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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] |
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] |
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] |
Homologous Series
In organic chemistry, a homologous series is a sequence of compounds with the same functional group and similar chemical properties in which the members of the series differ by the number of repeating units they contain. This can be the length of a carbon chain, for example in the straight-chained alkanes (paraffins), or it could be the number of monomers in a homopolymer such as amylose. A homologue (also spelled as homolog) is a chemical compound, compound belonging to a homologous series. Compounds within a homologous series typically have a fixed set of functional groups that gives them similar chemical and physical properties. (For example, the series of primary straight-chained alcohols has a hydroxyl at the end of the carbon chain.) These properties typically change gradually along the series, and the changes can often be explained by mere differences in molecular size and mass. The name "homologous series" is also often used for any collection of compounds that have similar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Tetramethylurea
Tetramethylurea is the organic compound with the formula (Me2N)2CO. It is a substituted ureas, urea. This colorless liquid is used as an Protic solvent, aprotic-polar solvent, especially for aromatic compounds and is used e. g. for Grignard reagents. Tetramethylurea is a colorless liquid with mild aromatic odor. Unusual for an urea is the liquid state of tetramethylurea in a range of > 170 °C. Production It is obtained by the reaction of dimethylamine with phosgene in the presence of sodium hydroxide solution. A closely related method combines dimethylcarbamoyl chloride with excess dimethylamine. This reactions is highly exothermic. The removal of the resulting dimethylamine hydrochloride requires some effort. The reaction of diphenylcarbonate with dimethylamine in an autoclave is also effective. Tetramethylurea is formed upon the oxygenation of tetrakis(dimethylamino)ethylene (TDAE). Tetramethylurea is also a common by-product formed in Amide, amide bond fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-Dimethylethylenediamine
N,N'-Dimethylethylenediamine (DMEDA) is the organic compound with the formula (CHNH)CH. It is a colorless liquid with a fishy odor. It features two secondary amine functional groups. Regarding its name, N and N' indicate that the methyl groups are attached to different nitrogen atoms. Reactions DMEDA is used as a chelating diamine for the preparation of metal complexes, some of which function as homogeneous catalysts. The compound is used as a precursor to imidazolidines by condensation with ketones or with aldehydes: : DMEDA complexes of copper(I) halides are used to catalyze C-N coupling reactions. See also * 1,1-Dimethylethylenediamine * Dimethylaminopropylamine Dimethylaminopropylamine (DMAPA) is a diamine used in the preparation of some surfactants, such as cocamidopropyl betaine which is an ingredient in many personal care products including soaps, shampoos, and cosmetics. BASF, a major producer, clai ... References {{DEFAULTSORT:Dimethylethylenediamine, 1, 2- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosgene
Phosgene is an organic chemical compound with the formula . It is a toxic, colorless gas; in low concentrations, its musty odor resembles that of freshly cut hay or grass. It can be thought of chemically as the double acyl chloride analog of carbonic acid, or structurally as formaldehyde with the hydrogen atoms replaced by chlorine atoms. In 2013, about 75–80 % of global phosgene was consumed for isocyanates, 18% for polycarbonates and about 5% for other fine chemicals. Phosgene is extremely poisonous and was used as a chemical weapon during World War I, where it was responsible for 85,000 deaths. It is a highly potent pulmonary irritant and quickly filled enemy trenches due to it being a heavy gas. It is classified as a Schedule 3 substance under the Chemical Weapons Convention. In addition to its industrial production, small amounts occur from the breakdown and the combustion of organochlorine compounds, such as chloroform. Structure and basic properties Phosgene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DuPont
Dupont, DuPont, Du Pont, duPont, or du Pont may refer to: People * Dupont (surname) Dupont, also spelled as DuPont, duPont, Du Pont, or du Pont is a French surname meaning "of the bridge", historically indicating that the holder of the surname resided near a bridge. , the name was the fourth most popular surname in Belgium, and , i ..., a surname of French origin * Du Pont family, one of the wealthiest families in the United States Companies * DuPont, one of the world's largest chemical companies * Du Pont Motors, a marine engine and automobile manufacturer from 1919 to 1931 * Dupont Brewery, a brewery in Belgium Places in the United States * Dupont, Colorado, an unincorporated community * Du Pont, Georgia, a town * Dupont, Indiana, a town * Dupont, Pointe Coupee Parish, Louisiana, an unincorporated community * Dupont, Ohio, a village * Dupont, Pennsylvania, a borough * Dupont, Tennessee, a community * DuPont, Washington, a city * Dupont, Wisconsin, a town * DuPont ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylene
Acetylene (Chemical nomenclature, systematic name: ethyne) is a chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pure form and thus is usually handled as a solution. Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities such as divinyl sulfide and phosphine.Compressed Gas Association (1995Material Safety and Data Sheet – Acetylene As an alkyne, acetylene is Saturated and unsaturated compounds, unsaturated because its two carbon atoms are Chemical bond, bonded together in a triple bond. The carbon–carbon triple bond places all four atoms in the same straight line, with CCH bond angles of 180°. The triple bond in acetylene results in a high energy content that is released when acetylene is burned. Discovery Acetylene was discovered in 1836 by Edmund Davy, who identified it as a "new carburet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
William Boon
William Robert Boon Fellow of the Royal Society, FRS Fellow of the Royal Society of Chemistry, FRSC (20 March 1911 – 28 October 1994) was a British chemist, known for developing the herbicide paraquat. Early life He was educated at St Dunstan's College and King's College London (BSc; PhD). Career ICI He developed Bipyridine compounds (4,4'-Bipyridine) in 1954 at Imperial Chemical Industries, ICI's Jealott's Hill Experimental Station (Plant Protection Limited) at Jealott's Hill (Warfield) in Berkshire (Bracknell Forest). These compounds are known as Paraquat-Gramoxone and Diquat, being released onto the market in 1958. Awards He was awarded the Mullard Award of the Royal Society in 1972 and was made a Fellow of the Royal Society in 1974. He was also a Fellow of the Royal Society of Chemistry and a King's College London#Fellowship of King's College, Fellow of King's College London. References 1911 births 1994 deaths Alumni of King's College London British chemists Fel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Imperial Chemical Industries
Imperial Chemical Industries (ICI) was a British Chemical industry, chemical company. It was, for much of its history, the largest manufacturer in Britain. Its headquarters were at Millbank in London. ICI was listed on the London Stock Exchange and was a constituent of the FT 30 and later the FTSE 100 Index, FTSE 100 indices. ICI was formed in 1926 as a result of the merger of four of Britain's leading chemical companies. From the onset, it was involved in the production of various chemicals, explosives, fertilisers, insecticides, dyestuffs, non-ferrous metals, and paints; the firm soon become involved in plastics and a variety of speciality products, including food ingredients, polymers, electronic materials, fragrances and flavourings. During the Second World War, ICI's subsidiary Nobel Enterprises, ICI Nobel produced munitions for Britain's war effort; the wider company was also involved with Britain's nuclear weapons programme codenamed Tube Alloys. Throughout the 1940s and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
