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DMPU
''N'',''N''′-Dimethylpropyleneurea (DMPU) is a cyclic urea sometimes used as a polar, aprotic organic solvent. Along with the dimethylethyleneurea, it was introduced as an analog of tetramethylurea. In 1985, Dieter Seebach showed that it is possible to replace the suspected carcinogen hexamethylphosphoramide Hexamethylphosphoramide, often abbreviated HMPA, is a phosphoramide (an amide of phosphoric acid) with the formula This colorless liquid is used as a solvent in organic synthesis. Structure and reactivity HMPA is the oxide of tris(dimethyla ... (HMPA) with DMPU. References Further reading * * Solvents Green chemistry {{organic-compound-stub Amide solvents Amides Ureas Nitrogen heterocycles Heterocyclic compounds with 1 ring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexamethylphosphoramide
Hexamethylphosphoramide, often abbreviated HMPA, is a phosphoramide (an amide of phosphoric acid) with the formula This colorless liquid is used as a solvent in organic synthesis. Structure and reactivity HMPA is the oxide of tris(dimethylamino)phosphine, P(NMe2)3. Like other phosphine oxides (such as triphenylphosphine oxide), the molecule has a tetrahedral core and a P=O bond that is highly polarized, with significant negative charge residing on the oxygen atom. Compounds containing a nitrogen–phosphorus bond typically are degraded by hydrochloric acid to form a protonated amine and phosphate. It dissolves alkali metal salts and alkali metals, forming blue solutions which are stable for a few hours. Solvated electrons are present in these blue solutions. Applications HMPA is a specialty solvent for polymers, gases, and organometallic compounds. It improves the selectivity of lithiation reactions by breaking up the oligomers of lithium bases such as butyllithium. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylethyleneurea
1,3-Dimethyl-2-imidazolidinone (DMI) is a cyclic urea used as a high-boiling polar aprotic solvent. This colourless, highly polar solvent has high thermal and chemical stability. Together with homologous solvent DMPU, since the 1970s it serves as an analog of tetramethylurea. It can be prepared from 1,2-dimethylethylenediamine by reaction with phosgene. History In 1940 Du Pont applied for a patent on acetylene storage in many polar organic solvents, one of which was 1,3-dimethyl-2-imid azolidone. The company filed another patent on a method of synthesizing the same compound, albeit called s-dimethylethyleneurea, in 1944. Soon thereafter William Boon from the Imperial Chemical Industries published a different synthesis method of what he called 1:3-dimethyliminazolid-2-one. The compound was more closely studied in the 1960s, with its adoption as a solvent starting in the 1970s. Solvent DMI has excellent solvating ability for both inorganic and organic compounds. In many appli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvents
A solvent (from the Latin '' solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for polar molecules, and the most common solvent used by living things; all the ions and proteins in a cell are dissolved in water within the cell. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners (toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers (hexane, petrol ether); in detergents ( citrus terpenes); and in perfumes (ethanol). Solvents find various applications in chemical, pharmaceutical, oil, and gas industries, including in chemical syntheses and purification processes Some petrochemical solvents are highly toxic and emit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Aprotic Solvent
A polar aprotic solvent is a solvent that lacks an acidic proton and is polar. Such solvents lack hydroxyl and amine groups. In contrast to protic solvents, these solvents do not serve as proton donors in 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 b ..., although they can be proton acceptors. Many solvents, including chlorocarbons and hydrocarbons, are classifiable as aprotic, but polar aprotic solvents are of particular interest for their ability to dissolve salts. Methods for purification of common solvents are available. References * {{Chemical solutions Solvents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solvent
A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid. Water is a solvent for Chemical polarity#Polarity of molecules, polar molecules, and the most common solvent used by living things; all the ions and proteins in a Cell (biology), cell are dissolved in water within the cell. Major uses of solvents are in paints, paint removers, inks, and dry cleaning. Specific uses for Organic compound, organic solvents are in dry cleaning (e.g. tetrachloroethylene); as paint thinners (toluene, turpentine); as nail polish removers and solvents of glue (acetone, methyl acetate, ethyl acetate); in spot removers (hexane, petrol ether); in detergents (D-limonene, citrus terpenes); and in perfumes (ethanol). Solvents find various applications in chemical, pharmaceutical, oil, and gas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dieter Seebach
