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Manganese(III) Acetate
Manganese(III) acetate describes a family of materials with the approximate formula Mn(O2CCH3)3. These materials are brown solids that are soluble in acetic acid and water. They are used in organic synthesis as oxidizing agents. Structure Although manganese(III) triacetate has not been reported, salts of basic manganese(III) acetate are well characterized. Basic manganese acetate adopts the structure reminiscent of those of basic chromium acetate and basic iron acetate. The formula is n3O(O2CCH3)6Ln where L is a ligand and X is an anion. The salt n3O(O2CCH3)62CCH3.HO2CCH3 has been confirmed by X-ray crystallography. Preparation It is usually used as the dihydrate, although the anhydrous form is also used in some situations. The dihydrate is prepared by combining potassium permanganate and manganese(II) acetate in acetic acid. Addition of acetic anhydride to the reaction produces the anhydrous form. It is also synthesized by electrochemical method starting from Mn(OAc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one of the most important branches of organic chemistry. There are several main areas of research within the general area of organic synthesis: ''total synthesis'', ''semisynthesis'', and ''methodology''. Total synthesis A total synthesis is the complete chemical synthesis of complex organic molecules from simple, commercially available petrochemical or natural precursors. Total synthesis may be accomplished either via a linear or convergent approach. In a ''linear'' synthesis—often adequate for simple structures—several steps are performed one after another until the molecule is complete; the chemical compounds made in each step are called synthetic intermediates. Most often, each step in a synthesis refers to a separate rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Encyclopedia Of Reagents For Organic Synthesis
The ''Encyclopedia of Reagents for Organic Synthesis'' is published in print and online by John Wiley & Sons Ltd. The online version is also known as e-EROS. The encyclopedia contains a description of the use of reagents used in organic chemistry. The eight-volume print version includes 3500 alphabetically arranged articles and the online version is regularly updated to include new reagents and catalyst Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...s. References External links *Print version Encyclopedias of science Chemistry books {{encyclopedia-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese(III) Compounds
Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy uses, particularly in stainless steels. It improves strength, workability, and resistance to wear. Manganese oxide is used as an oxidising agent; as a rubber additive; and in glass making, fertilisers, and ceramics. Manganese sulfate can be used as a fungicide. Manganese is also an essential human dietary element, important in macronutrient metabolism, bone formation, and free radical defense systems. It is a critical component in dozens of proteins and enzymes. It is found mostly in the bones, but also the liver, kidneys, and brain. In the human brain, the manganese is bound to manganese metalloproteins, most notably glutamine synthetase in astrocytes. Manganese was first isolated in 1774. It is familiar in the laboratory in the form of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetates
An acetate is a salt formed by the combination of acetic acid with a base (e.g. alkaline, earthy, metallic, nonmetallic or radical base). "Acetate" also describes the conjugate base or ion (specifically, the negatively charged ion called an anion) typically found in aqueous solution and written with the chemical formula . The neutral molecules formed by the combination of the acetate ion and a ''positive'' ion (called a cation) are also commonly called "acetates" (hence, ''acetate of lead'', ''acetate of aluminum'', etc.). The simplest of these is hydrogen acetate (called acetic acid) with corresponding salts, esters, and the polyatomic anion , or . Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In nature, acetate is the most common building block for biosynthesis. Nomenclature and common formula When part of a salt, the formula of the acetate ion is wr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc Acetate
Zinc acetate is a salt with the formula Zn(CH3CO2)2, which commonly occurs as the dihydrate Zn(CH3CO2)2·2H2O. Both the hydrate and the anhydrous forms are colorless solids that are used as dietary supplements. When used as a food additive, it has the E number E650. Uses Zinc acetate is a component of some medicines, e.g., lozenges for treating the common cold. Zinc acetate can also be used as a dietary supplement. As an oral daily supplement it is used to inhibit the body's absorption of copper as part of the treatment for Wilson's disease. Zinc acetate is also sold as an astringent in the form of an ointment, a topical lotion, or combined with an antibiotic such as erythromycin for the topical treatment of acne. It is commonly sold as a topical anti-itch ointment. Zinc acetate is used as the catalyst for the industrial production of vinyl acetate from acetylene: Approximately 1/3 of the worlds production uses this route, which because it is environmentally messy, is mainly p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron(III) Acetate
