|
Sulfonyl Diazide
Sulfuryl diazide or sulfuryl azide is a chemical compound with the molecular formula . It was first described in the 1920s when its reactions with benzene and ''p''-xylene were studied by Theodor Curtius and Karl Friedrich Schmidt. The compound is reported as having "exceedingly explosive, unpredictable properties" and "in many cases very violent explosions occurred without any apparent reason". It was not until 2011 that sulfuryl diazide was isolated in a pure enough state to be fully characterized. It was characterized by infrared and Raman spectroscopy; its structure in the solid state was determined by x-ray crystallography. Its melting point is -15 °C. It was prepared by the reaction of sulfuryl chloride () with sodium azide () using acetonitrile as solvent: : Sulfuryl diazide has been used as a reagent to perform reactions that remove nitrogen from heterocyclic compounds: : See also * Trifluoromethanesulfonyl azide Trifluoromethanesulfonyl azide or triflyl azide ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzene
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar 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 structure, 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. History Discovery The word "''benzene''" derives from "''gum benzoin''" ( ben ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetonitrile
Acetonitrile, often abbreviated MeCN (methyl cyanide), is the chemical compound with the formula and structure . This colourless liquid is the simplest organic nitrile ( hydrogen cyanide is a simpler nitrile, but the cyanide anion is not classed as organic). It is produced mainly as a byproduct of acrylonitrile manufacture. It is used as a polar aprotic solvent in organic synthesis and in the purification of butadiene. The skeleton is linear with a short distance of 1.16 Å. Acetonitrile was first prepared in 1847 by the French chemist Jean-Baptiste Dumas. Applications Acetonitrile is used mainly as a solvent in the purification of butadiene in refineries. Specifically, acetonitrile is fed into the top of a distillation column filled with hydrocarbons including butadiene, and as the acetonitrile falls down through the column, it absorbs the butadiene which is then sent from the bottom of the tower to a second separating tower. Heat is then employed in the separatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azido Compounds
In chemistry, azide is a linear, polyatomic anion with the formula and structure . It is the conjugate base of hydrazoic acid . Organic azides are organic compounds with the formula , containing the azide functional group. The dominant application of azides is as a propellant in air bags. Preparation Sodium azide is made industrially by the reaction of nitrous oxide, with sodium amide in liquid ammonia as solvent: : Many inorganic azides can be prepared directly or indirectly from sodium azide. For example, lead azide, used in detonators, may be prepared from the metathesis reaction between lead nitrate and sodium azide. An alternative route is direct reaction of the metal with silver azide dissolved in liquid ammonia. Some azides are produced by treating the carbonate salts with hydrazoic acid. Bonding Azide is isoelectronic with carbon dioxide , cyanate , nitrous oxide , nitronium ion and cyanogen fluoride NCF. Per valence bond theory, azide can be desc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trifluoromethanesulfonyl Azide
Trifluoromethanesulfonyl azide or triflyl azide is an organic azide used as a reagent in organic synthesis. Preparation Trifluoromethanesulfonyl azide is not commercially available. It is prepared before use by reacting trifluoromethanesulfonic anhydride with sodium azide, traditionally in dichloromethane. However, use of dichloromethane should be avoided because sodium azide is known to generate highly explosive azido-chloromethane and diazidomethane in situ by nucleophilic substitution on dichloromethane.Cavender, C. J.; Shiner, V. J., Jr. J. Org. Chem. (1972), 37, 3567. Moreover, the volatility of dichloromethane is a liability, as unsolvated triflyl azide is a detonation hazard. The reaction may also be carried out in toluene, acetonitrile, or pyridine. : (Tf = ) The trifluoromethanesulfonic anhydride starting material is rather expensive, and the product is explosive, and does not store well. As a result, imidazole-1-sulfonyl azide has been developed as an alternative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science Translational Medicine
''Science Translational Medicine'' is an interdisciplinary medical journal established in October 2009 by the American Association for the Advancement of Science. It covers basic, translational, and clinical research on human diseases. According to '' Web of Science'', the journal has a 2021 impact factor of 19.319 science.org Abstracting and indexing The journal is abstracted and indexed by the major services with a focus on and , including |
Derek Lowe (chemist)
