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Trimethylbenzenes
The trimethylbenzenes constitute a group of substances of aromatic hydrocarbons, which structure consists of a benzene ring with three methyl groups (–CH3) as a substituent. Through their different arrangement, they form three structural isomers with the molecular formula C9H12. They also belong to the group of C3-Benzenes, C3-benzenes. The best-known isomer is mesitylene. : References {{Authority control Alkylbenzenes C3-Benzenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkylbenzenes
An alkylbenzene is a chemical compound that contains a monocyclic aromatic ring attaching to one or more saturated hydrocarbon chains. Alkylbenzenes are derivatives of benzene, in which one or more hydrogen atoms are replaced by Alkyl group, alkyl groups. The simplest member, toluene (or methylbenzene), has the hydrogen atom of the benzene ring replaced by a methyl group. The chemical formula of alkylbenzenes is CnH2n-6. Alkylbenzenes are a very important class of Hydrocarbon, hydrocarbons, especially in the synthetic production industry. It is the raw material in the production of synthetic Alkylbenzene sulfonates, sulfonate detergents, which are found in a variety of household products such as soap, shampoo, toothpaste, laundry detergent, etc. Linear alkylbenzene, Linear alkylbenzenes (LAB) and branched alkylbenzenes (BAB) are families of alkylbenzene used to prepare Alkylbenzene sulfonates, synthetic sulfonates. However, LABs are more industrially favoured since the discovery o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C3-Benzenes
The C3-benzenes are a class of organic aromatic compounds which contain a benzene ring and three other carbon atoms. For the hydrocarbons with no further unsaturation, there are four isomers. The chemical formula for all the saturated isomers is C9H12. There are three trimethylbenzenes, three ethylmetylbenzenes, and two propylbenzene isomers. 1980s American gasoline contained about 3-4% C3-benzenes. Image:1,2,3-trimethylbenzene 200.svg, 1,2,3-trimethylbenzene or Hemellitene Image:1,2,4-Trimethylbenzene.svg, 1,2,4-Trimethylbenzene or Pseudocumene Image:Mesitylen.svg, 1,3,5-Trimethylbenzene or Mesitylene Image:1,2-Ethylmethylbenzol Structural Formulae V.2.svg, 1,2-Ethylmethylbenzene Image:1,3-Ethylmethylbenzol Structural Formulae V.2.svg, 1,3-Ethylmethylbenzene Image:1,4-Ethylmethylbenzol Structural Formulae V.2.svg, 1,4-Ethylmethylbenzene Image:Cumol.svg, Cumene Image:Isocumene.svg, N-Propylbenzene, ''n''-Propylbenzene Image:Trans-Propenylbenzene.svg, trans-Propenylbenzene, ''trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic Hydrocarbons
Aromatic compounds or arenes are organic compounds "with a chemistry typified by benzene" and "cyclically conjugated." The word "aromatic" originates from the past grouping of molecules based on odor, before their general chemical properties were understood. The current definition of aromatic compounds does not have any relation to their odor. Aromatic compounds are now defined as cyclic compounds satisfying Hückel's rule. Aromatic compounds have the following general properties: * Typically unreactive * Often non polar and hydrophobic * High carbon-hydrogen ratio * Burn with a strong sooty yellow flame, due to high C:H ratio * Undergo electrophilic substitution reactions and nucleophilic aromatic substitutions Arenes are typically split into two categories - benzoids, that contain a benzene derivative and follow the benzene ring model, and non-benzoids that contain other aromatic cyclic derivatives. Aromatic compounds are commonly used in organic synthesis and are involved in m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzene Ring
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar hexagonal ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline. It is used primarily as a precursor to the manufacture of chemicals with more complex structures, such as ethylbenzene and cumene, of which billions of kilograms are produced annually. Although benzene is a major industrial chemical, it finds limited use in consumer items because of its toxicity. Benzene is a volatile organic compound. Benzene is classified as a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Group
In organic chemistry, a methyl group is an alkyl derived from methane, containing one carbon atom bonded to three hydrogen atoms, having chemical formula (whereas normal methane has the formula ). In formulas, the group is often abbreviated as Me. This hydrocarbon group occurs in many organic compounds. It is a very stable group in most molecules. While the methyl group is usually part of a larger molecule, bonded to the rest of the molecule by a single covalent bond (), it can be found on its own in any of three forms: methanide anion (), methylium cation () or methyl radical (). The anion has eight valence electrons, the radical seven and the cation six. All three forms are highly reactive and rarely observed. Methyl cation, anion, and radical Methyl cation The methylium cation () exists in the gas phase, but is otherwise not encountered. Some compounds are considered to be sources of the cation, and this simplification is used pervasively in organic chemistry. For ex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The National Center For Biotechnology Information
