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  • ions
  • An eco-friendly and economic process capable to replace current industrial production via oxidation of bromide ions using gaseous chlorine is highly desirable, he explained opening his presentation. (rsc.org)
  • Transition metal ions, due to their multiple oxidation states, were the only elements capable of controlling the oxidation states of such molecules, and thus were selected for. (wikipedia.org)
  • electrons
  • Irrespective of scan rate, the area under the peak (in units of AV) is equal to n F A Γ ν {\displaystyle nFA\Gamma \nu } , where n {\displaystyle n} is the number of electrons exchanged in the oxidation/reduction of the center, A {\displaystyle A} is the electrode surface and Γ {\displaystyle \Gamma } is the electroactive coverage (in units of mol/cm2). (wikipedia.org)
  • anaerobic
  • The use of Polysulfides is a type of abiotic reduction and works best in anaerobic conditions where iron (III) is available. (wikipedia.org)
  • The different anaerobic, autocatalysed, reductive, metabolic pathways seen in the earliest known cells developed in separate energised vesicles, protocells, where they were produced cooperatively with certain bases of the nucleic acids. (wikipedia.org)
  • involve
  • Reductive elimination is often seen in higher oxidation states, and can involve a two-electron change at a single metal center (mononuclear) or a one-electron change at each of two metal centers (binuclear, dinuclear, or bimetallic). (wikipedia.org)
  • Reductions with samarium(II) iodide involve the conversion of various classes of organic compounds into reduced products through the action of samarium(II) iodide, a mild one-electron reducing agent. (wikipedia.org)
  • carbonyl
  • Carbonyl reduction of [carbonyl-14C]NNK with either sodium borohydride or cultured rat liver slices gave [carbinol-14C] 4-(methylnitrosamino)-1-(3-pyridyl) butan-1-ol. (wikipedia.org)
  • In the presence of a proton source, however, the dimer may undergo either disproportionation to form a samarium alkoxide and carbonyl compound, or protonation to form a carbinol radical ii followed by a second reduction and protonation, yielding an alcohol. (wikipedia.org)
  • chemistry
  • Reductive elimination is an elementary step in organometallic chemistry in which the oxidation state of the metal center decreases while forming a new covalent bond between two ligands. (wikipedia.org)
  • Gillham and Tratnyek in particular applied the reductive chemistry to groundwater treatment with the emplacement of ZVI barriers. (wikipedia.org)
  • The prebiotic chemistry of life had to be reductive in order to obtain, e.g. (wikipedia.org)
  • This effect is mainly caused by the surrounding ligands that are complexed to the metal and it is the ligands that are involved in the reduction chemistry instead of the metal due to electronic destabilization by being significantly distanced from the metal. (wikipedia.org)
  • decarboxylation
  • 2) Diimide is typically generated either through the oxidation of hydrazine or the decarboxylation of potassium azodicarboxylate. (wikipedia.org)
  • The most synthetically useful methods are: Oxidation of hydrazine with oxygen, in the presence of a copper(II) catalyst and/or a carboxylic acid Decarboxylation of dipotassium azodicarboxylate in the presence of an acid Thermal decomposition of sulfonylhydrazides Procedures (particularly those employing air as an oxidant) are typically straightforward and do not require special handling techniques. (wikipedia.org)
  • A decarboxylation leads to the release of CO2 and the reduction of the cluster. (wikipedia.org)
  • Reactivity
  • This type of reactivity is generally seen with first row metals, which prefer a one-unit change in oxidation state, but has been observed in both second and third row metals. (wikipedia.org)
  • However, steric factors must also be considered on the reactivity of the Sm(III) complex as less crowded structures do not have any reductive activity. (wikipedia.org)
  • molecules
  • One way to accomplish this is to apply a voltage to the surface, resulting in either reduction or oxidation of the adsorbed molecule (depending on the bias and the adsorbed molecules). (wikipedia.org)
  • However, atmospheric oxygen levels increased considerably, and it was then necessary for cells to have control over the reduction and oxidation of such small molecules in order to build and break down cells when necessary, without the inevitable oxidation (breaking down) of everything. (wikipedia.org)
  • oxygen
