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Diethylaluminum Cyanide
Diethylaluminium cyanide ("Nagata's reagent") is the organoaluminium compound with formula . This colorless compound is usually handled as a solution in toluene. It is a reagent for the hydrocyanation of α,β-unsaturated ketones. Synthesis Diethylaluminium cyanide was originally generated by treatment of triethylaluminium with a slight excess of hydrogen cyanide. The product is typically stored in ampoules because it is highly toxic. It dissolves in toluene, benzene, hexane and isopropyl ether. It undergoes hydrolysis readily and is not compatible with protic solvents. : Structure Diethylaluminium cyanide has not been examined by X-ray crystallography, although other diorganoaluminium cyanides have been. Diorganylaluminium cyanides have the general formula , and they exist as cyclic trimer (chemistry), trimers (''n'' = 3) or tetramers (''n'' = 4). In these oligomers, one finds AlCN---Al linkages. One compound similar to diethylaluminium cyanide is bis[di(trimethylsilyl)methyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organoaluminium Compound
Organoaluminium chemistry is the study of compounds containing bonds between carbon and aluminium. It is one of the major themes within organometallic chemistry. Illustrative organoaluminium compounds are the dimer trimethylaluminium, the monomer triisobutylaluminium, and the titanium-aluminium compound called Tebbe's reagent. The behavior of organoaluminium compounds can be understood in terms of the polarity of the C−Al bond and the high Lewis acidity of the three-coordinated species. Industrially, these compounds are mainly used for the production of polyolefins. History The first organoaluminium compound (C2H5)3Al2I3 was discovered in 1859. Organoaluminium compounds were, however, little known until the 1950s when Karl Ziegler and colleagues discovered the direct synthesis of trialkylaluminium compounds and applied these compounds to catalytic olefin polymerization. This line of research ultimately resulted in the Nobel Prize to Ziegler. Structure and bonding Aluminium( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution reaction, substitution, elimination reaction, elimination, and solvation reactions in which water is the nucleophile. Biological hydrolysis is the cleavage of Biomolecule, biomolecules where a water molecule is consumed to effect the separation of a larger molecule into component parts. When a carbohydrate is broken into its component sugar molecules by hydrolysis (e.g., sucrose being broken down into glucose and fructose), this is recognized as saccharification. Hydrolysis reactions can be the reverse of a condensation reaction in which two molecules join into a larger one and eject a water molecule. Thus hydrolysis adds water to break down, whereas condensation builds up by removing water. Types Usually hydrolysis is a chemical process in which a molecule of water is added to a substance. Sometimes this addition causes both the su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanides
In chemistry, cyanide () is an inorganic chemical compound that contains a functional group. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom. Ionic cyanides contain the cyanide anion . This anion is extremely poisonous. Soluble cyanide salts such as sodium cyanide (NaCN), potassium cyanide (KCN) and tetraethylammonium cyanide () are highly toxic. Covalent cyanides contain the group, and are usually called nitriles if the group is linked by a single covalent bond to carbon atom. For example, in acetonitrile , the cyanide group is bonded to methyl . In tetracyanomethane , four cyano groups are bonded to carbon. Although nitriles generally do not release cyanide ions, the cyanohydrins do and are thus toxic. The cyano group may be covalently bonded to atoms different than carbon, e.g., in cyanogen azide , phosphorus tricyanide and trimethylsilyl cyanide . Hydrogen cyanide, or , is a highly volatile toxic liquid that is produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basicity
In chemistry, there are three definitions in common use of the word "base": ''Arrhenius bases'', ''Brønsted bases'', and ''Lewis bases''. All definitions agree that bases are substances that react with acids, as originally proposed by Guillaume-François Rouelle, G.-F. Rouelle in the mid-18th century. In 1884, Svante Arrhenius proposed that a base is a substance which dissociates in aqueous solution to form hydroxide ions OH−. These ions can react with Hydron (chemistry), hydrogen ions (H+ according to Arrhenius) from the dissociation of acids to form water in an acid–base reaction. A base was therefore a metal hydroxide such as NaOH or Calcium hydroxide, Ca(OH)2. Such aqueous hydroxide solutions were also described by certain characteristic properties. They are slippery to the touch, can taste Taste#Bitterness, bitter and change the color of pH indicators (e.g., turn red litmus paper blue). In water, by altering the self-ionization of water, autoionization Chemical equi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zeitschrift Für Anorganische Und Allgemeine Chemie
