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Methylthiomethyl Ether
In organic chemistry a methylthiomethyl (MTM) ether is a protective group for hydroxyl groups. Hydroxyl groups are present in many chemical compounds and they must be protected during oxidation, acylation, halogenation, dehydration and other reactions to which they are susceptible. Many kinds of protective groups for hydroxyl groups have been developed and used in organic chemistry, but the number of protective groups for tertiary hydroxyl groups, which are susceptible to acid-catalyzed dehydration, is still small because of their poor reactiveness. They can be easily protected with MTM ethers and recovered in good yield. To introduce an MTM ether to a hydroxyl group, two methods are mainly used. One is a typical Williamson ether synthesis using an MTM halide as an MTM resource and sodium hydride (NaH) as a base. The other is a special method, in which dimethyl sulfoxide (DMSO) and acetic anhydride (Ac2O) are used. In this case, the reaction proceeds with Pummerer rearrangement: M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, and reactions of organic compounds and organic materials, i.e., matter in its various forms that contain carbon atoms.Clayden, J.; Greeves, N. and Warren, S. (2012) ''Organic Chemistry''. Oxford University Press. pp. 1–15. . Study of structure determines their structural formula. Study of properties includes physical and chemical properties, and evaluation of chemical reactivity to understand their behavior. The study of organic reactions includes the chemical synthesis of natural products, drugs, and polymers, and study of individual organic molecules in the laboratory and via theoretical ( in silico) study. The range of chemicals studied in organic chemistry includes hydrocarbons (compounds containing only carbon and hydrogen) as well as compounds based on carbon, but also containing other elements, especially oxygen, nitrogen, sulfur, phosphorus (included in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protecting Group
A protecting group or protective group is introduced into a molecule by chemical modification of a functional group to obtain chemoselectivity in a subsequent chemical reaction. It plays an important role in multistep organic synthesis. In many preparations of delicate organic compounds, some specific parts of their molecules cannot survive the required reagents or chemical environments. Then, these parts, or groups, must be protected. For example, lithium aluminium hydride is a highly reactive but useful reagent capable of reducing esters to alcohols. It will always react with carbonyl groups, and this cannot be discouraged by any means. When a reduction of an ester is required in the presence of a carbonyl, the attack of the hydride on the carbonyl has to be prevented. For example, the carbonyl is converted into an acetal, which does not react with hydrides. The acetal is then called a protecting group for the carbonyl. After the step involving the hydride is complete, the acet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It is commonly used as a solvent in laboratories and as a starting fluid for some engines. It was formerly used as a general anesthetic, until non-flammable drugs were developed, such as halothane. It has been used as a recreational drug to cause intoxication. Production Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if the need arises. Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%. Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Ethanol is mixed with a stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnesium Iodide
Magnesium iodide is the name for the chemical compounds with the formulas MgI2 and its various hydrates MgI2(H2O)x. These salts are typical ionic halides, being highly soluble in water. Uses Magnesium iodide has few commercial uses, but can be used to prepare compounds for organic synthesis. Preparation Magnesium iodide can be prepared from magnesium oxide, magnesium hydroxide, and magnesium carbonate by treatment with hydroiodic acid: :MgO + 2 HI → MgI2 + H2O : Mg(OH)2 + 2 HI → MgI2 + 2 H2O : MgCO3 + 2 HI → MgI2 + CO2 + H2O Reactions Magnesium iodide is stable at high heat under a hydrogen atmosphere, but decomposes in air at normal temperatures, turning brown from the release of elemental iodine. When heated in air, it decomposes completely to magnesium oxide. Another method to prepare MgI2 is mixing powdered elemental iodine and magnesium metal. In order to obtain anhydrous MgI2, the reaction should be conducted in a strictly anhydrous atmosphere; dry-die ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Bicarbonate
Sodium bicarbonate (IUPAC name: sodium hydrogencarbonate), commonly known as baking soda or bicarbonate of soda, is a chemical compound with the formula NaHCO3. It is a salt composed of a sodium cation ( Na+) and a bicarbonate anion ( HCO3−). Sodium bicarbonate is a white solid that is crystalline, but often appears as a fine powder. It has a slightly salty, alkaline taste resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the mineral natron and is found dissolved in many mineral springs. Nomenclature Because it has long been known and widely used, the salt has many different names such as baking soda, bread soda, cooking soda, and bicarbonate of soda and can often be found near baking powder in stores. The term ''baking soda'' is more common in the United States, while ''bicarbonate of soda'' is more common in Australia, United Kingdom and Ireland. and in many northern/central European countries it is called ''Na ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Iodide