  • Technically speaking, oxidation is the process of a compound picking up an oxygen atom and reduction is the process by which a compound loses an oxygen atom. (specsfinewine.com)
  • Metal exchange with the hydrosilane produces a silyl peroxide product and further reduction (via homolysis of the oxygen-oxygen bond) leads to the product alcohol. (wikipedia.org)
  • process
  • The barrel-aging process encourages a "controlled oxidation" as a small amount of wine (called the angels' share) evaporates out and air works in through the staves. (specsfinewine.com)
  • It is the mirror process of In Situ Chemical Oxidation (ISCO). (wikipedia.org)
  • Oftentimes, in searching for the shortest, most efficient synthetic route, process chemists must devise creative synthetic solutions that eliminate costly functional group manipulations and oxidation/reduction steps. (wikipedia.org)
  • either
  • If little or no "air effect" or oxidation is desired, the wine is either bottled very young or kept in tanks to age before bottling. (specsfinewine.com)
  • A second reduction immediately follows, after which either protonation or elimination-tautomerization affords the product. (wikipedia.org)
  • complexes
  • First-row metal complexes tend to undergo reductive elimination faster than second-row metal complexes, which tend to be faster than third-row metal complexes. (wikipedia.org)
  • typically
  • Samarium iodide is a one-electron reductant, and typically effects reduction through a series of electron transfer and proton transfer (from protic solvent) steps. (wikipedia.org)
  • chemical
  • In situ chemical reduction (ISCR) is a new type of environmental remediation technique used for soil and/or groundwater remediation to reduce the concentrations of targeted environmental contaminants to acceptable levels. (wikipedia.org)
  • ISCR is usually applied in the environment by injecting chemically reductive additives in liquid form into the contaminated area or placing a solid medium of chemical reductants in the path of a contaminant plume. (wikipedia.org)
  • naturally
  • These substances are very interesting because they are naturally present, and learning about how they produce reductive zones could lead to the development of better reductants for ISCR. (wikipedia.org)
  • yields
  • Unfortunately, this means that in the case of alkyne reduction, over-reduction to the alkane can occur resulting in diminished yields where the cis alkene is the desired product. (wikipedia.org)
  • species
  • Ionic liquids are thermally stable, have negligible vapor pressure, and are electrochemically stable at negative potentials that encompass the reduction potential of actinide species. (dissertation.com)
  • The reduction/oxidation of soluble cerium and uranium (uranyl) species in IL is examined at Au, Pt, and GC (glassy carbon) electrodes. (dissertation.com)
  • allows
  • If managed properly with careful elevage, oxidation at this level is all good as it allows the wine to develop and gets rid of any reductive character the wine might have before bottling. (specsfinewine.com)
  • although
  • Compared to cork, screw caps reduce the wine faults of oxidation and of cork taint, although it is possible to find TCA contamination in a screw cap bottle. (wikipedia.org)
  • Scientists have also found that certain iron minerals, like green rust, magnetite, and pyrite, also have reductive capabilities although they contain ferrous iron rather than ZVI. (wikipedia.org)
  • wine
  • If some oxidation is desired (as for many great whites and almost all great reds), the wine is put into barrels for a period of aging before the final blending (or assemblage) and bottling. (specsfinewine.com)
  • negative
  • In a voltammetric experiment carried out with an adsorbed redox protein, the oxidation and reduction of each redox site shows as a pair of positive and negative peaks. (wikipedia.org)
  • Around 4 Ga , the acidic seawater contained high amounts of H2S and thus created a reducing environment with a potential of around -0.2 V. So any element that had a large negative value with respect to the reduction potential of the environment was available in its free ionic form and can subsequently be incorporated into cells, i.e. (wikipedia.org)
  • faster
  • Additionally, electron-poor metal centers undergo reductive elimination faster than electron-rich metal centers since the resulting metal would gain electron density upon reductive elimination. (wikipedia.org)
  • lead
