What are the physical properties of 1-brom-2-iodobenzene?
1-Brom-2-iodobenzene, Chinese name 1-bromo-2-iodobenzene, is an organic compound. Its physical properties are as follows:
1. ** Physical state and color **: Under normal conditions, 1-bromo-2-iodobenzene is colorless to light yellow liquid. Looking at its morphology, it flows and has the characteristics of a liquid, and can flow freely in a container. As for the color, the range of colorless to light yellow reflects its purity and structural characteristics. This color characteristic is often shared by this class of halogenated aromatic compounds.
2. ** Odor **: This compound has a special aromatic odor. This odor originates from the structure of the benzene ring, and the conjugated system of the benzene ring endows it with unique volatility and odor characteristics. However, its odor is also affected by bromine and iodine atoms. The presence of halogen atoms makes the odor slightly change on the basis of ordinary aromatic odors, and has the special smell of halogens.
3. ** Melting boiling point **: The melting point is about -11 ° C, and the boiling point is about 256-258 ° C. The lower melting point indicates that the intermolecular force is relatively weak, and it can be converted from a solid state to a liquid state at a slightly higher temperature than the common low temperature environment. The higher boiling point is due to the stability of the benzene ring and the introduction of bromine and iodine atoms, which increases the molecular mass and enhances the intermolecular force. Higher energy is required to transform it from a liquid state to a gas state ** Density **: The density is greater than that of water, about 2.32 g/cm ³. This is due to the relatively large atomic mass of bromine and iodine atoms, resulting in an increase in the mass per unit volume of 1-bromo-2-iodobenzene, which will sink to the bottom when mixed with water.
5. ** Solubility **: 1-bromo-2-iodobenzene is insoluble in water. This is because water is a polar molecule, and the benzene ring in 1-bromo-2-iodobenzene is the main body of the non-polar structure. Although bromine and iodine atoms have a certain polarity, it is not enough to change the non-polar nature of the whole molecule. According to the principle of "similarity and miscibility", However, it is soluble in a variety of organic solvents, such as ethanol, ether, chloroform, etc. These organic solvents are mostly non-polar or weakly polar, and are similar to the intermolecular forces of 1-bromo-2-iodobenzene, so they are mutually soluble.
6. ** Volatility **: 1-bromo-2-iodobenzene has certain volatility. Although the volatility is not as high as that of small molecule compounds due to large molecular weight and intermolecular force limitations, some molecules still escape from the liquid surface and enter the gas phase at room temperature and pressure. Its volatility is also affected by environmental factors such as temperature and pressure. The increase in temperature and the decrease in pressure will increase the volatility.
What are the chemical properties of 1-brom-2-iodobenzene?
1-Bromo-2-iodobenzene, this is an organic compound with many unique chemical properties.
The first is the nucleophilic substitution reaction. Because of the two halogen atoms of bromine and iodine attached to the benzene ring, the halogen atom can be replaced by a nucleophilic reagent. If sodium alcohol is used as the nucleophilic reagent, under suitable conditions, bromine or iodine can be replaced by an alkoxy group to obtain the corresponding phenyl ether compound. In this reaction process, the nucleophilic reagent attacks the carbon atom connected to the halogen atom, and the halogen atom leaves with a pair of electrons to form a new carbon-heteroatomic bond.
On the electrophilic substitution reaction again. Although there are blunt groups caused by bromine and iodine Because the halogen atom has a lone pair of electrons, it can be conjugated with the benzene ring, resulting in a relatively high electron cloud density of the benzene ring ortho and para-site. For example, in the reaction with bromine catalyzed by iron bromide, bromine positive ions tend to attack the ortho and para-site of the benzene ring to form dihalogenated benzene derivatives.
There is also a metal-organic reaction. 1-Bromo-2-iodobenzene can react with metal magnesium to form Grignard reagents. Grignard reagents are extremely active and can react with a variety of carbonyl-containing compounds, such as aldose, ketone, etc., through addition and hydrolysis steps to obtain alcohols, which are important means of carbonization in organic synthesis.
In addition, Under the action of metal catalysts such as palladium, it can be coupled with other halogenated hydrocarbons or olefins to form carbon-carbon bonds, which are used to synthesize complex organic molecules and are widely used in the fields of drug synthesis and materials science.
In short, 1-bromo-2-iodobenzene bromide and iodine atoms exist, have rich chemical properties, and occupy an important position in organic synthesis chemistry. They are key raw materials and intermediates for the preparation of various organic compounds.
What are the applications of 1-brom-2-iodobenzene in organic synthesis?
