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2,3-Butanediamine
2,3-Butanediamine are organic compounds with the formula CH3CH(NH2)CH(NH2)CH3. Three stereoisomers exist, meso and a pair of enantiomers. These diamines form complexes with transition metals. Synthesis 2,3-Butanediamines can be prepared by hydrolyzing 2-ethoxy-4,5-dihydro-4,5-dimethylimidazole with barium hydroxide. Alternative, it is produced by reduction of dimethylglyoxime with lithium aluminium hydride. The meso and the d,l diastereomers can be separated by fractional crystallization of the hydrochlorides. The enantiomers have been resolved using tartrate salts. Reactions In coordination chemistry, 2,3-butanediamine (abbreviated bn) has illuminates aspects of the stereochemistry. The structure of o(meso-2,3-butanediamine)2CO3sup>+ confirms the presence of the rarely observed axial methyl groups on each of the diamine-cobalt rings. Related compounds *1,2-Diaminopropane 1,2-Diaminopropane (propane-1,2-diamine) is organic compound with the formula CHCH(NH)CHNH. A col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C4H12N2
The molecular formula C4H12N2 (molar mass: 88.15 g/mol) may refer to: * Dimethylethylenediamines ** 1,1-Dimethylethylenediamine ** 1,2-Dimethylethylenediamine * 2,3-Butanediamine * Putrescine * Tetramethylhydrazine {{MolFormIndex Molecular formulas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimethylglyoxime
Dimethylglyoxime is a chemical compound described by the formula CH3C(NOH)C(NOH)CH3. Its abbreviation is dmgH2 for neutral form, and dmgH− for anionic form, where H stands for hydrogen. This colourless solid is the dioxime derivative of the diketone butane-2,3-dione (also known as diacetyl). DmgH2 is used in the analysis of palladium or nickel. Its coordination complexes are of theoretical interest as models for enzymes and as catalysts. Many related ligands can be prepared from other diketones, e.g. benzil. Preparation and reactions Dimethylglyoxime can be prepared from butanone first by reaction with ethyl nitrite to give biacetyl monoxime. The second oxime is installed using sodium hydroxylamine monosulfonate: 2,3-Butanediamine is produced by reduction of dimethylglyoxime with lithium aluminium hydride. Complexes Dimethylglyoxime forms complexes with metals including nickel, palladium and cobalt. These complexes are used to separate those cations from solutions of met ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-Diaminopropane
1,2-Diaminopropane (propane-1,2-diamine) is organic compound with the formula CHCH(NH)CHNH. A colorless liquid, it is the simplest chiral diamine. Preparation Industrially, this compound is synthesized by the ammonolysis of 1,2-dichloropropane: :CHCHClCHCl + 4 NH → CHCH(NH)CHNH + 2 NHCl This preparation allows for the use of waste chloro-organic compounds to form useful amines using inexpensive and readily available ammonia. The racemic mixture of this chiral compound may be separated into enantiomers by conversion into the diastereomeric tartaric acid ammonium salt. After purification of the diastereomer, the diamine can be regenerated by treatment of the ammonium salt with sodium hydroxide. Alternate reagents for chiral resolution include N-p-toluenesulfonylaspartic acid, N-benzenesulfonylaspartic acid, or N-benzoylglutamic acid. Uses 1,2-Diaminopropane is used in the synthesis of ''N'',''N''-disalicylidene-1,2-propanediamine, a salen-type ligand, usually abbreviated as s ... [...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] |
Meso Isomer
A meso compound or meso isomer is an optically inactive isomer in a set of stereoisomers, at least two of which are optically active. This means that despite containing two or more stereocenters, the molecule is not chiral. A meso compound is superposable on its mirror image (not to be confused with superimposable, as any two objects can be superimposed over one another regardless of whether they are the same). Two objects can be superposed if all aspects of the objects coincide and it does not produce a "(+)" or "(-)" reading when analyzed with a polarimeter. The name is derived from the Greek ''mésos'' meaning “middle”. For example, tartaric acid can exist as any of three stereoisomers depicted below in a Fischer projection. Of the four colored pictures at the top of the diagram, the first two represent the meso compound (the 2'' R'',3'' S'' and 2'' S'',3'' R'' isomers are equivalent), followed by the optically active pair of levotartaric acid (L-(''R,R'')-(+)-tartaric aci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barium Hydroxide
