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Bobbitt's Salt
Bobbitt's salt is an oxoammonium compound derived from 4-acetamido-2,2,6,6-tetramethylpiperidine. It contains the tetrafluoroborate anion and is named after the American chemist James M. Bobbitt. As a less expensive analogue of the ''N''-oxoammonium salt derived from TEMPO, Bobbitt's salt is still mainly used as a catalyst for oxoammonium-catalyzed oxidations. ''(7)'' References External links *{{Commonscatinline, Bobbitt's salt Tetrafluoroborates Acetamides Oxycations ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrafluoroborate
Tetrafluoroborate is the anion . This tetrahedral species is isoelectronic with tetrafluoroberyllate (), tetrafluoromethane (CF4), and tetrafluoroammonium () and is valence isoelectronic with many stable and important species including the perchlorate anion, , which is used in similar ways in the laboratory. It arises by the reaction of fluoride salts with the Lewis acid BF3, treatment of tetrafluoroboric acid with base, or by treatment of boric acid with hydrofluoric acid. As an anion in inorganic and organic chemistry The popularization of has led to decreased use of in the laboratory as a weakly coordinating anion. With organic compounds, especially amine derivatives, forms potentially explosive derivatives. Disadvantages to include its slight sensitivity to hydrolysis and decomposition via loss of a fluoride ligand, whereas does not suffer from these problems. Safety considerations, however, overshadow this inconvenience. With a formula weight of 86.8, BF is also conveni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James M
James is a common English language surname and given name: *James (name), the typically masculine first name James * James (surname), various people with the last name James James or James City may also refer to: People * King James (other), various kings named James * Saint James (other) * James (musician) * James, brother of Jesus Places Canada * James Bay, a large body of water * James, Ontario United Kingdom * James College, a college of the University of York United States * James, Georgia, an unincorporated community * James, Iowa, an unincorporated community * James City, North Carolina * James City County, Virginia ** James City (Virginia Company) ** James City Shire * James City, Pennsylvania * St. James City, Florida Arts, entertainment, and media * ''James'' (2005 film), a Bollywood film * ''James'' (2008 film), an Irish short film * ''James'' (2022 film), an Indian Kannada-language film * James the Red Engine, a character in ''Thomas the Tank En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-Oxoammonium Salt
''N''-Oxoammonium salts are a class of organic compounds with the formula 1R2=O−. The cation 1R2=Ois of interest for the dehydrogenation of alcohols. Oxoammonium salts are diamagnetic, whereas the nitroxide has a doublet ground state. A prominent nitroxide is prepared by oxidation of (2,2,6,6-tetramethylpiperidin-1-yl)oxyl, commonly referred to as EMPOsup>+. A less expensive analogue is Bobbitt's salt. Structure and bonding Oxoammonium cations are isoelectronic with carbonyls and structurally related to aldoximes (hydroxylamines), and aminoxyl (nitroxide) radicals, with which they can interconvert via a series of redox steps. According to X-ray crystallography, the N–O distance in EMPOF4 is 1.184 Å, 0.1 Å shorter than the N–O distance of 1.284 Å in the charge-neutral TEMPO. Similarly, the N in EMPOsup>+ is nearly planar, but the O moves 0.1765 Å out of the plane in the neutral TEMPO. The ''N''-oxoammonium salts are used for oxidation of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TEMPO
In musical terminology, tempo (Italian, 'time'; plural ''tempos'', or ''tempi'' from the Italian plural) is the speed or pace of a given piece. In classical music, tempo is typically indicated with an instruction at the start of a piece (often using conventional Italian terms) and is usually measured in beats per minute (or bpm). In modern classical compositions, a "metronome mark" in beats per minute may supplement or replace the normal tempo marking, while in modern genres like electronic dance music, tempo will typically simply be stated in BPM. Tempo may be separated from articulation and meter, or these aspects may be indicated along with tempo, all contributing to the overall texture. While the ability to hold a steady tempo is a vital skill for a musical performer, tempo is changeable. Depending on the genre of a piece of music and the performers' interpretation, a piece may be played with slight tempo rubato or drastic variances. In ensembles, the tempo is often ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxoammonium-catalyzed Oxidation
Oxoammonium-catalyzed oxidation reactions involve the conversion of organic substrates to more highly oxidized materials through the action of an N-oxoammonium species. Nitroxides may also be used in catalytic amounts in the presence of a stoichiometric amount of a terminal oxidant. Bobbitt, J. M.; Bruckner, C.; Merbouh, N. '' Org. React.'' 2009, ''74'', 103. Nitroxide radical species used are either 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) or derivatives thereof. Mechanism and stereochemistry One-electron oxidation of the nitroxide produces a highly electrophilic oxoammonium species, which serves as the active oxidizing agent. The nitroxide can be used as a catalyst in conjunction with cheaper stoichiometric oxidants such as sodium hypochlorite or bis(acetoxy)iodobenzene (BAIB). Under neutral or slightly acidic conditions (in the presence of silica gel, for instance), oxidation occurs by an initial hydrogen bond between the hydroxyl group and the oxoammonium nitrogen, fol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetamides
Acetamide (systematic name: ethanamide) is an organic compound with the formula CH3CONH2. It is the simplest amide derived from acetic acid. It finds some use as a plasticizer and as an industrial solvent. The related compound ''N'',''N''-dimethylacetamide (DMA) is more widely used, but it is not prepared from acetamide. Acetamide can be considered an intermediate between acetone, which has two methyl (CH3) groups either side of the carbonyl (CO), and urea which has two amide (NH2) groups in those locations. Acetamide is also a naturally occurring mineral with the IMA symbol: Ace. Production Laboratory scale Acetamide can be produced in the laboratory from ammonium acetate by dehydration: : H4CH3CO2] → CH3C(O)NH2 + H2O Alternatively acetamide can be obtained in excellent yield via ammonolysis of acetylacetone under conditions commonly used in reductive amination. It can also be made from anhydrous acetic acid, acetonitrile and very well dried hydrogen chloride gas, using a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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