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2-Benzimidazolinone
Benzimidazolinone is an organic compound with the formula . Also classified as a heterocyclic compound it is a bicyclic urea. It is a tautomer of 2-hydroxybenzimidazole. Synthesis, structure, applications The parent compound is prepared by the carbonylation of 1,2-diaminobenzene. The carbonylation can be effected with carbonyldiimidazole. Like other ureas, it engages in hydrogen bonding, yielding supramolecular structures. Otherwise, the compound is of little interest. Substituted 2-benzimidazolinones are commercial dyes and pigments. For example 4-amino-2-benzimidazolinone condenses with diketene to give the acetoacetanilide, which undergoes diazo coupling with various aryldiazonium salts. In this way pigment orange 36 and pigment yellow 154 are produced. These pigments are used in paints and plastics.{{cite book , doi=10.1002/0471238961.151807011001060605.a01.pub2 , chapter=Pigments, Organic , title=Kirk-Othmer Encyclopedia of Chemical Technology , date=2004 , last1=J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Domperidone
Domperidone, sold under the brand name Motilium among others, is a dopamine antagonist medication which is used to treat nausea and vomiting and certain gastrointestinal problems like gastroparesis (delayed gastric emptying). It raises the level of prolactin in the human body and is used off label to induce and promote breast milk production. It may be taken by mouth or rectally. Side effects may include headache, anxiety, dry mouth, abdominal cramps, diarrhea, and elevated prolactin levels. Secondary to increased prolactin levels, breast changes, milk outflow, menstrual irregularities, and hypogonadism can occur. Domperidone may also cause QT prolongation and has rarely been associated with serious cardiac complications such as sudden cardiac death. However, the risks are small and occur more with high doses. Domperidone acts as a peripherally selective antagonist of the dopamine D2 and D3 receptors. Due to its low entry into the brain, the side effects of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-containing compounds such as alkanes (e.g. methane ) and its derivatives are universally considered organic, but many others are sometimes considered inorganic, such as certain compounds of carbon with nitrogen and oxygen (e.g. cyanide ion , hydrogen cyanide , chloroformic acid , carbon dioxide , and carbonate ion ). Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The study of the properties, reactions, and syntheses of organic compounds comprise the discipline known as organic chemistry. For historical reasons, a few classes of carbon-containing compounds (e.g., carbonate salts and cyanide salts), along with a few other exceptions (e.g., carbon dioxide, and even ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pigment
A pigment is a powder used to add or alter color or change visual appearance. Pigments are completely or nearly solubility, insoluble and reactivity (chemistry), chemically unreactive in water or another medium; in contrast, dyes are colored substances which are soluble or go into solution at some stage in their use. Dyes are often organic compounds whereas pigments are often inorganic compound, inorganic. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli. Economic impact In 2006, around 7.4 million tons of inorganic chemistry, inorganic, organic chemistry, organic, and special pigments were marketed worldwide. According to an April 2018 report by ''Bloomberg Businessweek'', the estimated value of the pigment industry globally is $30 billion. The value of titanium dioxide – used to enhance the white brightness of many products – was placed at $13.2 billion per year, while the color Ferrari red is valued at $300 million each yea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Pigments
Organic may refer to: * Organic, of or relating to an organism, a living entity * Organic, of or relating to an anatomical organ Chemistry * Organic matter, matter that has come from a once-living organism, is capable of decay or is the product of decay, or is composed of organic compounds * Organic compound, a compound that contains carbon ** Organic chemistry, chemistry involving organic compounds Farming, certification and products * Organic farming, agriculture conducted according to certain standards, especially the use of stated methods of fertilization and pest control * Organic certification, accreditation process for producers of organically-farmed products * Organic horticulture, the science and art of growing fruits, vegetables, flowers, or ornamental plants by following the essential principles of organic agriculture * Organic products, "organics": ** Organic food, food produced from organic farming methods and often certified organic according to organic farming stan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ureas
image:Biotin_structure.svg, 220 px, Biotin, a water-soluble B vitamins, B vitamin, is a bicyclic urea. In chemistry, ureas are a class of organic compounds with the formula (R2N)2CO where R = H, alkyl, aryl, etc. Thus, in addition to describing the specific chemical compound urea ((H2N)2CO), urea is the name of a functional group that is found in many compounds and materials of both practical and theoretical interest. Generally ureas are colorless crystalline solids, which, owing to the presence of fewer hydrogen bonds, exhibit melting points lower than that of urea itself. Synthesis Ureas can be prepared many methods, but rarely by direct carbonation, which is the route to urea itself. Instead, methods can be classified according those that assemble the urea functionality and those that start with preformed urea. Assembly of N-substituted urea functionality Phosgenation entails the reaction of amines with phosgene, proceeding via the isocyanate (or carbamoyl chloride) as an i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aryldiazonium Salt
