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Martinet Dioxindole Synthesis
The Martinet dioxindole synthesis was first reported in 1913 by J. Martinet. It is a chemical reaction in which a primary or secondary aniline or substituted aromatic amine is condensed with ethyl or methyl ester of mesoxalic acid to make a dioxindole in the absence of oxygen. Proposed mechanism In the first step, the amino group on the aniline (1) attacks the carbonyl of the ethyl oxomalonate (2). A proton from the nitrogen is extracted by the oxygen and an alcohol group forms (3). The carbonyl re-forms to make a keto group and an ethanol molecule leaves (4). Next, a ring closing reaction occurs by the bond from the aromatic benzene ring attacking the partially positive carbonyl to form a five-member ring (5). After a proton transfer (6), an isomerization or a [1,3] hydride shift occurs and aromaticity is restored to the six-membered ring (7). In the presence of base, the ester is hydrolyzed, ethanol is lost (8) and a decarboxylation occurs (9). The resulting product is the de ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aniline
Aniline is an organic compound with the formula C6 H5 NH2. Consisting of a phenyl group attached to an amino group, aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans. Relative to benzene, it is electron-rich. It thus participates more rapidly in electrophilic aromatic substitution reactions. Likewise, it is also prone to oxidation: while freshly purified aniline is an almost colorless oil, exposure to air results in gradual darkening to yellow or red, due to the formation of strongly colored, oxidized impurities. Aniline can be diazotized to give a diazonium salt, which can then undergo vario ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation
Redox (reduction–oxidation, , ) is a type of chemical reaction in which the oxidation states of substrate change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is the gain of electrons or a decrease in the oxidation state. There are two classes of redox reactions: * ''Electron-transfer'' – Only one (usually) electron flows from the reducing agent to the oxidant. This type of redox reaction is often discussed in terms of redox couples and electrode potentials. * ''Atom transfer'' – An atom transfers from one substrate to another. For example, in the rusting of iron, the oxidation state of iron atoms increases as the iron converts to an oxide, and simultaneously the oxidation state of oxygen decreases as it accepts electrons released by the iron. Although oxidation reactions are commonly associated with the formation of oxides, other chemical species can serve the same function. In hydrogenation, C=C (and other) bond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxindole
Oxindole (2-indolone) is an aromatic heterocyclic organic compound with the formula C6H4CHC(O)NH. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered nitrogen-containing ring. Oxindole is a modified indoline with a substituted carbonyl at the second position of the 5-member indoline ring. Classified as a cyclic amide, it is a pale yellow solid. Formation and reactions Oxindole is derived in nature from tryptophan, formed by gut bacteria ("normal flora"). It is normally metabolized and detoxified from the body by the liver. In excess, it can cause sedation, muscle weakness, hypotension, and coma. Patients with hepatic encephalopathy have been recorded to have elevated serum oxindole levels. Treatment with phosphorus pentasulfide Phosphorus pentasulfide is the inorganic compound with the formula ( monomer) or ( dimer). This yellow solid is the one of two phosphorus sulfides of commercial value. Samples often appear greenish-gray du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indole
Indole is an aromatic heterocyclic organic compound with the formula C8 H7 N. It has a bicyclic structure, consisting of a six-membered benzene ring fused to a five-membered pyrrole ring. Indole is widely distributed in the natural environment and can be produced by a variety of bacteria. As an intercellular signal molecule, indole regulates various aspects of bacterial physiology, including spore formation, plasmid stability, resistance to drugs, biofilm formation, and virulence. The amino acid tryptophan is an indole derivative and the precursor of the neurotransmitter serotonin. General properties and occurrence Indole is a solid at room temperature. It occurs naturally in human feces and has an intense fecal odor. At very low concentrations, however, it has a flowery smell, and is a constituent of many perfumes. It also occurs in coal tar. The corresponding substituent is called indolyl. Indole undergoes electrophilic substitution, mainly at position 3 (see diagr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aromatic
In chemistry, aromaticity is a chemical property of cyclic (ring-shaped), ''typically'' planar (flat) molecular structures with pi bonds in resonance (those containing delocalized electrons) that gives increased stability compared to saturated compounds having single bonds, and other geometric or connective non-cyclic arrangements with the same set of atoms. Aromatic rings are very stable and do not break apart easily. Organic compounds that are not aromatic are classified as aliphatic compounds—they might be cyclic, but only aromatic rings have enhanced stability. The term ''aromaticity'' with this meaning is historically related to the concept of having an aroma, but is a distinct property from that meaning. Since the most common aromatic compounds are derivatives of benzene (an aromatic hydrocarbon common in petroleum and its distillates), the word ''aromatic'' occasionally refers informally to benzene derivatives, and so it was first defined. Nevertheless, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicyclic
In chemistry, a bicyclic molecule () is a molecule that features two joined rings. Bicyclic structures occur widely, for example in many biologically important molecules like α-thujene and camphor. A bicyclic compound can be carbocyclic (all of the ring atoms are carbons), or heterocyclic (the rings' atoms consist of at least two elements), like DABCO. Moreover, the two rings can both be aliphatic (''e.g.'' decalin and norbornane), or can be aromatic (''e.g.'' naphthalene), or a combination of aliphatic and aromatic (''e.g.'' tetralin). Three modes of ring junction are possible for a bicyclic compound: * In spirocyclic compounds, the two rings share only one single atom, the spiro atom, which is usually a quaternary carbon. An example of a spirocyclic compound is the photochromic switch spiropyran. * In fused/condensed bicyclic compounds, two rings share two adjacent atoms. In other words, the rings share one covalent bond, ''i.e.'' the so-called bridgehead atoms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterocyclic
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 quinol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Martinet Dioxindole Synthesis With Alkoxy Aniline And Oxomalonic Ester
The martinet (OED ''s.v.'' ''martinet'', ''n.''2, "'' N.E.D.'' (1905) gives the pronunciation as (mā·ɹtinėt) /ˈmɑːtɪnɪt/ .") is a punitive device traditionally used in France and other parts of Europe. The word also has other usages, described below. Object A martinet is a short, scourge-like (multi-tail) type of whip made of a wooden handle of about 25 cm (10 inches) in length and about 10 lashes of equal, relatively short length. The lashes are usually made of leather, but sometimes soap-stiffened cords are used in place of leather. It was a traditional instrument of physical punishment in France and other European countries. In French, it also refers to a similar dusting implement; the type for chastisement was also known as ''fouet d'enfant'', meaning ''child's whip''. The lashes are light, so they are ineffective unless the child is whipped naked. The advantage is they give a stinging pain on bare skin, but will not cause an injury. Person In French The term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitroalkene
A nitroalkene, or nitro olefin, is a functional group combining the functionality of its constituent parts, an alkene and nitro group, while displaying its own chemical properties through alkene activation, making the functional group useful in specialty reactions such as the Michael reaction or Diels-Alder additions. Synthesis Nitroalkenes are synthesized by various means, notable examples include: * Nitroaldol reactions such as the Henry reaction: : * Nitration of an alkene with nitryl iodide generated ''in-situ'' from silver nitrite and elemental iodine: * Direct nitration of alkenes with nitric oxide and an aluminum oxide catalyst in acidic conditions: *Direct nitration of alkenes with Clayfen ( Iron(III) nitrate supported on Montmorillonite clay): * Dehydration of nitro-alcohols: Reactions Nitroalkenes are useful intermediates for various chemical functionalities. * A nitroalkene behaving as a Michael acceptor in the synthesis of Lycoricidine: * Nitroalkene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Michael Addition
In organic chemistry, the Michael reaction or Michael addition is a reaction between a Michael donor (an enolate or other nucleophile) and a Michael acceptor (usually an α,β-unsaturated carbonyl) to produce a Michael adduct by creating a carbon-carbon bond at the acceptor's β-carbon. It belongs to the larger class of conjugate additions and is widely used for the mild formation of carbon-carbon bonds. The Michael addition is an important atom-economical method for diastereoselective and enantioselective C–C bond formation, and many asymmetric variants exist : In this general Michael addition scheme, either or both of R and R' on the nucleophile (the Michael donor) represent electron-withdrawing substituents such as acyl, cyano, nitro, or sulfone groups, which make the adjacent methylene hydrogen acidic enough to form a carbanion when reacted with the base, ''B:''. For the alkene (the Michael acceptor), the R" substituent is usually a carbonyl, which makes the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isatin
Isatin, also known as tribulin, is an organic compound derived from indole with formula C8H5NO2. The compound was first obtained by Otto Linné Erdman and Auguste Laurent in 1840 as a product from the oxidation of indigo dye by nitric acid and chromic acids. Isatin is a well-known natural product which can be found in plants of the genus '' Isatis'', in '' Couroupita guianensis'', and also in humans, as a metabolic derivative of adrenaline. It looks like a red-orange powder, and it is usually employed as building block for the synthesis of a wide variety of biologically active compounds including antitumorals, antivirals, anti-HIVs, and antituberculars. The isatin core is also responsible for the color of “ Maya blue” and “Maya yellow” dyes. Synthesis Sandmeyer methodology The Sandmeyer methodology is the oldest and straightforward way for the synthesis of isatin. The method involves the condensation between chloral hydrate and a primary arylamine (e.g. ani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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