Iodomethane, also called methyl iodide, and commonly abbreviated "MeI", is the chemical compound with the formula CH3I. It is a dense, colorless, volatile liquid. In terms of chemical structure, it is related to methane by replacement of one hydrogen atom by an atom of iodine. It is naturally emitted by rice plantations in small amounts. It is also produced in vast quantities estimated to be greater than 214,000 tons annually by algae and kelp in the world's temperate oceans, and in lesser amounts on land by terrestrial fungi and bacteria. It is used in organic synthesis as a source of methyl groups. Preparation and handling Iodomethane is formed via the exothermic reaction that occurs when iodine is added to a mixture of methanol with red phosphorus. The iodinating reagent is phosphorus triiodide that is formed ''in situ:'' :3 CH3OH + PI3 → 3 CH3I + H2PO3H Alternatively, it is prepared from the reaction of dimethyl sulfate with potassium iodide in the presence of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury(II) Chloride
Mercury(II) chloride (or mercury bichloride, mercury dichloride), historically also known as sulema or corrosive sublimate, is the inorganic chemical compound of mercury and chlorine with the formula HgCl2. It is white crystalline solid and is a laboratory reagent and a molecular compound that is very toxic to humans. Once used as a treatment for syphilis, it is no longer used for medicinal purposes because of mercury toxicity and the availability of superior treatments. Synthesis Mercuric chloride is obtained by the action of chlorine on mercury or on mercury(I) chloride. It can also be produced by the addition of hydrochloric acid to a hot, concentrated solution of mercury(I) compounds such as the nitrate: :Hg2(NO3)2 + 4 HCl → 2 HgCl2 + 2 H2O + 2 NO2 Heating a mixture of solid mercury(II) sulfate and sodium chloride also affords volatile HgCl2, which can be separated by sublimation. Process for synthesis of Mercuric chloride first appeared in Abu Bakr al-Razi's ''De ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetic Acid
Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component of vinegar apart from water and other trace elements. Acetic acid is the second simplest carboxylic acid (after formic acid). It is an important Reagent, chemical reagent and industrial chemical, used primarily in the production of cellulose acetate for photographic film, polyvinyl acetate for wood Adhesive, glue, and synthetic fibres and fabrics. In households, diluted acetic acid is often used in descaling agents. In the food industry, acetic acid is controlled by the E number, food additive code E260 as an acidity regulator and as a condiment. In biochemistry, the acetyl group, derived from acetic acid, is fundamental to all forms of life. When bound to coenzyme A, it is central to the metabolism of carbohydrates and fats. The global ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethyl Sulfoxide
Dimethyl sulfoxide (DMSO) is an organosulfur compound with the formula ( CH3)2. This colorless liquid is the sulfoxide most widely used commercially. It is an important polar aprotic solvent that dissolves both polar and nonpolar compounds and is miscible in a wide range of organic solvents as well as water. It has a relatively high boiling point. DMSO has the unusual property that many individuals perceive a garlic-like taste in the mouth after DMSO makes contact with their skin. In terms of chemical structure, the molecule has idealized Cs symmetry. It has a trigonal pyramidal molecular geometry consistent with other three-coordinate S(IV) compounds, with a nonbonded electron pair on the approximately tetrahedral sulfur atom. Synthesis and production Dimethyl sulfoxide was first synthesized in 1866 by the Russian scientist Alexander Zaytsev, who reported his findings in 1867. Dimethyl sulfoxide is produced industrially from dimethyl sulfide, a by-product of the Kraf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MTM Ether
MTM may refer to: Computing * Microsoft Test Manager, a diagnostic software tool Science, technology, medicine and engineering * Medication Therapy Management, pharmaceutical care by pharmacists * Methods-time measurement, a motion time system * Methyltrimethoxysilane, an organosilicon compound * Midwoofer-tweeter-midwoofer, a loudspeaker configuration * Model–test–model, in military combat modelling * Modified Transverse Mercator coordinate system, used in Eastern Canada * Motoren Technik Mayer, Wettstetten, Germany, a car tuner * Mountaintop removal mining * Methylthiomethyl ether * Myotubular myopathy or centronuclear myopathy, a muscle disorder * Massive Thirring Model, in quantum field theory * Mark-to-market accounting, or fair value accounting Entertainment * MTM Enterprises, Mary Tyler Moore's production company ** MTM Records, a MTM Enterprises record label * MTM (band), a Portuguese band Other * Media Technology Monitor (MTM), a Canadian survey * Momentum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
