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Transition Metal Nitroso Complexes
Structure of the dye Naphthol Green B, which features of nitroso ligand bound to Fe(III). Transition metal nitroso complexes are coordination complexes containing one or more organonitroso ligands (RNO). Structure and bonding Organic nitroso compounds bind to metals in several ways, but most commonly as monodentate N-bonded ligands. Also known are O-bonded, η2-N,O-bonded. Dimers of organic nitroso compounds also bind in a κ2--O,O bidentate manner. Illustrative are , where a pair nitrosobenzenes are monodentate, and where two nitrosobenzenes bridge. Chelating nitroso ligands : Arylnitroso compounds with a flanking hydroxy group are a well-developed, e.g. 1-nitroso-2-naphthol. They are precursors to anionic N,O chelating ligands. Chelating dinitrosoarenes are uncommon but have been investigated. Synthesis Organic nitroso complexes can be prepared from preformed organic nitroso precursors. These precursors usually exist as N-N bonded dimers, but the dimer dissociates read ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methemoglobinemia
Methemoglobinemia, or methaemoglobinaemia, is a condition of elevated methemoglobin in the blood. Symptoms may include headache, dizziness, shortness of breath, nausea, poor muscle coordination, and blue-colored skin (cyanosis). Complications may include seizures and heart arrhythmias. Methemoglobinemia can be due to certain medications, chemicals, or food or it can be inherited. Substances involved may include benzocaine, nitrites, or dapsone. The underlying mechanism involves some of the iron in hemoglobin being converted from the ferrous [Fe2+] to the ferric [Fe3+] form. The diagnosis is often suspected based on symptoms and a Hypoxia (medical), low blood oxygen that does not improve with oxygen therapy. Diagnosis is confirmed by a blood gas. Treatment is generally with oxygen therapy and methylene blue. Other treatments may include vitamin C, exchange transfusion, and hyperbaric oxygen therapy. Outcomes are generally good with treatment. Methemoglobinemia is relatively unc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Complexes
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the periodic table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Millon's Reagent
Millon's reagent is an analytical reagent used to detect the presence of soluble proteins. A few drops of the reagent are added to the test solution, which is then heated gently. A reddish-brown coloration or precipitate indicates the presence of tyrosine residue which occur in nearly all proteins. The test was developed by the French chemist Auguste Nicolas Eugene Millon. The structure of the metal complex is usually misrepresented. It is an nitroso complex, with M-N bonds. The reagent is made by dissolving metallic mercury in nitric acid and diluting with water, forming mercuric nitrate (Hg O3sub>2). In the test, the phenol group in the side chain of tyrosine gets nitrated, and that product then complexes with Hg(I) or Hg(II) ions to give a red colored precipitate. Millon's test is not specific for proteins; it also gives a positive test for other compounds containing the phenol functional group In organic chemistry, a functional group is any substituent or moiety (chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cupferron
Cupferron is jargon for the ammonium salt of the conjugate base derived from ''N''-nitroso-''N''-phenylhydroxylamine. This conjugate base is abbreviated as CU−. It once was a common reagent for the complexation of metal ions, being of interest in the area of qualitative inorganic analysis. Its formula is NH4 6H5N(O)NO The anion binds to metal cations through the two oxygen atoms, forming five-membered chelate Chelation () is a type of bonding of ions and their molecules to metal ions. It involves the formation or presence of two or more separate coordinate bonds between a polydentate (multiple bonded) ligand and a single central metal atom. These l ... rings. Synthesis and complexes Cupferron is prepared from phenylhydroxylamine and an NO+ source: ::C6H5NHOH + C4H9ONO + NH3 → NH4 6H5N(O)NO+ C4H9OH Being a bidentate mono-anionic ligand, CU− forms complexes analogous to those produced with acetylacetonate. Illustrative complexes include Cu(CU)2, Fe(CU)3, and Zr(CU)4. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aniline
Aniline (From , meaning ' indigo shrub', and ''-ine'' indicating a derived substance) is an organic compound with the formula . Consisting of a phenyl group () attached to an amino group (), aniline is the simplest aromatic amine. It is an industrially significant commodity chemical, as well as a versatile starting material for fine chemical synthesis. Its main use is in the manufacture of precursors to polyurethane, dyes, and other industrial chemicals. Like most volatile amines, it has the odor of rotten fish. It ignites readily, burning with a smoky flame characteristic of aromatic compounds. It is toxic to humans. Relative to benzene, aniline is "electron-rich". It thus participates more rapidly in electrophilic aromatic substitution reactions. Likewise, it is also prone to oxidation: while freshly purified aniline is an almost colorless oil, exposure to air results in gradual darkening to yellow or red, due to the formation of strongly colored, oxidized impurities. Ani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methemoglobin
