methyl 5-nitropyridine-2-carboxylate

Methyl-5-nitropyridine-2-carboxylic acid ester, this is an organic compound. It has unique chemical properties and is widely used in the field of organic synthesis.
Looking at its structure, the pyridine ring is connected with methyl, nitro and carboxylic acid ester groups. Nitro has strong electron absorption, which can reduce the electron cloud density of the pyridine ring, making the electrophilic substitution reaction on the ring more difficult, but making the nucleophilic substitution reaction more likely. For example, when encountering nucleophilic reagents, the nitro-o and para-carbon atoms are vulnerable to attack and substitution reactions occur.
Methyl is the power supply group, which can change the electron cloud distribution of the pyridine ring to a certain extent and affect the reaction activity. In some reactions, it can increase the electron cloud density at a specific location, making it easier to react at that location.
The carboxylic acid ester group is active and can participate in a variety of reactions. During hydrolysis, under the catalysis of acid or base, 5-nitropyridine-2-carboxylic acid and methanol can be formed. The ester exchange reaction with alcohol can generate new ester compounds, whereby the molecular structure can be modified to meet different synthesis needs.
In addition, the compound may also participate in the reduction reaction, and the nitro group can be reduced to other functional groups such as amino groups, providing an important intermediate for the synthesis of nitrogen-containing compounds, which is of great significance in many fields such as drug synthesis and material preparation.

The common synthesis methods of methyl 5-nitropyridine-2-carboxylic acid esters generally include the following.
First, pyridine-2-carboxylic acid is used as the starting material. Shilling pyridine-2-carboxylic acid and methanol are esterified under the catalysis of concentrated sulfuric acid. This reaction requires heating to reflux, so that the carboxylic acid and alcohol can fully react to form pyridine-2-carboxylic acid methyl ester. Then, the pyridine-2-carboxylic acid methyl ester is placed in a mixed acid (concentrated sulfuric acid and concentrated nitric acid) system for nitrification. At a suitable temperature, nitrate is used as an electrophilic agent to attack the pyridine ring, and nitro is introduced at the 5-position to obtain methyl 5-nitropyridine-2-carboxylic acid ester. This method step is relatively clear, but the nitrification reaction conditions need to be carefully controlled to prevent side reactions.
Second, 5-nitropyridine is used as the starting material. First, 5-nitropyridine reacts with carbon dioxide under specific catalyst and pressure conditions, and a carboxyl group is introduced at the 2-position of the pyridine ring to generate 5-nitropyridine-2-carboxylic acid. Subsequently, 5-nitropyridine-2-carboxylic acid is esterified with methanol under acid catalysis to obtain methyl 5-nitropyridine-2-carboxylic acid ester. In this path, the carboxylation reaction conditions of carbon dioxide are stricter and the equipment requirements are quite high, but the side reactions such as polynitrogenation that may occur in the nitration reaction can be avoided.
Third, the palladium-catalyzed cross-coupling reaction strategy is adopted. Appropriate halopyridine derivatives and borate esters or boric acid derivatives containing carboxyl and nitro groups are used as raw materials. In the presence of palladium catalyst, ligand and base, cross-coupling reaction occurs to directly construct the substituent on the pyridine ring and form the target product methyl 5-nitropyridine-2-carboxylate. This method has the advantages of high reaction selectivity and relatively mild conditions, but the cost of palladium catalyst is high, which limits its large-scale application.

Methyl-5-nitropyridine-2-carboxylic acid ester, an organic compound, is useful in many fields.
In the field of pharmaceutical research and development, it is often a key intermediate. It can be converted into biologically active drug molecules through specific reaction steps. For example, for specific disease targets, chemically modified and modified, or new therapeutic drugs can be created, bringing hope for overcoming diseases.
In the field of materials science, it also has its own influence. With appropriate treatment, it may be able to impart specific properties to materials. For example, introducing it into polymer materials may change the electrical and optical properties of materials, thereby meeting the specific needs of electronic devices, optical materials and other fields.
In the field of pesticide chemistry, methyl-5-nitropyridine-2-carboxylic acid esters are also useful. With this as a starting material, high-efficiency, low-toxicity and environmentally friendly pesticide products can be developed. With its structural characteristics, it may exhibit unique inhibitory and killing effects on specific pests or pathogens, escorting agricultural harvests.
In organic synthetic chemistry, it is an important building block. Chemists can build more complex and diverse organic molecular structures through various organic reactions, such as nucleophilic substitution, oxidation and reduction, according to its structural characteristics, which promotes the continuous development of organic synthetic chemistry and expands the variety and application range of compounds.

Methyl 5-nitropyridine-2-carboxylic acid ester, the price range of this substance in the market is quite difficult to determine. The price often varies due to various reasons, such as the source of the material, the difficulty of preparation, and the supply and demand of the market.
In the past, if the material was easy to obtain, the preparation method was simple and familiar, and its price may tend to be flat. However, if the material is thin, the preparation process is complicated and difficult, and the price must rise. The supply and demand of the market are also the main reasons. Those who want it are many, and those who supply it are few, the price will be high; on the contrary, if the supply exceeds the demand, the price will drop.
According to the example of the past year, at ordinary times, the price may be between a few yuan and a few tens of yuan per gram. However, the market situation changes, if the material is short, or the preparation method changes, the price may change drastically. Or a sharp rise, up to more than 100 yuan per gram; or a sharp drop, to a few yuan per gram. Therefore, if you want to know the exact price, you should consult the firm specializing in this product, or check the recent market records, to obtain approval.

When preparing methyl 5-nitropyridine-2-carboxylate, there are many things to pay attention to.
First, the selection and treatment of raw materials is extremely critical. The starting materials used must have a high purity, and the presence of impurities or side reactions may cause clumps, resulting in poor product purity. Before use, the raw materials may need to be purified by recrystallization, distillation, etc., to ensure the smooth progress of the reaction.
Second, the control of the reaction conditions must not be lost. Temperature has a profound impact on the reaction. If the temperature is too high, or the reaction is out of control, many by-products are generated; if the temperature is too low, the reaction rate will be slow and take a long time. The appropriate reaction temperature should be precisely found according to the specific reaction mechanism, and strictly regulated with the help of temperature control equipment. The choice of reaction solvent is also very important, and the solubility of the reactants and products, as well as the influence on the reaction activity, need to consider the most suitable solvent system.
Third, the monitoring of the reaction process is indispensable. The reaction process can be monitored in real time by means of thin layer chromatography (TLC), high performance liquid chromatography (HPLC), etc., to gain insight into the consumption of raw materials and the formation of products. If the reaction is found not to advance as expected, the reaction conditions can be adjusted in time to avoid the risk of waste of raw materials and impurity of the product.
Fourth, the separation and purification of the product is very important. After the reaction is completed, the product is often mixed with unreacted raw materials, by-products and solvents. According to the physical and chemical properties of the product and impurities, appropriate separation methods, such as extraction, column chromatography, recrystallization, etc., should be selected to obtain high-purity products.
Fifth, safety issues must be kept in mind. The reagents used in the reaction may be toxic, corrosive, and flammable. Strictly follow safety procedures when operating, and wear appropriate protective equipment, such as gloves, goggles, and gas masks. Carry out the reaction in a well-ventilated environment, and properly dispose of waste reagents to prevent environmental pollution and safety accidents.