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Tetrabutylammonium
Tetrabutylammonium is a quaternary ammonium cation with the formula (C4H9)4sup>+. It is used in the research laboratory to prepare lipophilic salts of inorganic anions. Relative to tetraethylammonium derivatives, tetrabutylammonium salts are more lipophilic but crystallize less readily. Derivatives Some tetrabutylammonium salts of simple anions include: * tetrabutylammonium fluoride, a desilylation reagent. *tetrabutylammonium bromide, a precursor to other tetrabutylammonium salts via salt metathesis reactions. *tetrabutylammonium iodide, a low cost catalyst. * tetrabutylammonium triiodide, a common carrier of the triiodide anion used in chemical synthesis. * tetrabutylammonium hydroxide, a precursor to other tetrabutylammonium salts via acid-base reactions. * tetrabutylammonium hexafluorophosphate, an electrolyte for nonaqueous electrochemistry. Some tetrabutylammonium salts of more complex examples include: * polyoxometalates. *NS. * metal carbonyl anions. *Synthetic iron-sulf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabutylammonium Bromide
Tetrabutylammonium bromide (TBAB) is a quaternary ammonium salt with a bromide commonly used as a phase transfer catalyst. It is used to prepare many other tetrabutylammonium salts by salt metathesis reactions. The anhydrous form is a white solid. In addition to being cheap, tetrabutylammonium bromide is also environmentally friendly, has a greater degree of selectivity, is operationally simple, non-corrosive, and can be recycled easily as well. Preparation and reactions Tetrabutylammonium bromide can be prepared by the alkylation of tributylamine with 1-bromobutane. Tetrabutylammonium bromide is used to prepare other salts of the tetrabutylammonium cation by salt metathesis reactions., , ;. It serves as a source of bromide ions for substitution reactions. It is one of a commonly-used phase transfer catalyst. As its melting point is just over 100 °C and decreases in the presence of other reagents, it can be considered an ionic liquid. Role in semi-clathrate formation TBAB ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetra-n-butylammonium Iodide
Tetra-''n''-butylammonium iodide (TBAI) is a quaternary ammonium salt with an iodide counterion. It is used for synthesizing tetra-''n''-butylammonium triiodide by mixing with iodine. Properties The solid crystal of tetra-''n''-butylammonium iodide is in the monoclinic crystal system. It has space group ''C''2/''c''. The unit cell has dimensions a=14.2806 b=14.1864 c=19.5951 β=111.149. There are eight formulae in the unit cell (Z=8), which has volume 3702.4 Å3. The enthalpy of formation ΔfH0 of tetra-''n''-butylammonium iodide is −499 kJ/mol, which is lower than that for the bromide or chloride (−540, −564 kJ/mol). At lower temperatures with water tetra-''n''-butylammonium iodide forms a clathrate hydrate. The tetra-''n''-butylammonium cation is large and hydrophobic. The absolute enthalpy of hydration (from gas phase) is −260 kJ/mol. The He(I) photoelectron spectrum of tetra-''n''-butylammonium iodide contains a peak at 11 eV due to the te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabutylammonium Hexafluorophosphate
Tetrabutylammonium hexafluorophosphate is a salt with the formula NBu4PF6. It is a white powder that is used as an electrolyte in nonaqueous electrochemistry. It is highly soluble in polar organic solvents such as acetone and acetonitrile. The salt consists of a positively charged tetrabutylammonium, a quaternary ammonia cation and a weakly basic hexafluorophosphate Hexafluorophosphate is an anion with chemical formula of . It is an octahedral species that imparts no color to its salts. is isoelectronic with sulfur hexafluoride, , and the hexafluorosilicate dianion, , and hexafluoroantimonate . In this an ... anion. These species are chemically inert, which allows the salt to serve as an inert electrolyte over a wide potential range. Given the sensitivity of electrochemical experiments, this salt is usually further purified, e.g., by recrystallization from aqueous or absolute ethanol. References {{Hexafluorophosphates Tetrabutylammonium salts Hexafluorophosphates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabutylammonium Fluoride