Ferric acetate is the acetate salt of the coordination complex e3O(OAc)6(H2O)3sup>+ (OAc− is CH3CO2−). Commonly the salt is known as "basic iron acetate". The formation of the red-brown complex was once used as a test for ferric ions. Structure and synthesis Basic iron acetate forms on treating aqueous solutions of iron(III) sources with acetate salts. A typical precursor is freshly precipitated iron oxide/hydroxide, which is halide-free. Early work showed that the cation is trinuclear. The Fe centres are equivalent, each being octahedral, being bound to six oxygen ligands, including a triply bridging oxide at the center of the equilateral triangle. The compound was an early example of a molecular complex of iron that features an oxide ligand. The cation has idealized D3h symmetry. Reactions The terminal aqua ligands on the trimetallic framework can be substituted with other ligands, such as pyridine and dimethylformamide. Many different salts are known by exchanging ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromium(III) Acetate
Chromium(III) acetate, commonly known as basic chromium acetate, describes a family of salts where the cation has the formula r3O(O2CCH3)6(OH2)3sup>+. The trichromium cation is encountered with a variety of anions, such as chloride and nitrate. Data in the table above are for the chloride hexahydrate, r3O(O2CCH3)6(OH2)3l(H2O)6. Salts of basic chromium acetate has long attracted interest because of its distinctive structure, which features octahedral Cr(III) centers, a triply bridging oxo ligand, six acetate ligands, and three aquo ligands. The same structure is shared with basic iron acetate and basic manganese acetate. Little evidence exists for a simple chromium(III) acetate, i.e. lacking the oxo ligand. Chromium(III) acetate is a blue/grey-green powder, which is soluble in water. It is still prepared according to the original procedure from 1909. See also * Chromium acetate hydroxide * Chromium(II) acetate Chromium(II) acetate hydrate, also known as chromous acetate, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese(II) Acetate
Manganese(II) acetate are chemical compounds with the formula where n = 0, 2, 4. These materials are white or pale pink solids. Some of these compounds are used as a catalyst and as fertilizer. Preparation Manganese(II) acetate can be formed by treating either manganese(II,III) oxide or manganese(II) carbonate with acetic acid: : : Structure The anhydrous material and dihydrate are coordination polymers. The dihydrate has been characterized by X-ray crystallography. Each Mn(II) center is surrounded by six oxygen centers provided by aquo ligand In chemistry, metal aquo complexes are coordination compounds containing metal ions with only water as a ligand. These complexes are the predominant species in aqueous solutions of many metal salts, such as metal nitrates, sulfates, and perch ...s and acetates. References {{DEFAULTSORT:Manganese(II) Acetate Manganese(II) compounds Acetates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese(III) Chloride
Manganese(III) chloride is the hypothetical inorganic compound with the formula MnCl3. The existence of this Binary phase, binary halide has not been demonstrated. Nonetheless, many derivatives of MnCl3 are known, such as MnCl3(THF)3 and the bench-stable Bis(triphenylphosphineoxide) manganese(III) chloride, MnCl3(OPPh3)2. Contrasting with the elusive nature of MnCl3, trichlorides of the adjacent metals on the periodic table—iron(III) chloride, chromium(III) chloride, and Technetium trichloride, technetium(III) chloride—are all isolable compounds. History of MnCl3 and its adducts MnCl3 was claimed to be a dark solid and produced by the reaction of "anhydrous manganese(III) acetate" and liquid hydrogen chloride at −100 °C and decomposes above -40 °C. Other claims involved reaction of manganese(III) oxide, manganese(III) oxide-hydroxide, and basic manganese acetate with hydrochloric acid. Given recent investigations however, such claims have been disproved or c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manganese-mediated Coupling Reactions
Manganese-mediated coupling reactions are radical coupling reactions between enolizable carbonyl compounds and unsaturated compounds initiated by a manganese(III) salt, typically manganese(III) acetate. Copper(II) acetate is sometimes used as a co-oxidant to assist in the oxidation of intermediate radicals to carbocations. Manganese(III) acetate is effective for the one-electron oxidation of enolizable carbonyl compounds to α-oxoalkyl or α,α'-dioxoalkyl radicals. Radicals generated in this manner may then undergo inter- or intramolecular addition to carbon-carbon multiple bonds. Pathways available to the adduct radical include further oxidation to a carbocation (and subsequent β-elimination or trapping with a nucleophile) and hydrogen abstraction to generate a saturated carbonyl compound containing a new carbon-carbon bond. Copper(II) acetate is sometimes needed to facilitate the oxidation of adduct radicals to carbocations. Yields of these reactions are generally moderate, parti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetoxy Group
In organic chemistry, the acetoxy group (abbr. AcO or OAc; IUPAC name: acetyloxy), is a functional group with the formula and the structure . As the ''-oxy'' suffix implies, it differs from the acetyl group () by the presence of an additional oxygen atom. The name acetoxy is the short form of ''acetyl-oxy''. Functionality An acetoxy group may be used as a protection for an alcohol functionality in a synthetic route although the protecting group itself is called an acetyl group. Alcohol protection There are several options of introducing an acetoxy functionality in a molecule from an alcohol (in effect protecting the alcohol by acetylation): * Acetyl halide, such as acetyl chloride in the presence of a base like triethylamine * Activated ester form of acetic acid, such as a N-hydroxysuccinimide ester, although this is not advisable due to higher costs and difficulties. * Acetic anhydride in the presence of base with a catalyst such as pyridine with a bit of DMAP added. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