Methemoglobin (British: methaemoglobin, shortened MetHb) (pronounced "met-hemoglobin") is a hemoglobin ''in the form of metalloprotein'', in which the iron in the heme group is in the Fe3+ (ferric) state, not the Fe2+ (ferrous) of normal hemoglobin. Sometimes, it is also referred to as ferrihemoglobin. Methemoglobin cannot bind oxygen, which means it cannot carry oxygen to tissues. It is bluish chocolate-brown in color. In human blood a trace amount of methemoglobin is normally produced spontaneously, but when present in excess the blood becomes abnormally dark bluish brown. The NADH-dependent enzyme methemoglobin reductase (diaphorase, a type of diaphorase) is responsible for converting methemoglobin back to hemoglobin. Normally one to two percent of a person's hemoglobin is methemoglobin; a higher percentage than this can be genetic or caused by exposure to various chemicals and depending on the level can cause health problems known as methemoglobinemia. A higher level of methemog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemoglobin
Hemoglobin (haemoglobin, Hb or Hgb) is a protein containing iron that facilitates the transportation of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the sole exception of the fish family Channichthyidae. Hemoglobin in the blood carries oxygen from the respiratory organs (lungs or gills) to the other tissues of the body, where it releases the oxygen to enable aerobic respiration which powers an animal's metabolism. A healthy human has 12to 20grams of hemoglobin in every 100mL of blood. Hemoglobin is a metalloprotein, a chromoprotein, and a globulin. In mammals, hemoglobin makes up about 96% of a red blood cell's dry matter, dry weight (excluding water), and around 35% of the total weight (including water). Hemoglobin has an oxygen-binding capacity of 1.34mL of O2 per gram, which increases the total blood oxygen capacity seventy-fold compared to dissolved oxygen in blood plasma alone. The mammalian hemoglobin molecule can bind and transport up to four ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CSD CIF FAVGUE
CSD may refer to: Finance * Central securities depository * Confederate States Dollar * Serbian dinar, by previous ISO 4217 code Organizations Education * California School for the Deaf (other), several institutions * Canyons School District, in Utah, US * Cheltenham School District, in Pennsylvania, US * Christina School District, in Delaware, US * Cleveland School District, in Mississippi, US * Cordova School District, in Alaska, US Other organizations * Canteen Stores Department (India), a chain of stores operated by the Indian Ministry of Defence at military bases * CSD Pakistan (Canteen Stores Department), a chain of stores operated by the Pakistani Ministry of Defence * Chartered Society of Designers, a British learned society for various kinds of design work * Commission on Sustainable Development (1992–2013), a former UN agency * Communication Service for the Deaf, an American non-profit company providing ASL services * Congress of Democratic Trade Unions (Que ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Complex
A coordination complex is a chemical compound consisting of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of chemical bond, bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing chemical compound, compounds, especially those that include transition metals (elements like titanium that belong to the periodic table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A Ligand#Polydentate and polyhapto ligand motifs and nomenclature, polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenylhydroxylamine
''N''-Phenylhydroxylamine is the organic compound with the formula C6H5NHOH. It is an intermediate in the redox-related pair C6H5NH2 and C6H5NO. ''N''-Phenylhydroxylamine should not be confused with its isomer α-phenylhydroxylamine or ''O''-phenylhydroxylamine. Preparation This compound can be prepared by the reduction of nitrobenzene with zinc in the presence of NH4Cl. Alternatively, it can be prepared by transfer hydrogenation of nitrobenzene using hydrazine as an H2 source over a rhodium catalyst. Reactions Phenylhydroxylamine is unstable to heating, and in the presence of strong acids easily rearranges to 4-aminophenol via the Bamberger rearrangement. Oxidation of phenylhydroxylamine with dichromate gives nitrosobenzene. Like other hydroxylamines it will react with aldehydes to form nitrones, illustrative is the condensation with benzaldehyde to form diphenylnitrone, a well-known 1,3-dipolar compound: :C6H5NHOH + C6H5CHO → C6H5N(O)=CHC6H5 + H2O Phenylhydroxyla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrobenzene
Nitrobenzene is an aromatic nitro compound and the simplest of the nitrobenzenes, with the chemical formula C6H5 NO2. It is a water-insoluble pale yellow oil with an almond-like odor. It freezes to give greenish-yellow crystals. It is produced on a large scale from benzene as a precursor to aniline. In the laboratory, it is occasionally used as a solvent, especially for electrophilic reagents. As confirmed by X-ray crystallography, nitrobenzene is a planar molecule. Production Nitrobenzene is prepared by nitration of benzene with a mixture of concentrated sulfuric acid, water, and nitric acid. This mixture is sometimes called "mixed acid." The production of nitrobenzene is one of the most dangerous processes conducted in the chemical industry because of the exothermicity of the reaction (Δ''H'' = −117 kJ/mol). World capacity for nitrobenzene in 1985 was about 1,700,000 tonnes. The nitration process involves formation of the nitronium ion (NO2+), followed by an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