Tetra-''n''-butylammonium fluoride, commonly abbreviated to TBAF and ''n''-Bu4NF, is a quaternary ammonium salt with the chemical formula (CH3CH2CH2CH2)4N+F−. It is commercially available as the white solid trihydrate and as a solution in tetrahydrofuran. TBAF is used as a source of fluoride ion in organic solvents. Preparation and properties TBAF can be prepared by passing hydrofluoric acid through an ion-exchange resin, followed by tetrabutylammonium bromide. Upon evaporation of the water, TBAF can be collected as an oil in quantitative yield. Preparing anhydrous samples is of interest as the basicity of fluoride increases by more than 20 p''K'' units on passing from aqueous to aprotic solvent. However, heating samples of the hydrated material to 77 °C under vacuum causes decomposition to the hydrogen difluoride salt. Similarly, samples dried at 40 °C under high vacuum still contain 10-30 mol% of water and some 10% of difluoride. Instead, anhydrous TBAF ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabutylammonium Triiodide
Tetra-''n''-butylammonium triiodide (TBAI3) is a quaternary ammonium salt with a triiodide counterion. It is a common carrier of the triiodide used in chemical synthesis of photovoltaic materials, organic conductors and superconductors. In crystals, the triiodide moieties are linear and shows high crystallinity.{{Cite journal , last1=Brotherton , first1=Wendy S. , last2=Clark , first2=Ronald J. , last3=Zhu , first3=Lei , date=2012-08-03 , title=Synthesis of 5-Iodo-1,4-disubstituted-1,2,3-triazoles Mediated by in Situ Generated Copper(I) Catalyst and Electrophilic Triiodide Ion , url=https://doi.org/10.1021/jo300841c , journal=The Journal of Organic Chemistry , volume=77 , issue=15 , pages=6443–6455 , doi=10.1021/jo300841c , pmid=22780866 , issn=0022-3263 The crystals have a black appearance with a needle or plate-like habit. See also * Triiodide * Tetrabutylammonium tribromide * Organic superconductor An organic superconductor is a synthetic organic compound that exhibits su ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabutylammonium Hydroxide
Tetrabutylammonium hydroxide is the chemical compound with the formula (C4H9)4NOH, abbreviated Bu4NOH with the acronym TBAOH or TBAH. This species is employed as a solution in water or alcohols. It is a common base in organic chemistry. Relative to more conventional inorganic bases, such as KOH and NaOH, Bu4NOH is more soluble in organic solvents.. Preparation and reactions Solutions of Bu4NOH are usually prepared ''in situ'' from butylammonium halides, Bu4NX, for example by reacting them with silver oxide or using an ion exchange resin. Attempts to isolate Bu4NOH induces Hofmann elimination, leading to Bu3N and 1-butene. Solutions of Bu4NOH are typically contaminated with Bu3N for this reason. Treatment of Bu4NOH with a wide range of acids gives water and the other tetrabutylammonium salts: Bu4NOH + HX -> Bu4NX + H2O Applications Bu4NOH is a strong base that is used often under phase-transfer conditions to effect alkylations and deprotonations. Typical reactions include benz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Ammonium Cation
In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds (called quaternary amines in oilfield parlance) are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule. Quats are used in consumer applications including as antimicrobials (such as detergents and disinfectants), fabric softeners, and hair conditioners. As an antimicrobial, they are able to inactivate enveloped viruses (such as SARS-CoV-2). Quats tend to be gentler on surfaces than bleach-based disinfectants, and are generally fabric-safe. Synthesis Quaternary ammonium comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyoxometalate
In chemistry, a polyoxometalate (abbreviated POM) is a polyatomic ion, usually an anion, that consists of three or more transition metal oxyanions linked together by shared oxygen atoms to form closed 3-dimensional frameworks. The metal atoms are usually group 6 (Mo, W) or less commonly group 5 ( V, Nb, Ta) transition metals and Tc in their high oxidation states. Polyoxometalates are often colorless, orange or red diamagnetic anions. Two broad families are recognized, isopolymetalates, composed of only one kind of metal and oxide, and heteropolymetalates, composed of one metal, oxide, and a main group oxyanion (phosphate, silicate, etc.). Many exceptions to these general statements exist. Formation The oxides of d0 metals such as , , dissolve at high pH to give orthometalates, , , . For and , the nature of the dissolved species at high pH is less clear, but these oxides also form polyoxometalates. As the pH is lowered, orthometalates protonate to give oxide–hydroxide co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Octachlorodirhenate
