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Tetraiodobenzene
Tetraiodobenzenes form a group of iodobenzenes with four iodine atoms as substituents (C6H2I4). By their different arrangement, three constitutional isomers are possible. See also *Tetrachlorobenzene Tetrachlorobenzene is any of three isomeric chlorobenzenes with the molecular formula . They differ by the positions of the chlorine atoms around the ring. Tetrachlorobenzenes are colorless crystalline compounds. Properties Synthesis 1,2,4,5-T ... * Tetrabromobenzene References ''Handbook of Data on Common Organic Compounds'', S. 466 (). {{cite journal , doi=10.1021/jo00172a063 , title=Periodination of benzene with periodate/Iodide , date=1983 , last1=Mattern , first1=Daniell Lewis , journal=The Journal of Organic Chemistry , volume=48 , issue=24 , pages=4772ā4773 Iodobenzenes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodobenzenes
Iodobenzenes are a group of aryl iodides/halobenzenes consisting of one or more iodine atoms as substituents on a benzene core. They have the formula C6H6ā''n''I''n'', where ''n'' = 1ā6 is the number of iodine atoms. Depending on the number of iodine substituents, there may be several constitutional isomers possible. * Monoiodobenzene * Diiodobenzene ** 1,2-Diiodobenzene ** 1,3-Diiodobenzene ** * ** 1,2,3-Triiodobenzene ** 1,2,4-Triiodobenzene ** 1,3,5-Triiodobenzene * Tetraiodobenzene ** 1,2,3,4-Tetraiodobenzene ** 1,2,3,5-Tetraiodobenzene ** 1,2,4,5-Tetraiodobenzene * Pentaiodobenzene * Hexaiodobenzene See also *Fluorobenzenes *Chlorobenzenes *Bromobenzenes Iodobenzenes, {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrachlorobenzene
Tetrachlorobenzene is any of three isomeric chlorobenzenes with the molecular formula . They differ by the positions of the chlorine atoms around the ring. Tetrachlorobenzenes are colorless crystalline compounds. Properties Synthesis 1,2,4,5-Tetrachlorobenzene can be produced by electrophilic halogenation of benzenes and some chlorobenzenes. 1,2,3,4-Tetrachlorobenzene can only be produced by chlorination of 1,3,5-trichlorobenzene. Uses 1,2,4,5-Tetrachlorobenzene once was used as intermediates in the production of pesticides, specifically 2,4,5-trichlorophenol and 2,4,5-trichlorophenoxyacetic acid. This method has been discontinued because it also produced 2,3,7,8-tetrachlorodibenzo-p-dioxin 2,3,7,8-Tetrachlorodibenzo-''p-''dioxin (TCDD) is a polychlorinated dibenzo''-p-''dioxin (sometimes shortened, though inaccurately, to simply ''dioxin'') with the chemical formula CHClO. Pure TCDD is a colorless solid with no distinguishable .... See also * Tetrabromobenzene * Te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iodine
Iodine is a chemical element; it has symbol I and atomic number 53. The heaviest of the stable halogens, it exists at standard conditions as a semi-lustrous, non-metallic solid that melts to form a deep violet liquid at , and boils to a violet gas at . The element was discovered by the French chemist Bernard Courtois in 1811 and was named two years later by Joseph Louis Gay-Lussac, after the Ancient Greek , meaning 'violet'. Iodine occurs in many oxidation states, including iodide (Iā), iodate (), and the various periodate anions. As the heaviest essential mineral nutrient, iodine is required for the synthesis of thyroid hormones. Iodine deficiency affects about two billion people and is the leading preventable cause of intellectual disabilities. The dominant producers of iodine today are Chile and Japan. Due to its high atomic number and ease of attachment to organic compounds, it has also found favour as a non-toxic radiocontrast material. Because of the spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Substituent
In organic chemistry, a substituent is one or a group of atoms that replaces (one or more) atoms, thereby becoming a moiety in the resultant (new) molecule. The suffix ''-yl'' is used when naming organic compounds that contain a single bond replacing one hydrogen; ''-ylidene'' and ''-ylidyne'' are used with double bonds and triple bonds, respectively. In addition, when naming hydrocarbons that contain a substituent, positional numbers are used to indicate which carbon atom the substituent attaches to when such information is needed to distinguish between isomers. Substituents can be a combination of the inductive effect and the mesomeric effect. Such effects are also described as electron-rich and electron withdrawing. Additional steric effects result from the volume occupied by a substituent. The phrases ''most-substituted'' and ''least-substituted'' are frequently used to describe or compare molecules that are products of a chemical reaction. In this terminology, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constitutional Isomers
