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Quinaldine
Quinaldine or 2-methylquinoline is an organic compound with the formula CH3C9H6N. It is one of the methyl derivatives of the heterocyclic compound quinoline. It is bioactive and is used in the preparation of various dyes. It is a colorless oil but commercial samples can appear colored. Production and reactions Quinaldine is recovered from coal tar. It can be prepared from aniline and paraldehyde via Skraup synthesis or from aniline and crotonaldehyde via Doebner-von Miller variation of the Skraup reaction. Hydrogenation of quinaldine gives 2-methyltetrahydroquinoline. This reduction can be conducted enantioselectively. Properties Quinaldine has critical point at 787 K and 4.9 MPa and its refractive index In optics, the refractive index (or refraction index) of an optical medium is a dimensionless number that gives the indication of the light bending ability of that medium. The refractive index determines how much the path of light is bent, or ... is 1.8116. Uses Qui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Methyltetrahydroquinoline
2-Methyltetrahydroquinoline is one of the methyl-substituted derivatives of tetrahydroquinoline. A colorless oil, it is a chiral compound owing to the presence of the methyl substituent. It is produced by the hydrogenation of quinaldine. It is of interest in medicinal chemistry Medicinal or pharmaceutical chemistry is a scientific discipline at the intersection of chemistry and pharmacy involved with designing and developing pharmaceutical drugs. Medicinal chemistry involves the identification, synthesis and developm .... References {{DEFAULTSORT:Methyltetrahydroquinoline, 2- Tetrahydroquinolines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinoline Yellow SS
Quinoline Yellow SS is a bright yellow dye with green shade. It is insoluble in water, but soluble in nonpolar organic solvents. Quinoline yellow is representative of a large class of quinophthalone pigments. It is suggested that quinoline yellow exhibits excited-state intramolecular proton transfer (ESIPT) behavior and the behavior might be the cause of its decent photostability, by recent spectroscopic study. Synthesis and reactions As first described in 1878, the dye is prepared by the fusion of phthalic anhydride and quinaldine. The compound exists as a mixture of two tautomers. Using other anhydrides and other quinaldine derivatives other dyes in the quinophthalone family can be prepared. When sulfonated, it converts to a water-soluble derivative, Quinoline Yellow WS. Uses and safety Quinoline Yellow SS is used in spirit lacquers, polystyrene, polycarbonates, polyamides, acrylic resins, and to color hydrocarbon solvents. It is also used in externally applied drugs and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinoline
Quinoline is a heterocyclic aromatic organic compound with the chemical formula C9H7N. It is a colorless hygroscopic liquid with a strong odor. Aged samples, especially if exposed to light, become yellow and later brown. Quinoline is only slightly soluble in cold water but dissolves readily in hot water and most organic solvents. Quinoline itself has few applications, but many of its derivatives are useful in diverse applications. A prominent example is quinine, an alkaloid found in plants. Over 200 biologically active quinoline and quinazoline alkaloids are identified. 4-Hydroxy-2-alkylquinolines (HAQs) are involved in antibiotic resistance. Occurrence and isolation Quinoline was first extracted from coal tar in 1834 by German chemist Friedlieb Ferdinand Runge; he called quinoline ''leukol'' ("white oil" in Greek). Coal tar remains the principal source of commercial quinoline. In 1842, French chemist Charles Gerhardt obtained a compound by dry distilling quinine, stry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. 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, hydrogen cyanide), are not classified as organic compounds and are considered inorganic. Other than those just named, little consensus exists among chemists on precisely which carbon-containing compounds are excluded, making any rigorous definition of an organic compound elusive. Although organic compounds make up only a small percentage of Earth's crust, they are of central importance because all known life is based on organic compounds. Living t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pinacyanol
Pinacyanol is a cyanine dye. It is an organic cation, typically isolated as the chloride or iodide salts. The blue dye is prepared from 2-methylquinoline by quaternization with ethyl chloride or ethyl iodide. Condensation with formaldehyde results in coupling. Subsequent oxidation of the leuco intermediate gives the dye. Pinacyanol is a prototypical cyanine dye that was widely used as a sensitizer in electrophotography Xerography is a dry photocopying technique. Originally called electrophotography, it was renamed xerography—from the roots el, ξηρός, label=none ''xeros'', meaning "dry" and -γραφία ''-graphia'', meaning "writing"—to emphasize .... Its biological properties have also been investigated widely.{{cite journal , doi=10.1021/cb600362d, title=Inhibition of Angiogenesis by the Antifungal Drug Itraconazole, year=2007, last1=Chong, first1=Curtis R., last2=Xu, first2=Jing, last3=Lu, first3=Jun, last4=Bhat, first4=Shridhar, last5=Sullivan, first5=Davi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quinoline Yellow WS