Potassium octachlorodirhenate(III) is an inorganic compound with the formula Potassium, K2Rhenium, Re2Chlorine, Cl8. This dark blue salt (chemistry), salt is well known as an early example of a compound featuring quadruple bond between its metal centers. Although the compound has no practical value, its characterization was significant in opening a new field of research into coordination complex, complexes with quadruple bonds. Synthesis and reactions Soviet chemists first reported K2[Re2Cl8] in 1954, but it was not until 1964 that F. Albert Cotton, Cotton and Harris characterized the compound as featuring a short Re–Re bond, the first of its kind discovered. The results of this classic study subsequently led to new work into other metals capable of forming metal–metal bonds, such as chromium, molybdenum, tungsten, and technetium. A high-yield synthesis of the tetrabutylammonium salt involves treating the perrhenate salt with benzoyl chloride followed by HCl: :2 [(n-But ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Ammonium Compounds
In chemistry, quaternary ammonium cations, also known as quats, are positively charged polyatomic ions of the structure , R being an alkyl group or an aryl group. Unlike the ammonium ion () and the primary, secondary, or tertiary ammonium cations, the quaternary ammonium cations are permanently charged, independent of the pH of their solution. Quaternary ammonium salts or quaternary ammonium compounds (called quaternary amines in oilfield parlance) are salts of quaternary ammonium cations. Polyquats are a variety of engineered polymer forms which provide multiple quat molecules within a larger molecule. Quats are used in consumer applications including as antimicrobials (such as detergents and disinfectants), fabric softeners, and hair conditioners. As an antimicrobial, they are able to inactivate enveloped viruses (such as SARS-CoV-2). Quats tend to be gentler on surfaces than bleach-based disinfectants, and are generally fabric-safe. Synthesis Quaternary ammonium compo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetraethylammonium
Tetraethylammonium (TEA), () or (Et4N+) is a quaternary ammonium cation consisting of four ethyl groups attached to a central nitrogen atom, and is positively charged. It is a counterion used in the research laboratory to prepare lipophilic salts of inorganic anions. It is used similarly to tetrabutylammonium, the difference being that its salts are less lipophilic and more easily crystallized. Preparation The chloride salt is prepared by the reaction of triethylamine and an ethyl halide: :Et3N + EtX → Et4N+X− This method works well for the preparation of tetraethylammonium iodide (where X = I). Most tetraethylammonium salts are prepared by salt metathesis reactions. For example, the synthesis of tetraethylammonium perchlorate, a salt that has been useful as a supporting electrolyte for polarographic studies in non-aqueous solvents, is carried out by mixing the water-soluble salts tetraethylammonium bromide and sodium perchlorate in water, from which the water-insoluble tetr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Desilylation
Silylation is the introduction of one or more (usually) substituted silyl groups (R3Si) to a molecule. The process is the basis of organosilicon chemistry. Of organic compounds Alcohols, carboxylic acids, amines, thiols, and phosphates can be silylated. The process involves the replacement of a proton with a trialkylsilyl group, typically trimethylsilyl (-SiMe3). Generally the substrate is deprotonated with a suitable strong base followed by treatment with a silyl chloride (e.g. trimethylsilyl chloride). Often strong bases such butyl lithium or a Grignard reagent are used, as illustrated by the synthesis of a trimethylsilyl ethers as protecting groups from an alcohol: :ROH + BuLi → ROLi + BuH :ROLi + Me3SiCl → ROSiMe3 + LiCl Bis(trimethylsilyl)acetamide ("BSA", Me3SiNC(OSiMe3)Me is an efficient silylation agent used for the derivatisation of compounds. The reaction of BSA with alcohols gives the corresponding trimethylsilyl ether, together with N-(trimethylsilyl)acetamide as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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