In chemistry, a structural isomer (or constitutional isomer in the IUPAC nomenclature) of a compound is a compound that contains the same number and type of atoms, but with a different connectivity (i.e. arrangement of bonds) between them. The term metamer was formerly used for the same concept. For example, butanol , methyl propyl ether , and diethyl ether have the same molecular formula but are three distinct structural isomers. The concept applies also to polyatomic ions with the same total charge. A classical example is the cyanate ion and the fulminate ion . It is also extended to ionic compounds, so that (for example) ammonium cyanate and urea are considered structural isomers,William F. Bynum, E. Janet Browne, Roy Porter (2014)''Dictionary of the History of Science'' page 218. and so are methylammonium formate and ammonium acetate . Structural isomerism is the most radical type of isomerism. It is opposed to stereoisomerism, in which the atoms and bonding sch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2,3,4-Tetraiodobenzene
Onekama ( ) is a village in Manistee County in the U.S. state of Michigan. The population was 399 at the 2020 census. The village is located on the northeast shore of Portage Lake and is surrounded by Onekama Township. The town's name is derived from ''Ona-ga-maa'', an Anishinaabe word which means "singing water". History The predecessor of the village of Onekama was the settlement of Portage at Portage Point, first established in 1845, at the western end of Portage Lake, at the outlet of Portage Creek. In 1871, when landowners around the land-locked lake became exasperated with the practices of the Portage Sawmill, they took the solution into their own hands and dug a channel through the narrow isthmus, opening a waterway that lowered the lake by and brought it to the same level as Lake Michigan. When this action dried out Portage Creek on May 14, 1871, the settlement, which had only the week before been designated as "Onekama" with a post office under that name, moved to th ... [...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] |
PubChem
PubChem is a database of Chemistry, chemical molecules and their activities against biological assays. The system is maintained by the National Center for Biotechnology Information (NCBI), a component of the National Library of Medicine, which is part of the United States National Institutes of Health (NIH). PubChem can be accessed for free through a web user interface. Millions of compound structures and descriptive datasets can be freely downloaded via FTP. PubChem contains multiple substance descriptions and small molecules with fewer than 100 atoms and 1,000 bonds. More than 80 database vendors contribute to the growing PubChem database. History PubChem was released in 2004 as a component of the Molecular Libraries Program (MLP) of the NIH. As of November 2015, PubChem contains more than 150 million depositor-provided substance descriptions, 60 million unique chemical structures, and 225 million biological activity test results (from over 1 million assay experiments performe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sum Formula
In chemistry, the empirical formula of a chemical compound is the simplest whole number ratio of atoms present in a compound. A simple example of this concept is that the empirical formula of sulfur monoxide, or SO, is simply SO, as is the empirical formula of disulfur dioxide, S2O2. Thus, sulfur monoxide and disulfur dioxide, both compounds of sulfur and oxygen, have the same empirical formula. However, their molecular formulas, which express the number of atoms in each molecule of a chemical compound, are not the same. An empirical formula makes no mention of the arrangement or number of atoms. It is standard for many ionic compounds, like calcium chloride (CaCl2), and for macromolecules, such as silicon dioxide (SiO2). The molecular formula, on the other hand, shows the number of each type of atom in a molecule. The structural formula shows the arrangement of the molecule. It is also possible for different types of compounds to have equal empirical formulas. In the early days ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
