1H-Pyrrole-2-carboxaldehyde, 1-(2-chlorophenyl)-

1H-pyrrole-2-formaldehyde, 1- (2-chlorophenyl), the chemical structure of this compound is as follows. Its core is a pyrrole ring, which is a five-membered nitrogen-containing heterocycle with a unique conjugated structure, endowing the compound with specific electronic properties and reactivity. At the second position of the pyrrole ring, it is connected to an aldehyde group (-CHO). The aldehyde group is a functional group with high reactivity and can participate in many organic reactions, such as oxidation, reduction, condensation, etc., which has a great impact on the chemical properties and synthetic applications of the compound.
At the first position of the pyrrole ring, there is a 2-chlorophenyl group connected. The phenyl group is an aromatic group, which imparts certain stability and hydrophobicity to the compound. And the second position of the phenyl group is connected with a chlorine atom, and the electronegativity of the chlorine atom is relatively large. It can affect the electron cloud distribution of the benzene ring and the whole molecule through induction effects, and then affect the physical and chemical properties of the compound, such as solubility and reaction selectivity.
The unique combination of this chemical structure makes the compound have special physical and chemical properties, which may have potential application value in organic synthesis, medicinal chemistry, materials science and other fields. It can be used as a key intermediate to participate in the construction of many complex organic molecules.

1 - (2 -chlorophenyl) -1H -pyrrole-2 -formaldehyde, this material has many physical properties. Its properties may be crystalline solids, often in the form of white to light yellow powder, which is determined by the arrangement and interaction of atoms in its molecular structure. In terms of melting point, it is about [specific value] ° C, because the intermolecular forces can be overcome at a specific temperature, and the lattice structure is damaged and the state is transformed.
Solubility, slightly soluble in water. Because its molecules contain hydrophobic benzene and pyrrole rings, only the aldehyde group has a certain hydrophilicity, and the overall interaction with water molecules is weak, so it is difficult to dissolve. However, it has good solubility in organic solvents such as dichloromethane, chloroform, and tetrahydrofuran, because these solvents and the compound can form similar intermolecular forces, which is in line with the principle of "similar phase dissolution".
The compound is volatile to a certain extent, and a small amount of molecules can obtain enough energy to escape from the solid surface at room temperature and pressure. Its vapor pressure is relatively low, indicating that the intermolecular forces are strong and it is not easy to evaporate a lot.
In terms of stability, it is relatively stable under general conditions. However, due to the activity of aldehyde groups, when encountering specific chemicals such as strong oxidants and strong bases, it is prone to reaction-induced structural changes. Light and high temperature environments may also affect its stability, or trigger reactions such as intramolecular rearrangement and oxidation. This is due to the distribution of electron clouds on the aldehyde group and pyrrole ring in its molecular structure, which makes it sensitive to specific conditions.

1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde is commonly used in many organic synthesis reactions. It often appears in nucleophilic substitution reactions because its aldehyde group is electrophilic and vulnerable to attack by nucleophilic reagents. Reagents such as those with nucleophilic atoms such as nitrogen and oxygen can be derived from nucleophilic addition reactions, which are of great significance for the construction of complex organic structures.
It also plays a key role in condensation reactions. Condensation can occur with compounds with active hydrogen, such as some carbonyl compounds containing alpha-hydrogen, to form conjugated system products, which are widely used in the fields of materials science and medicinal chemistry, such as the synthesis of materials with specific optical and electrical properties, or as potential pharmaceutically active ingredients.
In addition, in redox reactions, 1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde is also involved. The aldehyde group can be oxidized into a carboxyl group, or reduced to an alcohol hydroxyl group under suitable reduction conditions, thereby expanding the functional group species of the compound, enriching the organic synthesis path, and then meeting the needs of different fields for specific structures and properties of organic compounds. It plays an important role in the development process of modern organic synthetic chemistry.

The preparation method of 1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde is not directly described in the classic "Tiangong Kaiwu", but it can be deduced by chemical methods.
First, use 2-chlorophenyl as the starting material. First, it is added to ethyl acrylate to obtain N- (2-chlorophenyl) -3-ethoxypropionamide. This step needs to be catalyzed in a suitable solvent with a mild catalyst, and the temperature is controlled in a moderate range to make the reaction proceed smoothly. Then, the obtained product is cyclized under alkaline conditions to form 1- (2-chlorophenyl) -1H-pyrrole-2-carboxylic acid ethyl ester. After hydrolysis, the ester group is changed to a carboxyl group. Finally, a suitable reducing agent, such as lithium aluminum hydride, is used to reduce the carboxyl group to an aldehyde group at a low temperature and in an anhydrous and oxygen-free environment to obtain 1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde.
Second, it can be started from 2-chloroacetophenone. First, it undergoes a Vilsmeier-Haack similar reaction with formamide under the action of a strong base. Using phosphorus oxychloride as activator, the corresponding imine salt intermediate is generated. Then, after hydrolysis, the imine is converted into an aldehyde group, and at the same time, the pyrrole ring is rearranged within the molecule to obtain the target product 1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde. This process requires precise control of the reaction conditions. After each step of the reaction, it is appropriate to purify the product by extraction, column chromatography and other means to obtain a pure product.

1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde has a wide range of uses. In the field of pharmaceutical research and development, it is often a key intermediate for the synthesis of new drugs. Through delicate chemical reactions, it can be ingeniously converted into compounds with unique pharmacological activities, making great contributions to the treatment and research of specific diseases.
In the field of materials science, 1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde also has unique applications. It can participate in the construction of materials with special photoelectric properties, contributing to the development of cutting-edge technologies such as Light Organic Emitting Diode and solar cells. Due to its unique structure, it can endow materials with unique optical and electrical properties, which greatly enhances their properties.
In the field of organic synthetic chemistry, it is an important cornerstone. With its active groups, it can react with a wide range of reagents and derive a wide variety of organic compounds. Organic chemists use this to expand the diversity of molecular structures, providing the possibility to explore new chemical substances and reaction pathways. In short, 1- (2-chlorophenyl) -1H-pyrrole-2-formaldehyde plays an indispensable role in many important fields and has a profound impact on the progress of science and technology.