Names | |
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Preferred IUPAC name Hexabromobenzene | |
Other names
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Identifiers | |
3D model (JSmol) | |
ChemSpider | |
ECHA InfoCard | 100.001.613 |
PubChem CID | |
UNII | |
CompTox Dashboard (EPA) | |
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Properties | |
C6Br6 | |
Molar mass | 551.490 g·mol−1 |
Appearance | Monoclinic needles or white powder. [1] |
Odor | Odorless [2] |
Melting point | 327 °C (621 °F; 600 K) [2] |
0.16x10−3 mg/L (insoluble) [1] | |
Solubility | Slightly soluble in Ethanol, Diethyl ether [3] |
Solubility in Acetic acid | Soluble [3] |
Solubility in Benzene | 10% [4] |
Solubility in Chloroform | 10% [4] |
Solubility in Petroleum ether | 10% [4] |
log P | 6.07 [1] |
Hazards | |
GHS labelling: | |
[2] | |
Danger [2] | |
H302, H312, H315, H319, H332, H335, H413 [1] | |
P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P312, P304+P340, P305+P351+P338, P312, P321, P322, P330, P332+P313, P362, P363, P403+P233, P405, P501 [1] | |
NFPA 704 (fire diamond) | |
Safety data sheet (SDS) | LCSS 6905 |
Related compounds | |
Related compounds | Hexafluorobenzene Hexachlorobenzene Hexaiodobenzene |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
Hexabromobenzene is an aryl bromide and a six-substituted bromobenzene in which all six positions of the central benzene ring are bonded to a bromine atom.
Hexabromobenzene has seen use in high voltage capacitors as a flame retardant. [5] It also has applications as a starting material in the formation of thin graphene-like films for low cost energy storage devices and capacitors. [6]
It can be prepared by reacting Benzene (C6H6) with 6 Bromine (Br2) in the presence of a heat and UV light. This reaction is known as Bromination of Benzene:
This reaction produces Hexabromobenzene (HBB), also known as Perbromobenzene and Benzyl hexabromide, and six Hydrogen Bromide (HBr), or six Hydrogen ions ( H+) and 6 Bromide ions (Br-).
The reaction to form Hexabromobenzene, known as Bromination of Benzene, involves substitution of hydrogens by bromides. Electrophilic aromatic substitution [7] is a general method of derivatizing hexabromobenzene. Benzene is sufficiently nucleophilic that it undergoes substitution by bromide ions to give the substituted derivatives, hexabromobenzene. [8]
Hexabromobenzene is a white powder in physical form. It's not soluble in water but is soluble in ethanol, ether, and benzene. Molecular weigh t is 551.7 g/mol. Melting point of 327 °C. Whiteness percent of 93.0. Its bromine content is above 86%, and it represents high efficacy. Stable. Incompatible with strong oxidizing agents. A balanced pH range is between 4.5 and 7.5. It has excellent integration flexibility with several resins and plastics due to its solubility in substances like ethanol, ether, and benzene. [9]
Hexabromobenzene (HBB) poses significant dangers due to its toxicity profile as classified by the GHS (Globally Harmonized System of Classification and Labeling of Chemicals). Classified as GHS07, HBB exhibits acute toxicity via oral, dermal, and inhalation routes, categorizing it under category 4 for this hazard. Additionally, it induces skin and eye irritation, classified under category 2 for both. Moreover, HBB is known to cause skin sensitization (category 1) and specific target organ toxicity upon single exposure (category 3), with the respiratory system being the primary target organ. [10]
Notably, the acute toxicity of HBB is observed to decrease with an increase in the number of bromine atoms in the molecule. [11] However, the potential for necrotic changes varies based on the position of these bromine atoms within the molecule. There are severe health risks associated with HBB exposure, warranting careful handling and stringent safety measures in its use and management. [10]
Hexabromobenzene (HBB) finds extensive use as a fire retardant additive in a range of materials including plastics, paper, and electrical goods, where it serves as a top-tier flame retardant. With an impressive melting point of 327 °C and a high bromide content of 86%, HBB significantly enhances the fire safety of these materials. [12] Its ability to suppress combustion effectively makes it a sought-after choice in industries concerned with fire prevention. However, its widespread application also leads to its dispersion in the environment. Additionally, HBB can undergo proto bromination reactions when treated with sodium methoxide in methanol and ethyl methyl ketone, yielding a mixture of tribromobenzene.Despite its efficacy in fire retardation, the environmental and health impacts of HBB underscore the importance of careful handling and monitoring in its utilization. [10]
