- Water Compatible Hypophosphites- d2 Reagents: Deuteration Reaction via Deutero-deiodination in Aqueous Solution
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Contrary to conventional deuteration approaches which typically entail deuterated solvents and/or moisture exclusion, an unprecedented deutero-deiodination reaction attainable in aqueous (H2O) solution is presented herein. By utilizing the stability of inorganic deuterated calcium/sodium hypophosphites against wayward H/D isotopic exchange within pH 2.5-11.7, these shelf-stable, nontoxic, cost-effective, and environmentally benign deuteration reagents mediate deuteration of a broad range alkyl and aryl iodides with ample isotopic incorporation in aqueous (H2O) solution.
- Fang, Jing,Li, Ting,Meng, Lingkui,Song, Zejin,Wan, Qian,Zeng, Jing,Zhao, Xiang
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supporting information
(2020/03/13)
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- Oxidation of lower oxyacids of phosphorus by tetraethylammonium chlorochromate: A kinetic and mechanistic study
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Oxidation of lower oxyacids of phosphorus by tetraethylammonium chlorochromate in dimethyl sulphoxide leads to the formation of corresponding oxyacids with phosphorus in a higher oxidation state. The reaction exhibits 1:1 stoichiometry. The reaction is first order each with respect to chlorochromate and the oxyacids. The reaction does not induce polymerization of acrylonitrile. The oxidation of deuterated phosphinic and phosphorous acids exhibits a substantial primary kinetic isotope effect. The oxidation has been studied in nineteen different organic solvents. The effect of solvent indicates that the solvent polarity plays a major role in the process. It has been shown that the pentacoordinated tautomer of the phosphorus oxyacid is the reactive reductant and the tricoordinated form of phosphorus oxyacids does not participate in the oxidation process. A mechanism involving transfer of a hydride ion in the rate determining step has been proposed.
- Vadera, Khushboo,Sharma,Agarwal,Sharma, Pradeep K.
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p. 302 - 306
(2011/01/10)
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- Oxidation of white phosphorus by peroxides in aqueous and alcoholic solutions: mechanistic aspects and catalytic studies
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The oxidation of white phosphorus by hydrogen peroxide or different organic peroxides (such as tert-butyl hydroperoxide, dibenzoylperoxide, 3-chloroperoxybenzoic acid) has been studied in both aqueous and alcoholic solutions under anaerobic conditions. De
- Akbayeva, Dina N.,Faisova, Farida Kh.,Abdreimova, Rumia R.,Peruzzini, Maurizio
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p. 181 - 193
(2008/10/09)
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- Radical reaction by a combination of phosphinic acid and a base in aqueous media
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Treatment of various organic halides with phosphinic acid (hypophosphorous acid) in aqueous ethanol in the presence of a radical initiator and a base gave the corresponding reduced products in high yields. Addition of a base is indispensable for the reduction of halides by phosphinic acid. Allylic ether of o-iodophenol or 2-haloalkanal allylic acetal underwent radical cyclization under the same conditions to afford the corresponding cyclic product in excellent yield. Deuterated phosphinic acid was found to be an efficient chain carrier for the radical deuteration of organic halides. For example, a deuterium oxide solution of deuterated phosphinic acid, potassium carbonate, 2,2′-azobis(isobutyramidine) dihydrochloride as an initiator, and p-iodobenzoic acid was heated at reflux to give p-deuteriobenzoic acid in 94% yield. A mixed dioxane/D2O solvent system combined with DBU and potassium peroxodisulfate was crucial to deuterate hydrophobic substrates in high yields and with high deuterium incorporation. Complete deuterium incorporation was accomplished only by the reaction in D2O without an organic cosolvent and an organic base.
- Yorimitsu,Shinokubo,Oshima
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p. 225 - 235
(2007/10/03)
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- Kinetics and Mechanism of the Oxidation of Phosphinic, Phenylphosphinic, and Phosphorous Acids by Pyridinium Fluorotrioxochromate(VI)
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Oxidation of the lower phosphorus oxyacids by results in the formation of corresponding oxyacids in the higher valence states.The reaction is first order with respect to the oxidant concentration.A Michaelis-Menten type kinetics was observed with respect to the substrate, indicating the formation of a complex in a pre-equilibrium.The formation constants and the rates of disproportionation of the complexes have been evaluated at different temperatures.The reaction exhibits a substantial primary kinetic isotope effect.The rates in 19 different organicsolvents have been analysed using Kamlet-Taft and Swain equations.It has been found that the cation-solvating power of the solvents plays an important role.It is proposed that the 'inactive ' tautomer of the phosphorus oxyacids is the reactive reductant, and that transfer of a hydride ion from the P-H bond to the oxidant in the rate-determining step occurs.
- Moondra, Anu,Mathur, Abha,Banerji, Kalyan K.
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p. 2697 - 2700
(2007/10/02)
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