2345-27-9Relevant academic research and scientific papers
Hyperfine Structures of Doxyl-Labeled n-Alkyl Chains by NMR and EPR
Bales, Barney L.,Mareno, Donna,Harris, Francis L.
, p. 37 - 53 (1993)
The proton hyperfine coupling constants in a series of n-alkyl chains with a doxyl group attached at various points from the end of the chain have been measured by NMR and EPR spectroscopies.The hyperfine structure shows no further change when the attachment point is four or more carbon-carbon bonds from the end of the chain.The high resolution afforded by 500 MHz NMR reveals small magnetic inequivalencies in the chain methylene hyperfine coupling constants located at the same distance from the attachment point.Protons in the same chain methylene group are shown to have different hyperfine coupling constants while protons on different chain methylene groups, symmetrically placed with respect to attachment point, are the same, in every case except one.EPR spectra simulated from hyperfine coupling constants derived from NMR are in excellent agreement with experiment.Inhomogeneous EPR line broadening is found to be in excellent agreement with a previously derived universal hyperfine pattern (B.L.Bales, in "Biological Magnetic Resonance" (L.J.Berliner and J.Reuben, Eds.), Vol. 8, p. 77, Plenum, New York, 1989), so no new correction procedures are necessary.Strategies for selectively deuterating n-alkyl spin probes are developed and compared with some results taken from the literature.Deuterating the chain methylene groups two to three carbon-carbon bonds from the attachment point is necessary for the maximum gain in resolution and sensitivity.
METHOD FOR CONVERTING HYDROXYL GROUP OF ALCOHOL
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Paragraph 0370, (2021/02/19)
The present invention relates to: a method for converting a hydroxyl group of an alcohol; and a catalyst which makes the method possible. A method for converting a hydroxyl group of an alcohol according to the present invention is characterized by producing a compound represented by CH(R1)(R2)Nu (wherein R1, R2 and Nu are as defined below) by reacting an alcohol represented by CH(R1)(R2)OH (wherein each of R1 and R2 represents a hydrogen atom, an optionally substituted alkyl group, or the like) and a compound having an active proton, which is represented by H-Nu (wherein Nu represents a group represented by —CHX1-EWG1 or —NR3R4; X1 represents a hydrogen atom or the like; EWG1 represents an electron-withdrawing group; and each of R3 and R4 represents a hydrogen atom, an optionally substituted alkyl group, or the like), with each other in the presence of a complex of a group 7-11 metal of the periodic table and at least one solid base that is selected from the group consisting of layered double hydroxides, composite oxides and calcium hydroxide.
MnO2as a terminal oxidant in Wacker oxidation of homoallyl alcohols and terminal olefins
Fernandes, Rodney A.,Ramakrishna, Gujjula V.,Bethi, Venkati
, p. 6115 - 6125 (2020/10/27)
Efficient and mild reaction conditions for Wacker-type oxidation of terminal olefins of less explored homoallyl alcohols to β-hydroxy-methyl ketones have been developed by using a Pd(ii) catalyst and MnO2 as a co-oxidant. The method involves mild reaction conditions and shows good functional group compatibility along with high regio- and chemoselectivity. While our earlier system of PdCl2/CrO3/HCl produced α,β-unsaturated ketones from homoallyl alcohols, the present method provided orthogonally the β-hydroxy-methyl ketones. No overoxidation or elimination of benzylic and/or β-hydroxy groups was observed. The method could be extended to the oxidation of simple terminal olefins as well, to methyl ketones, displaying its versatility. An application to the regioselective synthesis of gingerol is demonstrated.
Catalytic Wacker-type Oxidations Using Visible Light Photoredox Catalysis
Ho, Yee Ann,Paffenholz, Eva,Kim, Hyun Jin,Orgis, Benjamin,Rueping, Magnus,Fabry, David C.
, p. 1889 - 1892 (2019/03/17)
A combined palladium/photoredox catalytic system for the efficient oxidation of terminal olefins to the corresponding methyl ketones is presented. The interplay of air, water, and light leads to a protocol in which the stoichiometric oxidants required for oxidative palladium catalysis are substituted with catalytic, single-electron transfer processes. Detailed mechanistic investigations revealed the role of the key components, in situ generated species, and catalysts. A broad range of substrates was examined in homogeneous as well as heterogeneous photoredox protocols, delivering the desired products in good yields.