The influences of five organic cosolvents (acetone, methanol, ethanol, THF, or DMSO) on hexabromobenzene (HBB) degradation catalyzed by one typical reactive material montmorillonite-templated sub nanoscale zero-valent iron (CZVI) was investigated.The CZVI-catalyzed HBB degradation mechanism was proposed as the electron transfer between zero-valent iron and HBB, which led to formation of four debromination products. [11]
hexabromobenzene also serves as one of the key polyhalogenated aromatic compounds used in the bottom-up synthesis process of graphene-like films. Through electrochemical reduction, HBB contributes to the formation of polyaromatic ring structures alongside other compounds like hexafluorobenzene (HFB) and hexachlorobenzene (HCB). It facilitates the creation of graphene-like carbon films upon thermal annealing, offering a cost-effective approach without the need for sophisticated equipment. [6]
Hexabromobenzene (HBB) was utilized in a study investigating its metabolic fate in female rats, wherein the substance was orally administered at doses of 16.6 mg/kg body weight every other day for a span of 2 weeks. Analysis of the rats' excreta revealed the presence of various metabolites, including unchanged HBB, penta bromobenzene, as well as oxygen- and sulfur-containing compounds. [13]
Bromine is a chemical element; it has symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig and Antoine Jérôme Balard, its name was derived from the Ancient Greek βρῶμος (bromos) meaning "stench", referring to its sharp and pungent smell.
The halogens are a group in the periodic table consisting of six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and the radioactive elements astatine (At) and tennessine (Ts), though some authors would exclude tennessine as its chemistry is unknown and is theoretically expected to be more like that of gallium. In the modern IUPAC nomenclature, this group is known as group 17.
Toluene, also known as toluol, is a substituted aromatic hydrocarbon with the chemical formula C6H5CH3, often abbreviated as PhCH3, where Ph stands for phenyl group. It is a colorless, water-insoluble liquid with the odor associated with paint thinners. It is a mono-substituted benzene derivative, consisting of a methyl group (CH3) attached to a phenyl group by a single bond. As such, its systematic IUPAC name is methylbenzene. Toluene is predominantly used as an industrial feedstock and a solvent.
In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula C6H5, and is often represented by the symbol Ph. The phenyl group is closely related to benzene and can be viewed as a benzene ring, minus a hydrogen, which may be replaced by some other element or compound to serve as a functional group. A phenyl group has six carbon atoms bonded together in a hexagonal planar ring, five of which are bonded to individual hydrogen atoms, with the remaining carbon bonded to a substituent. Phenyl groups are commonplace in organic chemistry. Although often depicted with alternating double and single bonds, the phenyl group is chemically aromatic and has equal bond lengths between carbon atoms in the ring.
1,2-Dibromoethane, also known as ethylene dibromide (EDB), is an organobromine compound with the chemical formula C
2H
4Br
2. Although trace amounts occur naturally in the ocean, where it is probably formed by algae and kelp, it is mainly synthetic. It is a dense colorless liquid with a faint, sweet odor, detectable at 10 ppm, and is a widely used and sometimes-controversial fumigant. The combustion of 1,2-dibromoethane produces hydrogen bromide gas that is significantly corrosive.
In chemistry, halogenation is a chemical reaction that entails the introduction of one or more halogens into a compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. This kind of conversion is in fact so common that a comprehensive overview is challenging. This article mainly deals with halogenation using elemental halogens. Halides are also commonly introduced using salts of the halides and halogen acids. Many specialized reagents exist for and introducing halogens into diverse substrates, e.g. thionyl chloride.
In organic chemistry, an aryl halide is an aromatic compound in which one or more hydrogen atoms, directly bonded to an aromatic ring are replaced by a halide. The haloarene are different from haloalkanes because they exhibit many differences in methods of preparation and properties. The most important members are the aryl chlorides, but the class of compounds is so broad that there are many derivatives and applications.
