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Dimethylmagnesium
Dimethylmagnesium is an organomagnesium compound with the chemical formula . It is a white pyrophoric solid. Dimethylmagnesium is used in the synthesis of organometallic compounds. Preparation Like other dialkylmagnesium compounds, dimethylmagnesium is prepared by adding dioxane to a solution of methylmagnesium halide: : In such procedures, the dimethylmagnesium exists as the ether adduct, not the polymer. Addition of 1,4-dioxane causes precipitation of solid , a coordination polymer. This precipitation drives the Schlenk equilibrium toward . Related methods have been applied to other dialkylmagnesium compounds. Dimethylmagnesium can also be prepared by combining dimethylmercury and magnesium. Calcium metal, magnesium metal and methyl iodide reacts in diethyl ether to produce dimethylmagnesium. : Properties The structure of this compound has been determined by X-ray crystallography. The material is a polymer with the same connectivity as silicon disulfide Silicon disul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Organomagnesium Compound
Magnesium anthracenide with three thf ligands. Group 2 organometallic chemistry refers to the organic derivativess of any group 2 element. It is a subtheme to main group organometallic chemistry. By far the most common group 2 organometallic compounds are the magnesium-containing Grignard reagents which are widely used in organic chemistry. Other organometallic group 2 compounds are typically limited to academic interests. Characteristics As the group 2 elements (also referred to as the alkaline earth metals) contain two valence electrons, their chemistries have similarities group 12 organometallic compounds. Both readily assume a +2 oxidation states with higher and lower states being rare, and are less electronegative than carbon. However, as the group two elements (with the exception of beryllium) have considerably low electronegativity the resulting C-M bonds are more highly polarized and ionic-like, if not entirely ionic for the heavier barium compounds. The lighter organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Organomagnesium Compounds
Magnesium anthracenide with three thf ligands. Group 2 organometallic chemistry refers to the organic derivativess of any group 2 element. It is a subtheme to main group organometallic chemistry. By far the most common group 2 organometallic compounds are the magnesium-containing Grignard reagents which are widely used in organic chemistry. Other organometallic group 2 compounds are typically limited to academic interests. Characteristics As the group 2 elements (also referred to as the alkaline earth metals) contain two valence electrons, their chemistries have similarities group 12 organometallic compounds. Both readily assume a +2 oxidation states with higher and lower states being rare, and are less electronegative than carbon. However, as the group two elements (with the exception of beryllium) have considerably low electronegativity the resulting C-M bonds are more highly polarized and ionic-like, if not entirely ionic for the heavier barium compounds. The lighter orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dibutylmagnesium
Dibutylmagnesium is an organometallic chemical compound of magnesium. Its chemical formula is . Dibutylmagnesium is a chemical compound from the group of organomagnesium compounds. The pure substance is a waxy solid. Commercially, it is marketed as solution in heptane. Synthesis Dibutylmagnesium can be obtained by reaction of butyllithium with butylmagnesium chloride and subsequent addition of magnesium 2-ethylhexanoate. The compound can also be prepared by hydrogenation of magnesium, followed by reaction with 1-butene. It is also possible to prepare dibutylmagnesium using 2-chlorobutane, magnesium powder, and ''n''-butyllithium. Use Dibutylmagnesium is used as a convenient reagent for the preparation of organomagnesium compounds. References Terry L. Rathman: "Dibutylmagnesium". In: '' Encyclopedia of Reagents for Organic Synthesis'', 2001, doi:10.1002/047084289X.rd063 Alan W. Duff, Peter B. Hitchcock, ''et al'': "'Dibutylmagnesium', a convenient re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Methylmagnesium Chloride
Methylmagnesium chloride is an organometallic compound with the general formula . This highly flammable, colorless, and moisture sensitive compound is the simplest Grignard reagent and is commercially available, usually as a solution in tetrahydrofuran. Synthesis and reactions Relative to the more commonly encountered methylmagnesium bromide and methylmagnesium iodide, methylmagnesium chloride offers the advantages of low equivalent weight and low cost. It is prepared by the reaction of methyl chloride and magnesium in ethyl ether. left, Structure of , which is representative of the species in donor solvents. As with most Grignard reagents, methylmagnesium chloride is highly solvated by ether solvents via coordination from two oxygen atoms to give a tetrahedrally bonded magnesium center. Like methyllithium Methyllithium is the simplest organolithium reagent, with the empirical formula LiCH3. This s-block organometallic compound adopts an oligomeric structure both in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dimethylzinc