1-Bromo-2-iodobenzene has a wide range of uses in the field of organic synthesis. First, it can be used to prepare various benzene derivatives. Through palladium-catalyzed coupling reactions, such as Suzuki coupling and Stille coupling, it can be coupled with boron, tin and other compounds to form carbon-carbon bonds and derive benzene series compounds with diverse structures, which are of great significance in pharmaceutical chemistry and materials science. < Br >
Furthermore, through the nucleophilic substitution reaction, with its iodine or bromine atom as the reaction check point, many nucleophilic reagents, such as alkoxides, amines, etc., can be introduced to obtain corresponding substitution products. This is also a commonly used method in the synthesis of fine chemicals.
When constructing polycyclic aromatic hydrocarbon systems, 1-bromo-2-iodobenzene can also play a role. With suitable cyclization reactions, a fused ring structure can be gradually established. Such polycyclic aromatic hydrocarbons exhibit unique photoelectric properties in the field of organic optoelectronic materials. < Br >
Because there are two different halogen atoms in the molecule, one can be selectively activated according to the difference in reaction conditions, achieving a step-by-step reaction and accurately constructing the structure of the target molecule, providing organic synthesis chemists with flexible and variable strategies to achieve efficient synthesis of complex organic molecules.
What is the preparation method of 1-brom-2-iodobenzene?
1-Bromo-2-iodobenzene is also an organic compound. There are several common methods for its preparation.
One method is to start with o-bromoaniline. First, o-bromoaniline interacts with sodium nitrite and hydrochloric acid at low temperature to obtain diazonium salts. The first step is to maintain a low temperature to prevent the decomposition of diazonium salts. The diazonium salt is obtained, and then mixed with potassium iodide, the diazonium group is replaced by the iodine atom to obtain 1-bromo-2-iodobenzene. During this process, the diazotization reaction needs to be carefully controlled at temperature, and the ratio of reagents used needs to be accurate, otherwise the yield will be affected. < Br >
Another method is to use o-bromobenzoic acid as the starting material. First, the o-bromobenzoic acid is converted into an acyl chloride, which can be obtained by co-heating with sulfoxide chloride. The acyl chloride is formed, and then reacts with iodine and red phosphorus. After a series of complex transformations, the carboxyl group of benzoic acid can be changed to an iodine atom, while the bromine atom is retained, and the final product is 1-bromo-2-iodobenzene. In this way, the preparation of the acyl chloride requires an anhydrous environment, because the acyl chloride is easily hydrolyzed in contact with water, and the subsequent reaction with iodine and red phosphorus also requires suitable reaction conditions, such as temperature and reaction time, which are all related to the purity and yield of the product.
First, benzene is brominated to obtain bromobenzene. Bromobenzene is then nitrified to obtain o-nitrobromobenzene. After the reduction of o-nitrobromobenzene, the nitro group is changed to an amino group to obtain o-aminobromobenzene. This o-aminobromobenzene can also be prepared by the step of diazotization and reaction with potassium iodide. However, this route is long and there are many steps. Each step requires fine operation to avoid side reactions before pure 1-bromo-2-iodobenzene can be obtained.
What is the market price of 1-brom-2-iodobenzene?
The market price of 1-bromo-2-iodobenzene is difficult to determine. Its price often varies for many reasons.
The supply and demand situation is the first. If the market demand for 1-bromo-2-iodobenzene is strong, the supply is limited. If there are few manufacturers, low output, or scarce raw materials cause output to be limited, the price will rise. On the contrary, if the demand is weak and the supply is abundant, the price will easily fall.
Furthermore, the production cost is also the key. To prepare 1-bromo-2-iodobenzene, the price of raw materials bromine and iodine often fluctuates. If the price of raw materials rises, the production cost increases, and the product price will also rise. In addition, the production process is simple and simple, and the amount of energy consumption affects the cost and selling price. Complex processes and high energy consumption will increase costs, which in turn will raise prices.
Market competition also affects its price. There are many manufacturers producing this product in the market, and the competition is fierce. Manufacturers compete for share or reduce prices to promote; if the market is almost monopolized, manufacturers can set prices based on their advantages.
Regional factors cannot be ignored. In different places, due to differences in transportation costs and tax policies, the price of 1-bromo-2-iodobenzene is also different. In remote places, transportation costs are high, and prices are higher; in places with favorable tax policies, costs are reduced, and prices may also be reduced. < Br >
To know the exact market price of 1-bromo-2-iodobenzene, it is advisable to consult chemical product suppliers, distributors, or chemical product trading platforms to obtain real-time and accurate prices.