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Methylene Dinitrate
Methylene may refer to: * Methylene group or methylene bridge (CH2< or equivalently −CH2−), a part of a molecule connected to the rest of the molecule by two single bonds. * An older name for Methylidene#Methylidene group, methylidene group (=CH2), a part of a molecule connected to another atom by a double bond. * Methylene (compound) (CH2), an organic compound. See also * Bichloride of methylene (30% methanol and 70% chloroform), a variant of the old anesthetic A.C.E. mixture * Methyl group * Methylenedioxy * Mytilene, a city in Greece * Methanol {{disambiguation de:Methylengruppe sv:Metylengrupp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylene Group
A methylene group is any part of a molecule that consists of two hydrogen atoms bound to a carbon Carbon () is a chemical element; it has chemical symbol, symbol C and atomic number 6. It is nonmetallic and tetravalence, tetravalent—meaning that its atoms are able to form up to four covalent bonds due to its valence shell exhibiting 4 ... atom, which is connected to the remainder of the molecule by two single bonds. The group may be represented as or , where the '>' denotes the two bonds. This stands in contrast to a situation where the carbon atom is bound to the rest of the molecule by a double bond, which is preferably called a methylidene group, represented . Formerly the methylene name was used for both isomers. The name “ methylene bridge“ can be used for the single-bonded isomer, to emphatically exclude methylidene. The distinction is often important, because the double bond is chemically different from two single bonds. The methylene group should be d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylene Bridge
In chemistry, a methylene bridge is part of a molecule with formula . The carbon atom is connected by single bonds to two other distinct atoms in the rest of the molecule. A methylene bridge is often called a methylene group or simply methylene, as in "methylene chloride" (dichloromethane ). As a bridge in other compounds, for example in cyclic compounds, it is given the name methano. However, the term methylidene group (not to be confused with the term methylene group, nor the carbene Methylene (compound), methylidene) properly applies to the group when it is connected to the rest of the molecule by a double bond (), giving it chemical properties very distinct from those of a bridging group. Organic chemistry It is the repeating unit in the skeleton of the unbranched alkanes. Polyethylene also can be called polymethylene. Compounds possessing a methylene bridge located between two electron withdrawing groups (such as Nitro compound, nitro, carbonyl or nitrile groups) are som ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methylidene
Methylene (IUPAC name: methylidene, also called carbene or methene) is an organic compound with the chemical formula (also written and not to be confused with compressed hydrogen, which is also denoted ). It is a colourless gas that fluoresces in the mid-infrared range, and only persists in dilution, or as an adduct. Methylene is the simplest carbene.Roald Hoffman (2005), ''Molecular Orbitals of Transition Metal Complexes''. Oxford. . It is usually detected only at very low temperatures or as a short-lived intermediate in chemical reactions.W. B. DeMore and S. W. Benson (1964), Preparation, properties, and reactivity of methylene'. In ''Advances in Photochemistry'', John Wiley & Sons, 453 pages. Nomenclature The trivial name ''carbene'' is the preferred IUPAC name. The systematic names ''methylidene'' and ''dihydridocarbon'', valid IUPAC names, are constructed according to the substitutive and additive nomenclatures, respectively. ''Methylidene'' is viewed as methane with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bichloride Of Methylene
ACE mixture is an historical anaesthetic agent for general anaesthesia. It was first suggested by George Harley and first used in England around 1860. In 1864 it was recommended for use by the Royal Medical and Surgical Society's Chloroform Committee. It was rarely used after the 19th century, except in Germany, where it was used for slightly longer. It was a mixture of alcohol, chloroform and ether which gives the mixture its name. Its effects were said to be between that of chloroform and ether and it was used when ether alone was contraindicated. Its boiling point was given as . Its actual safety margin over its components alone was marginal. Usage ACE mixture was most commonly made up in the ratio: 1 part alcohol, 2 parts chloroform, and 3 parts ether although other ratios existed. See ' other preparations' below. Chloroform (which was first used in 1847) used on its own produces myocardial depression, however the excitatory properties of the alcohol and ether contained wi ... [...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] |
Methylenedioxy
Methylenedioxy is the term used in the field of chemistry, particularly in organic chemistry, for a functional group with the structural formula which is connected to the rest of a molecule by two chemical bonds. The methylenedioxy group consists of two oxygen atoms connected to a methylene bridge ( unit). The methylenedioxy group is generally found attached to an aromatic structure such as phenyl where it forms the methylenedioxyphenyl or benzodioxole functional group which is widely found in natural products, including safrole, and drugs and chemicals such as tadalafil, MDMA, paroxetine and piperonyl butoxide. Enzymes within the cytochrome P450 superfamily are able to form methylenedioxy bridges by closure of an open, adjacent phenol and methoxy group. Examples of products formed by this process are canadine and berberine. Similarly, ''ortho''-demethylenation can be carried out by other members of the superfamily to open a bridge; a process which is applied to, as examples, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mytilene
Mytilene (; ) is the capital city, capital of the Greece, Greek island of Lesbos, and its port. It is also the capital and administrative center of the North Aegean Region, and hosts the headquarters of the University of the Aegean. It was founded in the 11th century BC. Mytilene is one of the two municipalities and communities of Greece, municipalities on the island of Lesbos, created in 2019; the other is West Lesbos. Mytilene is built on the southeast edge of the island. It is the seat of a metropolitan bishop of the Greek Orthodox Church. History As an ancient city, lying off the east coast, Mytilene was initially confined to a small island just offshore that later was joined to Lesbos, creating a north and south harbor. The early harbors of Mytilene were linked during ancient times by a channel 700 m long and 30 m wide. The Roman writer Longus speaks of white stone bridges linking the two sides. The Greek word εὔριπος ''eúripos'' is a commonly-used term when ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methanol
Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical compound and the simplest aliphatic Alcohol (chemistry), alcohol, with the chemical formula (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is a light, Volatility (chemistry), volatile, colorless and flammable liquid with a distinctive alcoholic odor similar to that of ethanol (potable alcohol), but is more acutely toxic than the latter. Methanol acquired the name wood alcohol because it was once produced through destructive distillation of wood. Today, methanol is mainly produced industrially by hydrogenation of carbon monoxide. Methanol consists of a methyl group linked to a polar hydroxyl group. With more than 20 million tons produced annually, it is used as a Precursor (chemistry), precursor to other commodity chemicals, including formaldehyde, acetic acid, methyl tert-butyl ether, methyl ''tert''-butyl ether, methyl benzoate, anisole, peroxyacids, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