Benzenediazonium tetrafluoroborate is an organic compound with the formula 6H5N2F4. It is a salt of a diazonium cation and tetrafluoroborate. It exists as a colourless solid that is soluble in polar solvents. It is the parent member of the aryldiazonium compounds, which are widely used in organic chemistry. Synthesis Diazotization of aniline: : C6H5NH2 + HNO2 (from NaNO2 and HCl) + HCl → 6H5N2l + 2 H2O The tetrafluoroborate can be obtained from crude benzenediazonium chloride by salt metathesis using tetrafluoroboric acid. : 6H5N2l + HBF4 → 6H5N2F4 + HCl The tetrafluoroborate is more stable than the chloride. Properties The diazo group (N2) can be replaced by many other groups, usually anions, giving a variety of substituted phenyl derivatives: :C6H5N2+ + Nu− → C6H5Nu + N2 These transformations are associated with many named reactions including the Schiemann reaction, Sandmeyer reaction, and Gomberg–Bachmann reaction. A wide range of groups that can be used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetoacetanilide
Acetoacetanilide is an organic compound with the formula CH3C(O)CH2C(O)NHC6H5. It is the acetoacetamide derivative of aniline. It is a white solid that is poorly soluble in water. This chemical and many related compounds (prepared from various aniline derivatives) are used in the production of organic pigments called arylide yellows, one example being Pigment Yellow 74. Structure Acetoacetanilide crystallizes as the keto-amide tautomer according to X-ray crystallography. The molecules are linked by intermolecular hydrogen bonds, which allows the benzoyl ketone to rotate out of the plane of the amide. For the general case of ''substituted'' acetoanilides, substituents on the aryl ring affect the balance of intra- vs intermolecular hydrogen bonding. The situation is illustrated by the 2' vs. 3' vs. 4' fluoro-substituted acetoacetanilides. Preparation and reactions Acetoacetanilide is prepared by acetoacetylation of aniline using diketene. Many analogues have been prepar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diketene
Diketene is an organic compound with the molecular formula , and which is sometimes written as . It is formed by dimerization of ketene, . Diketene is a member of the oxetane family. It is used as a reagent in organic chemistry. It is a colorless liquid. Production Diketene is produced on commercial scale by dimerization of ketene. Reactions Heating or irradiation with UV light regenerates the ketene monomer: : Alkylated ketenes also dimerize with ease and form substituted diketenes. Diketene readily hydrolyzes in water forming acetoacetic acid. Its half-life in water is approximately 45 min. a 25 °C at . Certain diketenes with two aliphatic chains, such as alkyl ketene dimers (AKDs), are used industrially to improve hydrophobicity in paper. At one time acetic anhydride was prepared by the reaction of ketene with acetic acid: : ΔH = −63 kJ/mol Acetoacetylation Diketene also reacts with alcohols and amines to the corresponding acetoacetic acid deri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supramolecular
Supramolecular chemistry refers to the branch of chemistry concerning chemical systems composed of a discrete number of molecules. The strength of the forces responsible for spatial organization of the system range from weak intermolecular forces, electrostatic charge, or hydrogen bonding to strong covalent bonding, provided that the electronic coupling strength remains small relative to the energy parameters of the component. While traditional chemistry concentrates on the covalent bond, supramolecular chemistry examines the weaker and reversible non-covalent interactions between molecules. These forces include hydrogen bonding, metal coordination, hydrophobic forces, van der Waals forces, pi–pi interactions and electrostatic effects. Important concepts advanced by supramolecular chemistry include molecular self-assembly, molecular folding, molecular recognition, host–guest chemistry, mechanically-interlocked molecular architectures, and dynamic covalent chemistry. The ... [...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 organic chemistry is the branch of organic chemistry dealing with the synthesis, properties, and applications of organic 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 organic heterocyclic chemistry focuses especially on organic unsaturated derivatives, and the preponderance of work and applications involves unstrained organic 5- and 6-membered rings. Included are pyridine, thiophene, pyrrole, and furan. Another large class of organic heterocycles refers to those fused to benzene rings. For example, the fused benzene derivatives of py ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Bonding
In chemistry, a hydrogen bond (H-bond) is a specific type of molecular interaction that exhibits partial covalent character and cannot be described as a purely electrostatic force. It occurs when a hydrogen (H) atom, Covalent bond, covalently bonded to a more Electronegativity, electronegative donor atom or group (Dn), interacts with another electronegative atom bearing a lone pair of electrons—the hydrogen bond acceptor (Ac). Unlike simple Dipole–dipole attraction, dipole–dipole interactions, hydrogen bonding arises from charge transfer (nB → σ*AH), Atomic orbital, orbital interactions, and quantum mechanical Delocalized electron, delocalization, making it a resonance-assisted interaction rather than a mere electrostatic attraction. The general notation for hydrogen bonding is Dn−H···Ac, where the solid line represents a polar covalent bond, and the dotted or dashed line indicates the hydrogen bond. The most frequent donor and acceptor atoms are nitrogen (N), oxyg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonyldiimidazole
1,1'-Carbonyldiimidazole (CDI) is an organic compound with the molecular formula . It is a white crystalline solid. It is often used for the coupling of amino acids for peptide synthesis and as a reagent in organic synthesis. Preparation CDI can be prepared straightforwardly by the reaction of phosgene with four equivalents of imidazole under anhydrous conditions. Removal of the side product, imidazolium chloride, and solvent results in the crystalline product in ~90% yield. : In this conversion, the imidazole serves both as the nucleophile and the base. An alternative precursor 1-(trimethylsilyl)imidazole requires more preparative effort with the advantage that the coproduct trimethylsilyl chloride is volatile. CDI hydrolyzes readily to give back imidazole: : The purity of CDI can be determined by the amount of that is formed upon hydrolysis. Use in synthesis CDI is mainly employed to convert amines into amides, carbamates, ureas. It can also be used to convert alcohols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