Barium hydroxide is a chemical compound with the chemical formula Ba(OH)2. The monohydrate (''x'' = 1), known as baryta or baryta-water, is one of the principal compounds of barium. This white granular monohydrate is the usual commercial form. Preparation and structure Barium hydroxide can be prepared by dissolving barium oxide (BaO) in water: :BaO + H2O → Ba(OH)2 It crystallises as the octahydrate, which converts to the monohydrate upon heating in air. At 100 °C in a vacuum, the monohydrate will yield BaO and water. The monohydrate adopts a layered structure (see picture above). The Ba2+ centers adopt a square antiprismatic geometry. Each Ba2+ center is bound by two water ligands and six hydroxide ligands, which are respectively doubly and triply bridging to neighboring Ba2+ centre sites. In the octahydrate, the individual Ba2+ centers are again eight coordinate but do not share ligands. Uses Industrially, barium hydroxide is used as the precursor to other bar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lithium Aluminium Hydride
Lithium aluminium hydride, commonly abbreviated to LAH, is an inorganic compound with the chemical formula or . It is a white solid, discovered by Finholt, Bond and Schlesinger in 1947. This compound is used as a reducing agent in organic synthesis, especially for the reduction of esters, carboxylic acids, and amides. The solid is dangerously reactive toward water, releasing gaseous hydrogen (H2). Some related derivatives have been discussed for hydrogen storage. Properties, structure, preparation LAH is a colourless solid but commercial samples are usually gray due to contamination. This material can be purified by recrystallization from diethyl ether. Large-scale purifications employ a Soxhlet extractor. Commonly, the impure gray material is used in synthesis, since the impurities are innocuous and can be easily separated from the organic products. The pure powdered material is pyrophoric, but not its large crystals. Some commercial materials contain mineral oil to inhibit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Resolution
Optical resolution describes the ability of an imaging system to resolve detail, in the object that is being imaged. An imaging system may have many individual components, including one or more lenses, and/or recording and display components. Each of these contributes (given suitable design, and adequate alignment) to the optical resolution of the system; the environment in which the imaging is done often is a further important factor. Lateral resolution Resolution depends on the distance between two distinguishable radiating points. The sections below describe the theoretical estimates of resolution, but the real values may differ. The results below are based on mathematical models of Airy discs, which assumes an adequate level of contrast. In low-contrast systems, the resolution may be much lower than predicted by the theory outlined below. Real optical systems are complex, and practical difficulties often increase the distance between distinguishable point sources. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tartrate
A tartrate is a salt or ester of the organic compound tartaric acid, a dicarboxylic acid. The formula of the tartrate dianion is O−OC-CH(OH)-CH(OH)-COO− or C4H4O62−. The main forms of tartrates used commercially are pure crystalline tartaric acid used as an acidulant in non-alcoholic drinks and foods, cream of tartar used in baking, and Rochelle salt, commonly used in electroplating solutions. As food additives As food additives, tartrates are used as antioxidants, acidity regulators, and emulsifiers. Examples include *sodium tartrates ( E335) **monosodium tartrate ** sodium tartrate ** sodium ammonium tartrate the compound through which Louis Pasteur discovered chirality *potassium tartrates ( E336) ** potassium bitartrate (monopotassium tartrate, cream of tartar) ** potassium tartrate * potassium sodium tartrate ( E337) * calcium tartrate ( E354, used as emulsifier) * stearyl tartrate ( E483, used as emulsifier) In wine In wine, tartrates are the harmless cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stereochemistry
Stereochemistry, a subdiscipline of chemistry, studies the spatial arrangement of atoms that form the structure of molecules and their manipulation. The study of stereochemistry focuses on the relationships between stereoisomers, which are defined as having the same molecular formula and sequence of bonded atoms (constitution) but differing in the geometric positioning of the atoms in space. For this reason, it is also known as Three-dimensional space, 3D chemistry—the prefix "stereo-" means "three-dimensionality". Stereochemistry applies to all kinds of compounds and ions, Organic chemistry, organic and Inorganic chemistry, inorganic species alike. Stereochemistry affects Biochemistry, biological, Physical chemistry, physical, and supramolecular chemistry. Stereochemistry reactivity (chemistry), reactivity of the molecules in question (dynamic stereochemistry). History In 1815, Jean-Baptiste Biot's observation of optical activity marked the beginning of organic stereochemistr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