  • For example, a lower salinity is thought to lead to more retention of Fe-oxide-bound P in sediments because of a lower availability of sulfate (SO 4 2− ), and associated lower rates of SO 4 2− reduction and sulfide(HS − )-induced reduction of Fe-oxides (e.g. (springer.com)
  • another
  • Additionally, mononuclear reductive elimination requires that the groups being eliminated must be cis to one another on the metal center. (wikipedia.org)
  • Reactions
  • Overcoming the "Oxidant Problem": Strategies to Use O 2 as the Oxidant in Organometallic C-H Oxidation Reactions Catalyzed by Pd (and Cu). (wisc.edu)
  • Palladium-Catalyzed Oxidation Reactions: Comparison of Benzoquinone and Molecular Oxygen as Stoichiometric Oxidants. (wisc.edu)
  • These included combustion and acid-base neutralization (using invisible inks), redox (including plating reactions and showing changes in pigment with oxidation state), and polymerization reactions (used, for example, in making classical guitar strings). (uky.edu)
  • Although oxidation reactions are commonly associated with the formation of oxides from oxygen molecules, oxygen is not necessarily included in such reactions, as other chemical species can serve the same function. (wikipedia.org)
  • The term "hydrogenation" could be used instead of reduction, since hydrogen is the reducing agent in a large number of reactions, especially in organic chemistry and biochemistry. (wikipedia.org)
  • But, unlike oxidation, which has been generalized beyond its root element, hydrogenation has maintained its specific connection to reactions that add hydrogen to another substance (e.g., the hydrogenation of unsaturated fats into saturated fats, R−CH=CH−R + H2 → R−CH2−CH2−R). The word "redox" was first used in 1928. (wikipedia.org)
  • The oxidation alone and the reduction alone are each called a half-reaction, because two half-reactions always occur together to form a whole reaction. (wikipedia.org)
  • In practice, the transfer of electrons will always cause a change in oxidation state, but there are many reactions that are classed as "redox" even though no electron transfer occurs (such as those involving covalent bonds). (wikipedia.org)
  • It has recently been investigated and determined that tripyrrolidinophosphoric acid triamide (TPPA) can be used in lieu of HMPA as an activator for SmI2 reductions, producing faster reactions and similar yields while avoiding the use of a known carcinogen. (wikipedia.org)
  • Alcohol Oxidation
  • 2i In the course of these studies, it was found that carbonyl allylation could be achieved directly from the alcohol oxidation level by way of allene-alcohol transfer hydrogenation, 2i constituting a novel variant of hydrogen auto-transfer processes wherein hydrogen exchange between reactants is used to generate nucleophile-electrophile pairs ( Scheme 1 ). (pubmedcentralcanada.ca)
  • alkylation
  • A simple and convenient procedure enables the reductive alkylation of primary and secondary amines and N,N-dimethylation of amino acids using sodium borohydride as reducing agent in 2,2,2- trifluoroethanol without use of a catalyst or any other additive. (organic-chemistry.org)
  • wastewater
  • The proposed method can be considered as one of the significant strategies for reduction or destruction of hormones from wastewater due to the non-generation of dangerous by- products and the low energy consumption. (deepdyve.com)
  • Keywords: Estrogens, Ultrasound, Wastewater, Reduction, Hormones Introduction 1980 that the detrimental impacts of these hormones Estrogens are one of the micro-pollutants in wastewater were confirmed on fish growth (Behera et al. (deepdyve.com)
  • In a study in The aim of this study was to investigate the effect of Brazil in 2012, E1 and E2 concentrations in raw waste- ultrasound on the reduction of sewage hormones from water were determined 566 and 143 ng/L, respectively wastewater and not effluent. (deepdyve.com)
  • elimination
  • Electrochemical oxidation by means of boron-doped diamond (BDD) anodes generates a very efficient oxidizing environment by forming hydroxyl radicals, providing effective water purification for elimination of persistent pollutants. (environmental-expert.com)
  • In demercuration, the acetoxymercury group is replaced with a hydrogen in a stereochemically insensitive reaction known as reductive elimination. (wikipedia.org)
  • Complex B reacts in a transmetallation with the copper acetylide, complex F, which is produced in the copper cycle, to give complex C, expelling the copper halide, complex G. Both organic ligands are trans oriented and convert to cis in a trans-cis isomerization to produce complex D. In the final step, complex D undergoes reductive elimination to produce the alkyne, with regeneration of the palladium catalyst. (wikipedia.org)