Bromobenzene is an aryl bromide and the simplest of the bromobenzenes, consisting of a benzene ring substituted with one bromine atom. Its chemical formula is C6H5Br. It is a colourless liquid although older samples can appear yellow. It is a reagent in organic synthesis.
Sodium bromide is an inorganic compound with the formula NaBr. It is a high-melting white, crystalline solid that resembles sodium chloride. It is a widely used source of the bromide ion and has many applications.
Biphenyl is an organic compound that forms colorless crystals. Particularly in older literature, compounds containing the functional group consisting of biphenyl less one hydrogen may use the prefixes xenyl or diphenylyl.
The tropylium ion or cycloheptatrienyl cation is an aromatic species with a formula of [C7H7]+. Its name derives from the molecule tropine from which cycloheptatriene (tropylidene) was first synthesized in 1881. Salts of the tropylium cation can be stable, even with nucleophiles of moderate strength e.g., tropylium tetrafluoroborate and tropylium bromide (see below). Its bromide and chloride salts can be made from cycloheptatriene and bromine or phosphorus pentachloride, respectively.
Zinc bromide (ZnBr2) is an inorganic compound with the chemical formula ZnBr2. It is a colourless salt that shares many properties with zinc chloride (ZnCl2), namely a high solubility in water forming acidic solutions, and good solubility in organic solvents. It is hygroscopic and forms a dihydrate ZnBr2·2H2O.
Arsenic tribromide is an inorganic compound with the formula AsBr3, it is a bromide of arsenic. Arsenic is a chemical element that has the symbol As and atomic number 33. This pyramidal molecule is the only known binary arsenic bromide. AsBr3 is noteworthy for its very high refractive index of approximately 2.3. It also has a very high diamagnetic susceptibility. The compound exists as colourless deliquescent crystals that fume in moist air.
Bromobenzenes are a group of aryl bromides/halobenzenes consisting of one or more bromine atoms as substituents on a benzene core. They have the formula C6H6–nBrn, where n = 1–6 is the number of bromine atoms. Depending on the number of bromine substituents, there may be several constitutional isomers possible.
Hexachlorocyclohexane (HCH), C
6H
6Cl
6, is any of several polyhalogenated organic compounds consisting of a six-carbon ring with one chlorine and one hydrogen attached to each carbon. This structure has nine stereoisomers, which differ by the stereochemistry of the individual chlorine substituents on the cyclohexane. It is sometimes erroneously called "benzene hexachloride" (BHC). They have been used as models for analyzing the effects of different geometric positions of the large atoms with dipolar bonds on the stability of the cyclohexane conformation. The isomers are poisonous, pesticidal, and persistent organic pollutants, to varying degrees.
Organobromine chemistry is the study of the synthesis and properties of organobromine compounds, also called organobromides, which are organic compounds that contain carbon bonded to bromine. The most pervasive is the naturally produced bromomethane.
Phenylsodium C6H5Na is an organosodium compound. Solid phenylsodium was first isolated by Nef in 1903. Although the behavior of phenylsodium and phenyl magnesium bromide are similar, the organosodium compound is very rarely used.
4-Fluorobromobenzene is a mixed aryl halide (aryl fluoride and aryl bromide) with the formula C6H4BrF. It is a derivative of benzene, with a bromine atom bonded para to a fluorine atom. It has uses as a precursor to some pharmaceuticals, as an agrochemical intermediate, and in organic synthesis. It is a colorless liquid of low acute toxicity.
1,2,4,5-Tetrabromobenzene is an aryl bromide and a four-substituted bromobenzene with the formula C6H2Br4. It is one of three isomers of tetrabromobenzene. The compound is a white solid. 1,2,4,5-Tetrabromobenzene is an important metabolite of the flame retardant hexabromobenzene.
A bromophenol is an organic compound consisting of hydroxyl groups and bromine atoms bonded to a benzene ring. They may be viewed as hydroxyl derivatives of bromobenzene, or as brominated derivatives of phenol. There are five basic types of bromophenols and 19 different bromophenols in total when positional isomerism is taken into account. Bromophenols are produced by electrophilic halogenation of phenol with bromine.