Dieter Seebach is a German chemist known for his synthesis of biopolymers and dendrimers, and for his contributions to stereochemistry. He was born on 31 October 1937 in Karlsruhe. He studied chemistry at the University of Karlsruhe (TH) under the supervision of Rudolf Criegee and at Harvard University with Elias Corey finishing in 1969. After his habilitation he became professor for organic chemistry at the University of Giessen. After six years he was appointed professor at the ETH Zurich where he worked until he retired in 2003. Work Seebach worked on dendrimer chemistry and on the synthesis of beta-peptides. The development of the umpolung, a polarity inversion of the carbonyl group, with 1,3-propanedithiol together with Corey had a big influence on organic synthesis, and subsequently the Corey-Seebach reaction was named after them. The Fráter–Seebach alkylation, a diastereoselective reaction of beta-hydroxy esters, is named after him. Awards *2000 Marcel Benoist P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Society Of Chemistry
The Royal Society of Chemistry (RSC) is a learned society and professional association in the United Kingdom with the goal of "advancing the chemistry, chemical sciences". It was formed in 1980 from the amalgamation of the Chemical Society, the Royal Institute of Chemistry, the Faraday Society, and the Society for Analytical Chemistry with a new Royal Charter and the dual role of learned society and professional body. At its inception, the Society had a combined membership of 49,000 in the world. The headquarters of the Society are at Burlington House, Piccadilly, London. It also has offices in Thomas Graham House in Cambridge (named after Thomas Graham (chemist), Thomas Graham, the first president of the Chemical Society) where ''RSC Publishing'' is based. The Society has offices in the United States, on the campuses of The University of Pennsylvania and Drexel University, at the University City Science Center in Philadelphia, Pennsylvania, in both Beijing and Shanghai, People' ... [...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] |
Amides
In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a compound with the general formula , where R, R', and R″ represent any group, typically organyl groups or hydrogen atoms. The amide group is called a peptide bond when it is part of the main chain of a protein, and an isopeptide bond when it occurs in a side chain, as in asparagine and glutamine. It can be viewed as a derivative of a carboxylic acid () with the hydroxyl group () replaced by an amino group (); or, equivalently, an acyl (alkanoyl) group () joined to an amino group. Common amides are formamide (), acetamide (), benzamide (), and dimethylformamide (). Some uncommon examples of amides are ''N''-chloroacetamide () and chloroformamide (). Amides are qualified as primary, secondary, and tertiary according to the number of acyl groups bounded to the nitrogen atom. Nomenclature The core of amides is called the amide group (specifically, carboxamide group). In the usual no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amide Solvents
In organic chemistry, an amide, also known as an organic amide or a carboxamide, is a chemical compound, compound with the general formula , where R, R', and R″ represent any group, typically organyl functional group, groups or hydrogen atoms. The amide group is called a peptide bond when it is part of the Polymer backbone, main chain of a protein, and an isopeptide bond when it occurs in a side chain, as in asparagine and glutamine. It can be viewed as a Derivative (chemistry), derivative of a carboxylic acid () with the hydroxyl group () replaced by an amino group (); or, equivalently, an acyl group, acyl (alkanoyl) group () joined to an amino group. Common amides are formamide (), acetamide (), benzamide (), and dimethylformamide (). Some uncommon examples of amides are ''N''-chloroacetamide () and chloroformamide (). Amides are qualified as primary (chemistry), primary, secondary (chemistry), secondary, and tertiary (chemistry), tertiary according to the number of acyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Green Chemistry
Green chemistry, similar to sustainable chemistry or circular chemistry, is an area of chemistry and chemical engineering focused on the design of products and processes that minimize or eliminate the use and generation of hazardous substances. While environmental chemistry focuses on the effects of pollutant, polluting chemicals on nature, green chemistry focuses on the environmentalism, environmental impact of chemistry, including lowering consumption of nonrenewable resources and technological approaches for preventing pollution. The overarching goals of green chemistry—namely, more resource-efficient and inherently safer design of molecules, materials, products, and processes—can be pursued in a wide range of contexts. History Green chemistry emerged from a variety of existing ideas and research efforts (such as atom economy and catalysis) in the period leading up to the 1990s, in the context of increasing attention to problems of chemical pollution and resource depletio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helvetica Chimica Acta
''Helvetica Chimica Acta'' is a peer-reviewed scientific journal of chemistry established by the Swiss Chemical Society. It is published online by John Wiley & Sons. The journal has a 2023 impact factor of 1.5. History *August 6, 1901: Founding of the Swiss Chemical Society *1911: IUPAC refused SCG as a member, no own journal *September 11, 1917: SCG founded HCA *1917–1948: First editor-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility for its operations and policies. The editor-in-chief heads all departments of the organization and is held accoun ...: Friedrich Fichter (1869–1952) *Spring 1918: Fasciculus I of Volume I of HCA was issued *1948–1971: Emile Cherbuliez (1891–1985) *1970: English allowed as fourth language *1971–1983: Edgardo Giovannini (1909–2004) *1983–2015: M. Volkan Kisakürek *2015-2016: Richard J. Smith *2016–2021: Jeffrey W. Bode and Christophe Copére ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