Derek Lowe is a medicinal chemist working on preclinical drug discovery in the pharmaceutical industry. Lowe has published a blog about this field, "In the Pipeline", since 2002 and is a columnist for the Royal Society of Chemistry's '' Chemistry World''. Biography Lowe (born in Harrisburg, Arkansas) got his BA from Hendrix College and his PhD in organic chemistry from Duke University on synthesis of natural products, before spending time in Germany on a Humboldt Fellowship. Lowe was the one of the first people to blog from inside the pharmaceutical industry, with the approval of his supervisor and the company legal department, and one of the first science bloggers. By 2006, his blog had between 3,000 and 4,000 visitors per day during the workweek; he covered business matters, trends and issues in medicinal chemistry, and legal matters like patent law and regulation. At that time he was working at a pharmaceutical company doing hit to lead medical chemistry work. his blog re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocyclic Compound
A heterocyclic compound or ring structure is a cyclic compound that has atoms of at least two different elements as members of its ring(s). Heterocyclic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of these heterocycles. Examples of heterocyclic compounds include all of the nucleic acids, the majority of drugs, most biomass (cellulose and related materials), and many natural and synthetic dyes. More than half of known compounds are heterocycles. 59% of US FDA-approved drugs contain nitrogen heterocycles. Classification The study of heterocyclic chemistry focuses especially on unsaturated derivatives, and the preponderance of work and applications involves unstrained 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of pyridine, thiophene, pyrrole, and furan are quin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reagent
In chemistry, a reagent ( ) or analytical reagent is a substance or compound added to a system to cause a chemical reaction, or test if one occurs. The terms ''reactant'' and ''reagent'' are often used interchangeably, but reactant specifies a substance ''consumed'' in the course of a chemical reaction. ''Solvents'', though involved in the reaction mechanism, are usually not called reactants. Similarly, '' catalysts'' are not consumed by the reaction, so they are not reactants. In biochemistry, especially in connection with enzyme-catalyzed reactions, the reactants are commonly called substrates. Definitions Organic chemistry In organic chemistry, the term "reagent" denotes a chemical ingredient (a compound or mixture, typically of inorganic or small organic molecules) introduced to cause the desired transformation of an organic substance. Examples include the Collins reagent, Fenton's reagent, and Grignard reagents. Analytical chemistry In analytical chemistry, a reag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P-Xylene
''p''-Xylene ( ''para''-xylene) is an aromatic hydrocarbon. It is one of the three isomers of dimethylbenzene known collectively as xylenes. The ''p-'' stands for ''para-'', indicating that the two methyl groups in ''p''-xylene occupy the diametrically opposite substituent positions 1 and 4. It is in the positions of the two methyl groups, their arene substitution pattern, that it differs from the other isomers, ''o''-xylene and ''m''-xylene. All have the same chemical formula C6H4(CH3)2. All xylene isomers are colorless and highly flammable. The odor threshold of ''p''-xylene is 0.62 parts per million (ppm). Production The production of ''p''-xylene is industrially significant, with annual demand estimated at 37 million tons in 2014, and still on the increase. ''p''-Xylene is produced by catalytic reforming of petroleum naphtha as part of the BTX aromatics (benzene, toluene and the xylene isomers) extracted from the catalytic reformate. The ''p''-xylene is then separated out ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfuryl Chloride
Sulfuryl chloride is an inorganic compound with the formula SO2Cl2. At room temperature, it is a colorless liquid with a pungent odor. Sulfuryl chloride is not found in nature, as can be inferred from its rapid hydrolysis. Sulfuryl chloride is commonly confused with thionyl chloride, SOCl2. The properties of these two sulfur oxychlorides are quite different: sulfuryl chloride is a source of chlorine whereas thionyl chloride is a source of chloride ions. An alternative IUPAC name is sulfuroyl dichloride. Structure Sulfur is tetrahedral in SO2Cl2 and the oxidation state of the sulfur atom is +6, as in sulfuric acid. Synthesis SO2Cl2 is prepared by the reaction of sulfur dioxide and chlorine in the presence of a catalyst, such as activated carbon. :SO2 + Cl2 → SO2Cl2 The product can be purified by fractional distillation. Legacy routes Sulfuryl chloride was first prepared in 1838 by the French chemist Henri Victor Regnault. Legacy routes include oxidation of thionyl chl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to diffract into many specific directions. By measuring the angles and intensities of these diffracted beams, a crystallographer can produce a three-dimensional picture of the density of electrons within the crystal. From this electron density, the mean positions of the atoms in the crystal can be determined, as well as their chemical bonds, their crystallographic disorder, and various other information. Since many materials can form crystals—such as salts, metals, minerals, semiconductors, as well as various inorganic, organic, and biological molecules—X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences among variou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2.png "Click for more on -> Benzene")