Quinoline Yellow WS is a mixture of organic compounds derived from the dye Quinoline Yellow SS (spirit soluble). Owing to the presence of sulfonate groups, the WS dyes are water-soluble (WS). It is a mixture of disulfonates (principally), monosulfonates and trisulfonates of 2-(2-quinolyl)indan-1,3-dione with a maximum absorption wavelength of 416 nm.p. 119 Uses Quinoline Yellow is used as a greenish yellow food additive in certain countries, designated in Europe as the E number E104. In the EU and Australia, Quinoline Yellow is permitted in beverages and is used in foods, like sauces, decorations, and coatings; Quinoline Yellow is not listed as a permitted food additive in Canada or the US, where it is permitted in medicines and cosmetics and is known as D&C Yellow 10. The Codex Alimentarius does not list it. Health effects Quinoline Yellow WS has not been associated with any significant long-term toxicity, is not genotoxic or carcinogenic and there is no evidence o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Refractive Index
In optics, the refractive index (or refraction index) of an optical medium is a dimensionless number that gives the indication of the light bending ability of that medium. The refractive index determines how much the path of light is bent, or refracted, when entering a material. This is described by Snell's law of refraction, , where ''θ''1 and ''θ''2 are the angle of incidence and angle of refraction, respectively, of a ray crossing the interface between two media with refractive indices ''n''1 and ''n''2. The refractive indices also determine the amount of light that is reflected when reaching the interface, as well as the critical angle for total internal reflection, their intensity ( Fresnel's equations) and Brewster's angle. The refractive index can be seen as the factor by which the speed and the wavelength of the radiation are reduced with respect to their vacuum values: the speed of light in a medium is , and similarly the wavelength in that medium is , where '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Critical Point (thermodynamics)
In thermodynamics, a critical point (or critical state) is the end point of a phase equilibrium curve. The most prominent example is the liquid–vapor critical point, the end point of the pressure–temperature curve that designates conditions under which a liquid and its vapor can coexist. At higher temperatures, the gas cannot be liquefied by pressure alone. At the critical point, defined by a ''critical temperature'' ''T''c and a ''critical pressure'' ''p''c, phase boundaries vanish. Other examples include the liquid–liquid critical points in mixtures, and the ferromagnet–paramagnet transition (Curie temperature) in the absence of an external magnetic field. Liquid–vapor critical point Overview For simplicity and clarity, the generic notion of ''critical point'' is best introduced by discussing a specific example, the vapor–liquid critical point. This was the first critical point to be discovered, and it is still the best known and most studied one. The figu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogenation
Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a Catalysis, catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or Saturated and unsaturated compounds, saturate organic compounds. Hydrogenation typically constitutes the addition of pairs of hydrogen atoms to a molecule, often an alkene. Catalysts are required for the reaction to be usable; non-catalytic hydrogenation takes place only at very high temperatures. Hydrogenation reduces Double bond, double and Triple bond, triple bonds in hydrocarbons. Process Hydrogenation has three components, the Saturated and unsaturated compounds, unsaturated substrate, the hydrogen (or hydrogen source) and, invariably, a catalyst. The redox, reduction reaction is carried out at different temperatures and pressures depending upon the substrate and the activity of the catalyst. Related or competing reactions The same ca ... [...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 quinol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skraup Reaction
The Skraup synthesis is a chemical reaction used to synthesize quinolines. It is named after the Czech chemist Zdenko Hans Skraup (1850-1910). In the archetypal Skraup reaction, aniline is heated with sulfuric acid, glycerol, and an oxidizing agent such as nitrobenzene to yield quinoline. In this example, nitrobenzene serves as both the solvent and the oxidizing agent. The reaction, which otherwise has a reputation for being violent, is typically conducted in the presence of ferrous sulfate. Arsenic acid Arsenic acid or trihydrogen arsenate is the chemical compound with the formula . More descriptively written as , this colorless acid is the arsenic analogue of phosphoric acid. Arsenate and phosphate salts behave very similarly. Arsenic acid as ... may be used instead of nitrobenzene and the former is better since the reaction is less violent. See also * Bischler-Napieralski reaction * Doebner-Miller reaction References {{DEFAULTSORT:Skraup Reaction Condensatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
