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Benzotriazole
Benzotriazole (BTA) is a heterocyclic compound with the chemical formula C6H5N3. Its five-membered ring contains three consecutive nitrogen atoms. This bicyclic compound may be viewed as fused rings of the aromatic compounds benzene and triazole. This white-to-light tan solid has a variety of uses, for instance, as a corrosion inhibitor for copper. Structure Benzotriazole features two fused rings. Its five-membered ring can exist in tautomers A and B, and the derivatives of both tautomers, structures C and D, can also be produced: : Various structural analyses with UV, IR and 1H-NMR spectra indicated that isomer A is predominantly present at room temperature. The bond between positions 1 and 2 and the one between positions 2 and 3 have proved to have the same bond properties. Moreover, the proton does not tightly bind to any of the nitrogen atoms, but rather migrates rapidly between positions 1 and 3. Therefore, the BTA can lose a proton to act as a weak acid (pKa = 8.2) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzotriazole Tautomers And Their Derivatives
Benzotriazole (BTA) is a heterocyclic compound with the chemical formula C6H5N3. Its five-membered ring contains three consecutive nitrogen atoms. This bicyclic compound may be viewed as fused rings of the aromatic compounds benzene and triazole. This white-to-light tan solid has a variety of uses, for instance, as a corrosion inhibitor for copper. Structure Benzotriazole features two fused rings. Its five-membered ring can exist in tautomers A and B, and the derivatives of both tautomers, structures C and D, can also be produced: : Various structural analyses with UV, IR and 1H-NMR spectra indicated that isomer A is predominantly present at room temperature. The bond between positions 1 and 2 and the one between positions 2 and 3 have proved to have the same bond properties. Moreover, the proton does not tightly bind to any of the nitrogen atoms, but rather migrates rapidly between positions 1 and 3. Therefore, the BTA can lose a proton to act as a weak acid (pKa = 8.2) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzotriazole Synthesis 01
Benzotriazole (BTA) is a heterocyclic compound with the chemical formula C6H5N3. Its five-membered ring contains three consecutive nitrogen atoms. This bicyclic compound may be viewed as fused rings of the aromatic compounds benzene and triazole. This white-to-light tan solid has a variety of uses, for instance, as a corrosion inhibitor for copper. Structure Benzotriazole features two fused rings. Its five-membered ring can exist in tautomers A and B, and the derivatives of both tautomers, structures C and D, can also be produced: : Various structural analyses with UV, IR and 1H-NMR spectra indicated that isomer A is predominantly present at room temperature. The bond between positions 1 and 2 and the one between positions 2 and 3 have proved to have the same bond properties. Moreover, the proton does not tightly bind to any of the nitrogen atoms, but rather migrates rapidly between positions 1 and 3. Therefore, the BTA can lose a proton to act as a weak acid (pKa = 8.2) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tolyltriazole
Tolyltriazole is a mixture of isomers or congeners that differ from benzotriazole by the addition of one methyl group attached somewhere on the benzene ring. "The term tolyltriazole (CAS 29385-43-1) generally efers tothe commercial mixture composed of approximately equal amounts of 4- and 5-methylbenzotriazole, with small quantities of tautomer.html"_;"title="heir_respective_7-_and_6-methyl_tautomer">heir_respective_7-_and_6-methyl_tautomers.heir respective 7- and 6-methyl tautomers">tautomer.html" ;"title="heir respective 7- and 6-methyl tautomer">heir respective 7- and 6-methyl tautomers.''o''-phenylenediamine. Isomers of methyl-''o''-phenylenediamine include 3-methyl-''o''-phenylenediamine, 4-methyl-''o''-phenylenediamine, and N-methyl-''o''-phenylenediamine (not involved here). Applications Tolyltriazole has uses similar to benzotriazole, but has better solubility in some organic solvents. Corrosion inhibitor Environmental relevance Related compounds References B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxylamine-O-sulfonic Acid
Hydroxylamine-''O''-sulfonic acid (HOSA) is the inorganic compound with molecular formula H3NO4S that is formed by the sulfonation of hydroxylamine with oleum. It is a white, water-soluble and hygroscopic, solid, commonly represented by the condensed structural formula H2NOSO3H, though it actually exists as a zwitterion and thus is more accurately represented as +H3NOSO3−. It is used as a reagent for the introduction of amine groups (–NH2), for the conversion of aldehydes into nitriles and alicyclic ketones into lactams (cyclic amides), and for the synthesis of variety of nitrogen-containing heterocycles. Preparation According to a laboratory procedure hydroxylamine-''O''-sulfonic acid can be prepared by treating hydroxylamine sulfate with fuming sulfuric acid (oleum). The industrial process is similar. :(NH3OH)2SO4 + 2SO3 → 2H2NOSO3H + H2SO4 The sulfonation of hydroxylamine can also be effected with chlorosulfonic acid by a method first published in 1925 and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biphenylene
Biphenylene is an organic compound with the formula (C6H4)2. It is a pale, yellowish solid with a hay-like odor. Despite its unusual structure, it behaves like a traditional polycyclic aromatic hydrocarbon. Bonding Biphenylene is a polycyclic hydrocarbon, composed of two benzene rings joined by two bridging bonds (as opposed to a normal ring fusion), thus forming a 6-4-6 arene system. The resulting planar structure was one of the first π-electronic hydrocarbon systems discovered to show evidence of antiaromaticity. The spectral and chemical properties show the influence of the central nring, leading to considerable interest in the system in terms of its degree of lessened aromaticity. Questions of bond alternation and ring currents have been investigated repeatedly. Both X-ray diffraction and electron diffraction studies show a considerable alternation of bond lengths, with the bridging bonds between the benzenoid rings having the unusually great length of 1.524 Å. The s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biphenylene