Highly practical and efficient preparation of aldehydes and ketones from aerobic oxidation of alcohols with an inorganic-ligand supported iodine catalyst
Zhang, Mengqi,Zhai, Yongyan,Ru, Shi,Zang, Dejin,Han, Sheng,Yu, Han,Wei, Yongge
supporting information, p. 10164 - 10167 (2018/09/13)
Herein, we divulge an efficient protocol for aerobic oxidation of alcohols with an inorganic-ligand supported iodine catalyst, (NH4)5[IMo6O24]. The catalyst system is compatible with a wide range of groups and exhibits high selectivity, and shows excellent stability and reusability, thus serving as a potentially greener alternative to the classical transformations.
Stereoselective divergent synthesis of 1,2-aminoalcohol-containing heterocycles from a common chiral nonracemic building block
Géant, Pierre-Yves,Grenet, Erwann,Martínez, Jean,Salom-Roig, Xavier J.
, p. 22 - 30 (2015/12/31)
γ-N,N-Dibenzylamino-β-hydroxysulfoxide 1 proved to be an excellent chiral building block for the synthesis of a range of 1,2-amino alcohol-containing heterocycles. Thus, 1 was converted into 4,5-disubstuted oxazolidin-2-one 4 and aminoepoxides 2 and 3. Aminoepoxide 2 proved to be an excellent precursor to access oxazolidin-2-one 5 and azetidin-3-ol 6. Finally, 2 was used as a key intermediate that allowed the development of a divergent strategy to access cis-2-methyl-6-substituted piperidin-3-ol alkaloids. (+)-Deoxocassine 7 and a C-6 ethyl analogue 8 were prepared to illustrate this approach and to demonstrate that this strategy should be adaptable to the production of other members of this alkaloid family.
Hypervalent Iodine as a Terminal Oxidant in Wacker-Type Oxidation of Terminal Olefins to Methyl Ketones
Chaudhari, Dipali A.,Fernandes, Rodney A.
, p. 2113 - 2121 (2016/03/15)
A mimic of the Wacker process for C=O bond formation in terminal olefins can be initiated by a combination of the Pd(II) and hypervalent iodine reagent, Dess-Martin periodinane to generate methyl ketones. This operationally simple and scalable method offers Markovnikov selectivity, has good functional group compatibility, and is mild and high yielding.
A functionalized phosphine merit preparation of ionic liquids and its application in the hydroformylation reaction
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Paragraph 0077; 0078; 0079, (2017/11/08)
The invention relates to synthesis of first-class phosphorus functionalized polyether alkyl guanidinium ionic liquid, and an application of the first-class phosphorus functionalized polyether alkyl guanidinium ionic liquid in a homogeneous catalytic reaction. The functionalized ionic liquid of such class can be easily prepared by an ion exchange reaction between the polyether alkyl guanidinium ionic liquid and sulfonic acid type water soluble phosphine ligand. The designed phosphorus functionalized ionic liquid can be applied to organic reactions, including hydroformylation, hydroesterification, hydrocarboxylation and catalytic hydrogenation under the catalyzing of a transition metal; the dosage of the ionic liquid used in the catalytic reaction can be decreased; the activity of the catalytic reaction can be improved; a catalyst can be separated and cycled simply and conveniently.
METHOD FOR PRODUCING OXIDE
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Paragraph 0137-0139, (2016/06/28)
Provided is a method of oxidizing a substrate with excellent oxidizing power to yield a corresponding oxide. The method can employ a commercially available imide compound as intact as a catalyst and can produce the oxide in a high yield under mild conditions. A method for producing an oxide according to the present invention includes performing oxidation of a substrate in the presence of oxygen and ozone under catalysis of an imide compound to yield a corresponding oxide. The imide compound has a cyclic imide skeleton represented by Formula (I). In the formula, n is selected from 0 and 1; and X is selected from an oxygen atom and an —OR group, where R is selected from hydrogen and a hydroxy-protecting group.
Tsuji-Wacker Oxidation of Terminal Olefins using a Palladium-Carbon Nanotube Nanohybrid
Donck, Simon,Gravel, Edmond,Shah, Nimesh,Jawale, Dhanaji V.,Doris, Eric,Namboothiri, Irishi N. N.
, p. 2318 - 2322 (2015/08/11)
Palladium nanoparticles supported on carbon nanotubes were used in the Tsuji-Wacker oxidation. The palladium-based nanohybrid was found to be very active in combination with cuprous chloride for the selective oxidation of terminal olefins into methyl ketones. The co-catalytic system operates under very mild and sustainable conditions (room temperature, atmospheric pressure, low catalyst loading), as opposed to previously reported catalysts, and can be recycled without any loss in activity. Give it a whack: Palladium nanoparticles supported on carbon nanotubes are used in combination with cuprous chloride for the selective Tsuji-Wacker oxidation of terminal olefins into methyl ketones. The co-catalytic system operates under very mild and sustainable conditions and can be recycled without any loss in activity.
