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Thiophene-2-carboxylic Acid
Thiophene-2-carboxylic acid is an organic compound with the formula SC4H3CO2H. It is one of two monocarboxylic acids of thiophene, the other being thiophene-3-carboxylic acid. Copper(I) thiophene-2-carboxylate is a catalyst for Ullmann coupling reactions. Synthesis It can be prepared by the oxidation of thiophene-2-carboxaldehyde or, more practically, 2-acetylthiophene.. Applications and reactions left, Suprofen, which is produced from thiophene-2-carboxylic acid, is the active ingredient in some eye drops. Upon treatment with lithium diisopropylamide, LDA, thiophene-2-carboxylic acid undergoes double deprotonation to give the 5-lithio derivative, a precursor to many 5-substituted derivatives. Thiophene-2-carboxylic acid has been widely studied as a substrate in coupling reaction A coupling reaction in organic chemistry is a general term for a variety of reactions where two fragments are joined together with the aid of a metal catalyst. In one important reaction type, a mai ... [...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] |
Carboxylic Acid
In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic acids occur widely. Important examples include the amino acids and fatty acids. Deprotonation of a carboxylic acid gives a carboxylate anion. Examples and nomenclature Carboxylic acids are commonly identified by their trivial names. They at oftentimes have the suffix ''-ic acid''. IUPAC-recommended names also exist; in this system, carboxylic acids have an ''-oic acid'' suffix. For example, butyric acid (C3H7CO2H) is butanoic acid by IUPAC guidelines. For nomenclature of complex molecules containing a carboxylic acid, the carboxyl can be considered position one of the parent chain even if there are other substituents, such as 3-chloropropanoic acid. Alternately, it can be named as a "carboxy" or "carboxylic acid" substituent on another ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiophene
Thiophene is a heterocyclic compound with the formula C4H4S. Consisting of a planar five-membered ring, it is aromatic as indicated by its extensive substitution reactions. It is a colorless liquid with a benzene-like odor. In most of its reactions, it resembles benzene. Compounds analogous to thiophene include furan (C4H4O), selenophene (C4H4Se) and pyrrole (C4H4NH), which each vary by the heteroatom in the ring. Isolation and occurrence Thiophene was discovered as a contaminant in benzene. It was observed that isatin (an indole) forms a blue dye if it is mixed with sulfuric acid and crude benzene. The formation of the blue indophenin had long been believed to be a reaction of benzene itself. Viktor Meyer was able to isolate thiophene as the actual substance responsible for this reaction. Thiophene and especially its derivatives occur in petroleum, sometimes in concentrations up to 1–3%. The thiophenic content of oil and coal is removed via the hydrodesulfurization (HDS) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(I) Thiophene-2-carboxylate
Copper(I) thiophene-2-carboxylate or CuTC is a coordination complex derived from copper and thiophene-2-carboxylic acid. It is used as a reagent to promote the Ullmann reaction between aryl halide In chemistry, a halide (rarely halogenide) is a binary chemical compound, of which one part is a halogen atom and the other part is an element or radical that is less electronegative (or more electropositive) than the halogen, to make a fluor ...s. : References {{reflist Thiophenes Copper(I) compounds Reagents for organic chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ullmann Reaction
The Ullmann reaction or Ullmann coupling is a coupling reaction between aryl halides. Traditionally this reaction is effected by copper, but palladium and nickel are also effective catalysts. The reaction is named after Fritz Ullmann. Mechanism The mechanism of the Ullmann reaction is extensively studied. Complications arise because the reactions are often heterogeneous. With copper as the halide acceptor, organocopper intermediates are invoked. Scope A typical example of classic Ullmann biaryl coupling is the conversion of ''ortho''-chloronitrobenzene into 2,2'-dinitrobiphenyl with a copper - bronze alloy. : : The traditional version of the Ullmann reaction requires harsh reaction conditions, and the reaction has a reputation for erratic yields. Because of these problems many improvements and alternative procedures have been introduced. The classical Ullmann reaction is limited to electron deficient aryl halides and requires harsh reaction conditions. Modern variants of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiophene-2-carboxaldehyde