Biphenylene is an organic compound with the formula (C6H4)2. It is a pale, yellowish solid with a hay-like odor. Despite its unusual structure, it behaves like a traditional polycyclic aromatic hydrocarbon. Bonding Biphenylene is a polycyclic hydrocarbon, composed of two benzene rings joined by two bridging bonds (as opposed to a normal ring fusion), thus forming a 6-4-6 arene system. The resulting planar structure was one of the first π-electronic hydrocarbon systems discovered to show evidence of antiaromaticity. The spectral and chemical properties show the influence of the central nring, leading to considerable interest in the system in terms of its degree of lessened aromaticity. Questions of bond alternation and ring currents have been investigated repeatedly. Both X-ray diffraction and electron diffraction studies show a considerable alternation of bond lengths, with the bridging bonds between the benzenoid rings having the unusually great length of 1.524 Å. The s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bronze Disease
Bronze disease is an irreversible and nearly inexorable corrosion process that occurs when chlorides come into contact with bronze or other copper-bearing alloys. It can occur as both a dark green coating, or as a much lighter whitish fuzzy or furry green coating. It is not a bacterial infection, but the result of a chemical reaction with the chlorides that usually occurs due to contamination of the bronze object by saltwater or from burial in specific types of soil where chloride salts are present. If not treated, complete destruction of the affected artifact is possible. Treatment is very difficult, costly and not always effective. Transfer of chlorides from the contaminated artefact to other artefacts can spread the condition. Description Bronze disease is the chloride corrosion of cuprous (copper-based) artifacts. It was originally thought to be caused by bacteria. It is contagious in that the chlorides which cause it can spread the condition if they are brought into con ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vorozole
Vorozole (developmental code name R-76713; former tentative brand name Rizivor) is a triazole based competitive inhibitor of the aromatase enzyme. It underwent clinical testing for evaluation for use as an antineoplastic agent; however it was withdrawn from testing when no difference was detected in the duration of median survival as compared to the progestational agent megestrol acetate and research instead focused on the other third generation aromatase inhibitors anastrozole, letrozole and exemestane Exemestane, sold under the brand name Aromasin among others, is a medication used to treat breast cancer. It is a member of the class of antiestrogens known as aromatase inhibitors. Some breast cancers require estrogen to grow. Those cancers h .... References Aromatase inhibitors Benzotriazoles Chloroarenes Triazoles {{Antineoplastic-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
O-Phenylenediamine
''o''-Phenylenediamine (OPD) is an organic compound with the formula C6H4(NH2)2. This aromatic diamine is an important precursor to many heterocyclic compounds. It is isomeric with ''m''-phenylenediamine and ''p''-phenylenediamine. Preparation Commonly, 2-nitrochlorobenzene is treated with ammonia and the resulting 2-nitroaniline is then hydrogenated: :ClC6H4NO2 + 2 NH3 → H2NC6H4NO2 + NH4Cl :H2NC6H4NO2 + 3 H2 → H2NC6H4NH2 + 2 H2O In the laboratory, the reduction of the nitroaniline is effected with zinc powder in ethanol, followed by purification of the diamine as the hydrochloride salt. This compound darkens in air; impurities may be removed by treating a hot aqueous solution with sodium dithionite (reducing agent) and activated carbon, then allowing the product to cool and crystallize. Reactions and uses ''o''-Phenylenediamine condenses with ketones and aldehydes to give rise to a variety of useful products. Reactions with carboxylic acids and their derivatives affo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corrosion Inhibitor
In chemistry, a corrosion inhibitor or anti-corrosive is a chemical compound that, when added to a liquid or gas, decreases the corrosion rate of a material, typically a metal or an alloy, that comes into contact with the fluid. The effectiveness of a corrosion inhibitor depends on fluid composition, quantity of water, and flow regime. Corrosion inhibitors are common in industry, and also found in over-the-counter products, typically in spray form in combination with a lubricant and sometimes a penetrating oil. They may be added to water to prevent leaching of lead or copper from pipes. A common mechanism for inhibiting corrosion involves formation of a coating, often a passivation layer, which prevents access of the corrosive substance to the metal. Permanent treatments such as chrome plating are not generally considered inhibitors, however: corrosion inhibitors are additives to the fluids that surround the metal or related object. Types The nature of the corrosive inhibitor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alizapride
Alizapride (Litican, Plitican, Superan, Vergentan) is a dopamine antagonist with prokinetic and antiemetic effects used in the treatment of nausea and vomiting, including postoperative nausea and vomiting. It is structurally related to metoclopramide and other benzamide Benzamide is a organic compound with the chemical formula of C6H5C(O)NH2. It is the simplest amide derivative of benzoic acid. In powdered form, it appears as a white solid, while in crystalline form, it appears as colourless crystals. It is slig ...s. References Antiemetics Dopamine antagonists Motility stimulants Salicylamide ethers Benzotriazoles Pyrrolidines Allyl compounds {{gastrointestinal-drug-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Derivative (chemistry)
In chemistry, a derivative is a compound that is derived from a similar compound by a chemical reaction. In the past, derivative also meant a compound that ''can be imagined to'' arise from another compound, if one atom or group of atoms is replaced with another atom or group of atoms, but modern chemical language now uses the term structural analog for this meaning, thus eliminating ambiguity. The term "structural analogue" is common in organic chemistry. In biochemistry, the word is used for compounds that at least theoretically can be formed from the precursor compound. Chemical derivatives may be used to facilitate analysis. For example, melting point (MP) analysis can assist in identification of many organic compounds. A crystalline derivative may be prepared, such as a semicarbazone or 2,4-dinitrophenylhydrazone (derived from aldehydes or ketones), as a simple way of verifying the identity of the original compound, assuming that a table of derivative MP values is avail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
