique chemical properties of the pyridine ring with bromine atoms and methyl groups, it can endow drugs with specific biological activities and pharmacological functions. For example, by structural modification and derivatization of 3-bromo-5-methylpyridine, drugs with antibacterial, anti-inflammatory, and anti-tumor activities can be prepared. In the development of some new antimicrobial drugs, 3-bromo-5-methylpyridine is used as the starting material, and various active groups are introduced through multi-step reactions to improve the inhibitory effect of drugs on specific pathogens.
It also plays an important role in the field of materials science. It can be used to synthesize functional materials, such as organic optoelectronic materials. The conjugated structure of the pyridine ring and the properties of the substituent can adjust the electronic transport properties and optical properties of the material. Some organic semiconductor materials synthesized based on 3-bromo-5-methylpyridine exhibit excellent properties in organic Light Emitting Diode (OLED) and organic solar cells, which can improve the luminous efficiency and energy conversion efficiency of the devices.
In the field of pesticide chemistry, 3-bromo-5-methylpyridine can be used as an important intermediate for the synthesis of high-efficiency pesticides. Through rational design and modification, pesticide products with high selectivity and low toxicity can be prepared. For example, some new insecticides use it as a raw material to build core structures, which have significant killing effects on specific pests, and have little impact on the environment and non-target organisms, which is conducive to the sustainable development of agriculture.
Furthermore, in organic synthetic chemistry, 3-bromo-5-methyl pyridine can undergo a variety of chemical reactions due to the activity of bromine atoms, such as nucleophilic substitution reactions, coupling reactions, etc. Therefore, different functional groups can be conveniently introduced to construct complex organic compounds, providing organic synthetic chemists with rich synthesis strategies and means to help the creation and development of new organic compounds.

3-Deuterium-5-methylpyridine is an organic compound. Although there is no such exact record in the context of Tiangongkai, its physical properties can be inferred in traditional classical language according to its chemical composition and the properties of similar compounds.
The appearance of this compound may be a colorless to light yellow liquid, with a special odor. Due to the nitrogen heterocycle and methyl and deuterium atoms, its structure is unique and different from common hydrocarbons. Its odor may be irritating. At room temperature and pressure, the boiling point and melting point have specific values due to the force between molecules. Due to the influence of molecular polarity, its solubility in water is limited, and it is more soluble in organic solvents, such as ethanol, ether, etc. This is due to the principle of "similar miscibility". The force between the organic solvent and the compound is similar, which is conducive to mutual solubility.
Its density is lighter than that of water, and it can float on the water surface when placed in water. And because it contains deuterium atoms, some physical properties are slightly different from those of similar compounds composed of ordinary hydrogen atoms. The mass of deuterium atoms is greater than that of hydrogen atoms, resulting in an increase in its molecular weight, or a subtle effect on the melting point, boiling point, and density, such as the boiling point or slightly higher than the corresponding hydrogen-containing compounds.
Furthermore, the stability of 3-deuterium-5-methylpyridine may be affected by its structure. The pyridine ring has certain aromatic properties, which makes its structure relatively stable. The existence of methyl groups may have a fine-tuning effect on its chemical activity, and deuterium atoms replace hydrogen atoms. In some chemical reactions, the reaction rates may vary due to the different dissociation energies of deuterium-carbon bonds and hydrogen-carbon bonds. In general, the physical properties of this compound are determined by its unique chemical structure, and it may have specific uses and significance in organic synthesis, chemical research and other fields.

3-Bromo-5-methylpyridine, the stability of this product is acceptable. The reason for its stability is that the pyridine ring is aromatic and the system energy is low, which is the basis for structural stability. Bromine and methyl are attached to the pyridine ring, although it will affect the distribution of the electron cloud of the ring, it has not greatly damaged its inherent stability.
From the perspective of bond energy, the bond energy of C-Br bond and C-C bond (where methyl is connected to the pyridine ring) is relatively considerable, and high energy is required to break it. Under normal temperatures and common chemical environments, it is not easy to spontaneously occur bond fracture-induced structural changes.
However, its stability is not absolute. In case of strong oxidants, the methyl groups on the pyridine ring can be oxidized to form oxidation products such as carboxyl groups. And in case of strong nucleophilic reagents, the C-Br bond can undergo nucleophilic substitution reaction, and the bromine atom is replaced by a nucleophilic group.
However, under conventional conditions, such as room temperature and pressure, without the action of special chemical reagents, 3-bromo-5-methyl pyridine can maintain a relatively stable state and can be stored for a certain period of time without significant chemical changes.

To prepare 3-bromo-5-methylpyridine, the methods are as follows:
First, 5-methylpyridine is used as the starting material and obtained by bromination. In this reaction, the pyridine ring of 5-methylpyridine has an electron-absorbing property on the nitrogen atom, resulting in uneven electron cloud density of the pyridine ring, and the electron cloud density of the β position is relatively high, which is easier to be attacked by the bromine atom. When a suitable brominating agent, such as liquid bromine, is used with the help of a suitable catalyst, such as iron tribromide, at a suitable temperature and reaction time, bromine atoms can replace hydrogen atoms at the β position of 5-methylpyridine to obtain 3-bromo-5-methylpyridine. However, this reaction, or other brominated products are formed, requires fine control of the reaction conditions to improve the yield of the target product.
Second, it can be prepared by constructing a pyridine ring. For example, with a suitable nitrogen-containing and carbon-containing raw material, a pyridine ring is formed through a multi-step reaction, and methyl and bromine atoms are introduced at the same time. Pyridine derivatives can be obtained by condensation cyclization of 1,5-dicarbonyl compounds with ammonia or amines under suitable conditions. Subsequently, according to needs, by halogenation, alkylation and other reactions, bromine atoms and methyl groups are introduced at specific positions in the pyridine ring. Although this path is a little complicated, it can precisely control the position and type of substituents on the pyridine ring, which is beneficial to improve the purity and yield of the target product.
Third, it can be achieved by means of palladium-catalyzed coupling reaction. First prepare pyridine derivatives containing specific substituents, such as 5-methyl pyridine boronic acid or its esters, and prepare halogenated compounds containing bromine atoms. In the presence of a palladium catalyst, such as tetra (triphenylphosphine) palladium (0), and a base, the two coupling reactions occur to form carbon-carbon bonds or carbon-hetero bonds to obtain 3-bromo-5-methylpyridine. This method has good selectivity and mild conditions, and is widely used in the field of organic synthesis.

The price of 3-bromo-5-methylpyridine in the market is difficult to determine. The price of the product often changes due to various reasons, such as the trend of supply and demand, the difficulty of making it, the high and low quality, and the competition of the market.
If there is supply and demand, there are many people who need it and there are few people who supply it, the price will rise; on the contrary, if the supply exceeds the demand, the price will fall. The difficulty and ease of making it are also heavy. If the production requires complex methods, high technology, time-consuming and expensive, the price will also be high. The high and low quality is related to the price, and the price of those who are of high quality is often higher than that of those who are of poor quality. The competition in the market is also the main reason, and the price of the competition may be leveled to compete for customers.
Looking at the example of various markets, the price of such chemical products is between tens and hundreds of gold per gram. However, this is only an approximate number, and the actual price may vary from time to time and from city to city. To know the exact price, you can consult the merchant of chemical materials, or check the net of chemical trading, so that you can get the current price as a reference.