Thiophene-2-carboxaldehyde is an organosulfur compound with the formula C4H3SCHO. It is one of two isomeric thiophenecarboxaldehydes. It is a colorless liquid that often appears amber after storage. It is versatile precursor to many drugs including eprosartan, Azosemide, and Teniposide. Preparation It can be prepared from thiophene Thiophene is a heterocyclic compound with the formula C4H4S. Consisting of a planar five-membered ring, it is aromatic as indicated by its extensive substitution reactions. It is a colorless liquid with a benzene-like odor. In most of its reacti ... by the Vilsmeier reaction. Alternatively, it is prepared from chloromethylation of thiophene. References {{reflist Thiophenes Aldehydes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2-Acetylthiophene
2-Acetylthiophene is an organosulfur compound with the formula CH3C(O)C4H3S. A yellow liquid, it is the more useful of the two isomers of acetylthiophene. It is of commercial interest as a precursor to both thiophene-2-carboxylic acid and thiophene-2-acetic acid. It is prepared by the reaction of thiophene with acetyl chloride in the presence of stannic chloride Tin(IV) chloride, also known as tin tetrachloride or stannic chloride, is an inorganic compound with the formula Sn Cl4. It is a colorless hygroscopic liquid, which fumes on contact with air. It is used as a precursor to other tin compounds. It .... References {{DEFAULTSORT:Acetylthiophene, 2- Thiophenes Carboxylic acids ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suprofen
Suprofen is a nonsteroidal anti-inflammatory drug (NSAID) developed by Janssen Pharmaceutica that was marketed as 1% eye drops under the trade name Profenal. Uses Suprofen was originally used as tablet, but oral uses have been discontinued due to renal effects. It was subsequently used exclusively as a topical ophthalmic solution, typically to prevent miosis during and after ophthalmic surgery Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pat .... This application has been discontinued as well, at least in the US. References Nonsteroidal anti-inflammatory drugs Thiophenes Propionic acids Aromatic ketones Janssen Pharmaceutica {{musculoskeletal-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithium Diisopropylamide
Lithium diisopropylamide (commonly abbreviated LDA) is a chemical compound with the molecular formula . It is used as a strong base and has been widely utilized due to its good solubility in non-polar organic solvents and non-nucleophilic nature. It is a colorless solid, but is usually generated and observed only in solution. It was first prepared by Hamell and Levine in 1950 along with several other hindered lithium diorganylamides to effect the deprotonation of esters at the α position without attack of the carbonyl group. Preparation and structure LDA is commonly formed by treating a cooled (0 to −78 °C) mixture of tetrahydrofuran and diisopropylamine with ''n''-butyllithium. When dissociated, the diisopropylamide anion can become protonated to form diisopropylamine. Diisopropylamine has a p''K''a value of 36. Therefore, its conjugate base is suitable for the deprotonation of compounds with greater acidity, importantly, such weakly acidic compounds (carbon acids) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coupling Reaction
A coupling reaction in organic chemistry is a general term for a variety of reactions where two fragments are joined together with the aid of a metal catalyst. In one important reaction type, a main group organometallic compound of the type R-M (R = organic fragment, M = main group center) reacts with an organic halide of the type R'-X with formation of a new carbon-carbon bond in the product R-R'. The most common type of coupling reaction is the cross coupling reaction. Richard F. Heck, Ei-ichi Negishi, and Akira Suzuki were awarded the 2010 Nobel Prize in Chemistry for developing palladium-catalyzed cross coupling reactions. Broadly speaking, two types of coupling reactions are recognized: *Heterocouplings combine two different partners, such as in the Heck reaction of an alkene (RC=CH) and an alkyl halide (R'-X) to give a substituted alkene, or the Corey–House synthesis of an alkane by the reaction of a lithium diorganylcuprate (R2CuLi) with an organyl (pseudo)halide (R'X ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thiophenes
Thiophene is a heterocyclic compound with the formula C4H4S. Consisting of a planar five-membered ring, it is aromatic as indicated by its extensive substitution reactions. It is a colorless liquid with a benzene-like odor. In most of its reactions, it resembles benzene. Compounds analogous to thiophene include furan (C4H4O), selenophene (C4H4Se) and pyrrole (C4H4NH), which each vary by the heteroatom in the ring. Isolation and occurrence Thiophene was discovered as a contaminant in benzene. It was observed that isatin (an indole) forms a blue dye if it is mixed with sulfuric acid and crude benzene. The formation of the blue indophenin had long been believed to be a reaction of benzene itself. Viktor Meyer was able to isolate thiophene as the actual substance responsible for this reaction. Thiophene and especially its derivatives occur in petroleum, sometimes in concentrations up to 1–3%. The thiophenic content of oil and coal is removed via the hydrodesulfurization (HDS) pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