Dimethylzinc, also known as zinc methyl, DMZ, or DMZn, is a toxic organozinc compound with the chemical formula . It belongs to the large series of similar compounds such as diethylzinc. Preparation It is formed by the action of methyl iodide on zinc or zinc-sodium alloy at elevated temperatures. : Sodium assists the reaction of the zinc with the methyl iodide. Zinc iodide is formed as a byproduct. Properties Dimethylzinc is a colorless mobile volatile liquid, which has a characteristic disagreeable garlic-like odor. It is a very reactive and strong reducing agent. It is soluble in alkanes and often sold as a solution in hexanes. The triple point of dimethylzinc is ± 0.02 K. The monomeric molecule of dimethylzinc is linear at Zn center and tetragonal at C centers. Structure In the solid state the compound exists in two modifications. The tetragonal high-temperature phase shows a two-dimensional disorder, while the low-temperature phase which is monoclinic is ordered. The m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dimethylmercury
Dimethylmercury is an extremely toxic organomercury compound with the formula ( CH3)2 Hg. A volatile, flammable, dense and colorless liquid, dimethylmercury is one of the strongest known neurotoxins. Less than 0.1 mL is capable of inducing severe mercury poisoning resulting in death. Synthesis, structure, and reactions The compound was one of the earliest organometallics reported, reflecting its considerable stability. The compound was first prepared by George Buckton in 1857 by a reaction of methylmercury iodide with potassium cyanide: : 2 CH3HgI + 2 KCN → Hg(CH3)2 + 2 KI + (CN)2 + Hg Later, Edward Frankland discovered that it could be synthesized by treating sodium amalgam with methyl halides: : Hg + 2 Na + 2 CH3I → Hg(CH3)2 + 2 NaI It can also be obtained by alkylation of mercuric chloride with methyllithium: : HgCl2 + 2 LiCH3 → Hg(CH3)2 + 2 LiCl The molecule adopts a linear structure with Hg–C bond lengths of 2.083 Å. Reactivity and physical propert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Coordination Polymer
Coordination may refer to: * Coordination (linguistics), a compound grammatical construction * Coordination complex, consisting of a central atom or ion and a surrounding array of bound molecules or ions ** A chemical reaction to form a coordination complex * Coordination number or ligancy of a central atom in a molecule or crystal is the number of atoms, molecules or ions bonded to it * Language coordination, the tendency of people to mimic the language of others * Coordination (political culture), a Utopian form of political regime * Motor coordination In physiology, motor coordination is the orchestrated movement of multiple body parts as required to accomplish intended actions, like walking. This coordination is achieved by adjusting kinematic and kinetic parameters associated with each bo ..., in animal motion * '' Gleichschaltung'' the process of Nazification in Germany after 1933, often translated as "coordination" See also * Coordinate (other) * Coordin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Schlenk Equilibrium
The Schlenk equilibrium, named after its discoverer Wilhelm Schlenk, is a chemical equilibrium taking place in solutions of Grignard reagents and Hauser bases :2 RMgX MgX2 + MgR2 The process described is an equilibrium between two equivalents of an alkyl or aryl magnesium halide on the left of the equation and one equivalent each of the dialkyl or diaryl magnesium compound and magnesium halide salt on the right. Organomagnesium halides in solution also form dimers and higher oligomers, especially at high concentration. Alkyl magnesium chlorides in ether are present as dimers. The position of the equilibrium is influenced by solvent, temperature, and the nature of the various substituents. It is known that magnesium center in Grignard reagents typically coordinates two molecules of ether such as diethyl ether or tetrahydrofuran Tetrahydrofuran (THF), or oxolane, is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specificall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Pyrophoric
A substance is pyrophoric (from , , 'fire-bearing') if it ignites spontaneously in air at or below (for gases) or within 5 minutes after coming into contact with air (for liquids and solids). Examples are organolithium compounds and triethylborane. Pyrophoric materials are often water-reactive as well and will ignite when they contact water or humid air. They can be handled safely in atmospheres of argon or (with a few exceptions) nitrogen. Fire classification fire extinguishers are designated for use in fires involving metals but not pyrophoric materials in general. A related concept is hypergolicity, in which two compounds spontaneously ignite when mixed. Uses The creation of sparks from metals is based on the pyrophoricity of small metal particles, and pyrophoric alloys are made for this purpose. Practical applications include the sparking mechanisms in lighters and various toys, using ferrocerium; starting fires without matches, using a firesteel; the flintlock m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