The ''Zeitschrift für anorganische und allgemeine Chemie'' (''Journal of Inorganic and General Chemistry'') is a semimonthly peer-reviewed scientific journal covering inorganic chemistry, published by Wiley-VCH. The editors-in-chief are Thomas F. Fässler, Christian Limberg, Guodong Qian, and David Scheschkewitz. Originally the journal was published in German, but nowadays it is completely in English. Abstracting and indexing The journal is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2022 impact factor of 1.4. History In 1892, Gerhard Krüss (Ludwig Maximilian University of Munich), established the journal under the name ''Zeitschrift für Anorganische Chemie''. Krüss died three years later, and was succeeded by Richard Lorenz and Walther Nernst Walther Hermann Nernst (; 25 June 1864 – 18 November 1941) was a German physical chemist known for his work in thermodynamics, physical chemistry, electrochemistry, and solid-sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trimer (chemistry)
In chemistry, a trimer (; ) is a molecule or polyatomic anion formed by combination or association of three molecules or ions of the same substance. In technical jargon, a trimer is a kind of oligomer derived from three identical Precursor (chemistry), precursors often in competition with polymerization. Examples Alkyne trimerization In 1866, Marcellin Berthelot reported the first example of cyclotrimerization, the conversion of acetylene to benzene. This process was commercialized: : Nitrile trimerization Symmetrical 1,3,5-triazines are prepared by trimerization of certain nitriles such as cyanogen chloride. Cyanogen chloride and cyanogen bromide each trimerize at elevated temperatures over a carbon catalyst. The chloride gives cyanuric chloride: : The bromide has an extended shelflife when refrigerated. Like the chloride, it undergoes ab exothermic trimerization to form cyanuric bromide. This reaction is catalyzed by traces of bromine, metal salts, acids and bases. For th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
X-ray Crystallography
X-ray crystallography is the experimental science of determining the atomic and molecular structure of a crystal, in which the crystalline structure causes a beam of incident X-rays to Diffraction, diffract in specific directions. By measuring the angles and intensities of the X-ray diffraction, a crystallography, crystallographer can produce a three-dimensional picture of the density of electrons within the crystal and the positions of the atoms, as well as their chemical bonds, crystallographic disorder, and other information. X-ray crystallography has been fundamental in the development of many scientific fields. In its first decades of use, this method determined the size of atoms, the lengths and types of chemical bonds, and the atomic-scale differences between various materials, especially minerals and alloys. The method has also revealed the structure and function of many biological molecules, including vitamins, drugs, proteins and nucleic acids such as DNA. X-ray crystall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protic Solvents
In chemistry, a protic solvent is a solvent that has a hydrogen atom bound to an oxygen (as in a hydroxyl group ), a nitrogen (as in an amine group or ), or fluoride (as in hydrogen fluoride). In general terms, any solvent that contains a labile is called a protic solvent. The molecules of such solvents readily donate protons () to solutes, often via hydrogen bonding. Water is the most common protic solvent. Conversely, polar aprotic solvents cannot donate protons but still have the ability to dissolve many salts. Methods for purification of common solvents are available See also * Autoprotolysis In chemistry, autoprotolysis is a molecular autoionization, a chemical reaction in which a proton is transferred between two identical molecules, one of which acts as a Brønsted acid, releasing a proton that is accepted by the other molecule, wh ... References {{Chemical solutions Solvents ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isopropyl Ether
Diisopropyl ether is a secondary ether that is used as a solvent. It is a colorless liquid that is slightly soluble in water, but miscible with organic solvents. It is used as an extractant and an oxygenate gasoline additive. It is obtained industrially as a byproduct in the production of isopropanol by hydration reaction, hydration of propylene. Diisopropyl ether is sometimes represented by the abbreviation DIPE. Uses Whereas at 20 °C, diethyl ether will dissolve 1% by weight water, diisopropyl ether dissolves 0.88%. Diisopropyl ether is used as a specialized solvent to remove or extract polar organic compounds from aqueous solutions, e.g. phenols, ethanol, acetic acid. It has also been used as an antiknock agent. In the laboratory, diisopropyl ether is useful for Recrystallization (chemistry), recrystallizations because it has a wide liquid range. Diisopropyl ether is used for converting bromoboranes, which are thermally labile, into isopropoxy derivatives. Safety Diisoprop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