  • A second reduction immediately follows, after which either protonation or elimination-tautomerization affords the product. (wikipedia.org)
  • atoms
  • The oxidation state of an atom is the fictitious charge that an atom would have if all bonds between atoms of different elements were 100% ionic. (wikipedia.org)
  • carbonyl
  • Under related transfer hydrogenation conditions employing isopropanol as terminal reductant, identical carbonyl adducts 1c-9c are obtained from the aldehyde oxidation level. (pubmedcentralcanada.ca)
  • In the presence of a proton source, however, the dimer may undergo either disproportionation to form a samarium alkoxide and carbonyl compound, or protonation to form a carbinol radical ii followed by a second reduction and protonation, yielding an alcohol. (wikipedia.org)
  • occur
  • If a substituent is present in the β position of the alkyl halide, reductive fragmentation to a diastereomeric mixture of alkenes may occur. (wikipedia.org)
  • carbon
  • Tyrosine can either undergo a decarboxylation via tyrosine decarboxylase to generate tyramine and subsequently undergo an oxidation at carbon 3 by a monophenol hydroxylase or first be hydroxylated by tyrosine hydroxylase to form L-DOPA and decarboxylated by DOPA decarboxylase. (wikipedia.org)
  • reductant
  • 2h Though effective for reverse prenylation, attempted crotylations and allylations using gaseous hydrogen as the terminal reductant suffered from over-reduction of the olefinic adduct. (pubmedcentralcanada.ca)
  • To address this limitation, allene-aldehyde reductive coupling was performed under the conditions of transfer hydrogenation using isopropanol as the terminal reductant. (pubmedcentralcanada.ca)
  • oxygen
  • The word oxidation originally implied reaction with oxygen to form an oxide, since dioxygen (O2 (g)) was historically the first recognized oxidizing agent. (wikipedia.org)
  • The rarity of tellurium on Earth is thought to be caused by conditions during the formation of the Earth, when the stable form of certain elements, in the absence of oxygen and water, was controlled by the reductive power of free hydrogen. (wikipedia.org)
  • allows
  • The use of hexamethylphosphoramide (HMPA) as a co-solvent in samarium iodide reductions allows the reaction to be carried out under much milder conditions than in its absence. (wikipedia.org)
  • species
  • The nonenzymatic pathway for nitrite reconversion to NO requires another peculiarity of the microenvironment, namely a reduced pH, to favor the acidic reduction (disproportionation) of nitrite species ( 19 - 21 ). (aacrjournals.org)
  • However
  • However, alkyl halide reductions employing HMPA as a co-solvent likely involve a large proportion of organosamarium intermediates. (wikipedia.org)
  • Upon
  • The word reduction originally referred to the loss in weight upon heating a metallic ore such as a metal oxide to extract the metal. (wikipedia.org)
  • power
  • Also, the frequency and power of ultrasound had a significant effect on reduction efficiency of hormones while the exposure had no significant effect. (deepdyve.com)
  • known
  • S. oneidensis MR-1 belongs to a class of bacteria known as "Dissimilatory Metal-Reducing Bacteria (DMRB)" because of their ability to couple metal reduction with their metabolism. (wikipedia.org)
  • present
  • In the present study, Electrochemical Oxidation was used to remove COD and color from semi-aerobic landfill leachate collected from Pulau Burung Landfill Site (PBLS), Penang, Malaysia. (environmental-expert.com)
  • Chemical
  • Roudbari and Rezakazemi AMB Expr (2018) 8:91 Page 2 of 8 researchers and national and regional authorities to them elastic skin and reduction of organic chemical pollutants and several studies have been conducted to determine from liquid environments (Mahravan et al. (deepdyve.com)
  • excellent
  • An expeditious and practical method for the reduction of various amides and lactams to amines in good to excellent yields is consisted of activation with Tf 2 O followed by reduction with sodium borohydride in THF at room temperature. (organic-chemistry.org)
  • metal
  • The means of reducing the metals is of particular controversy, as research using scanning electron microscopy and transmission electron miicroscopy revealed abnormal structural protrusions resembling bacterial filaments that are thought to be involved in the metal reduction. (wikipedia.org)