The National Center for Biotechnology Information (NCBI) is part of the National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. The NCBI is located in Bethesda, Maryland, and was founded in 1988 through legislation sponsored by US Congressman Claude Pepper. The NCBI houses a series of databases relevant to biotechnology and biomedicine and is an important resource for bioinformatics tools and services. Major databases include GenBank for DNA sequences and PubMed, a bibliographic database for biomedical literature. Other databases include the NCBI Epigenomics database. All these databases are available online through the Entrez search engine. NCBI was directed by David Lipman, one of the original authors of the BLAST sequence alignment program and a widely respected figure in bioinformatics. GenBank NCBI had responsibility for making available the GenBank DNA sequence database ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Scottish Environment Protection Agency
The Scottish Environment Protection Agency (SEPA; ) is Scotland's Environmental regulation, environmental regulator and national flood forecasting, flood warning and strategic flood risk management authority.Environment Act (1995). (c.2), London, HMSO [Accessed 29 April 2010]. Its main role is to protect and improve Scotland's environment. SEPA does this by helping business and industry to understand their environmental responsibilities, enabling customers to comply with legislation and good practice and to realise the economic benefits of good environmental practice. One of the ways SEPA does this is through the NetRegs environmental guidance service. It protects communities by regulating activities that can cause harmful pollution and by monitoring the quality of Scotland's air ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesitylene
Mesitylene or 1,3,5-trimethylbenzene is a derivative of benzene with three methyl substituents positioned symmetrically around the ring. The other two isomeric trimethylbenzenes are 1,2,4-trimethylbenzene (pseudocumene) and 1,2,3-trimethylbenzene (hemimellitene). All three compounds have the formula C6H3(CH3)3, which is commonly abbreviated C6H3Me3. Mesitylene is a colorless liquid with sweet aromatic odor. It is a component of coal tar, which is its traditional source. It is a precursor to diverse fine chemicals. The mesityl group (Mes) is a substituent with the formula C6H2Me3 and is found in various other compounds. Preparation Mesitylene is prepared by transalkylation of xylene over solid acid catalyst:Karl Griesbaum, Arno Behr, Dieter Biedenkapp, Heinz-Werner Voges, Dorothea Garbe, Christian Paetz, Gerd Collin, Dieter Mayer, Hartmut Höke “Hydrocarbons” in Ullmann's Encyclopedia of Industrial Chemistry 2002 Wiley-VCH, Weinheim. . :2 C6H4(CH3)2 ⇌ C6H ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemellitene
1,2,3-Trimethylbenzene is an organic compound with the chemical formula CH(CH). Classified as an aromatic hydrocarbon, it is a flammable colorless liquid. It is nearly insoluble in water but soluble in organic solvents. The compound occurs naturally in coal tar and petroleum. It is one of the three isomers of trimethylbenzene. It is used in jet fuel, mixed with other hydrocarbons, to prevent the formation of solid particles which might damage the engine. German chemist first prepared the hydrocarbon in 1882 and designated it hemellitol as a reference to the trivial name of hexamethylbenzene. Four years later he also discovered it in the coal tar. Production Industrially, it is isolated from the C aromatic hydrocarbon fraction during petroleum distillation. It is also generated by methylation of toluene and xylene In organic chemistry, xylene or xylol (; IUPAC name: dimethylbenzene) are any of three organic compounds with the formula . They are derived from the subst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Structural Formula
The structural formula of a chemical compound is a graphic representation of the molecular structure (determined by structural chemistry methods), showing how the atoms are connected to one another. The chemical bonding within the molecule is also shown, either explicitly or implicitly. Unlike other chemical formula types, which have a limited number of symbols and are capable of only limited descriptive power, structural formulas provide a more complete geometric representation of the molecular structure. For example, many chemical compounds exist in different isomeric forms, which have different enantiomeric structures but the same molecular formula. There are multiple types of ways to draw these structural formulas such as: Lewis structures, condensed formulas, skeletal formulas, Newman projections, Cyclohexane conformations, Haworth projections, and Fischer projections. Several systematic chemical naming formats, as in chemical databases, are used that are equivalent to, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemimellitene
1,2,3-Trimethylbenzene is an organic compound with the chemical formula CH(CH). Classified as an aromatic hydrocarbon, it is a flammable colorless liquid. It is nearly insoluble in water but soluble in organic solvents. The compound occurs naturally in coal tar and petroleum. It is one of the three isomers of trimethylbenzene. It is used in jet fuel, mixed with other hydrocarbons, to prevent the formation of solid particles which might damage the engine. German chemist first prepared the hydrocarbon in 1882 and designated it hemellitol as a reference to the trivial name of hexamethylbenzene. Four years later he also discovered it in the coal tar. Production Industrially, it is isolated from the C aromatic hydrocarbon fraction during petroleum distillation. It is also generated by methylation of toluene and xylene In organic chemistry, xylene or xylol (; IUPAC name: dimethylbenzene) are any of three organic compounds with the formula . They are derived from the subst ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
