937-61-1Relevant academic research and scientific papers
Selective alkene hydrogenation with atomic hydrogen permeating through a Pd sheet electrode
Maki,Harada,Hirano,Niwa,Yoshida,Ogata,Nakamatsu,Inoue,Iwakura
, p. 3575 - 3583 (2000)
Chemoselective hydrogenation of olefinic double bonds without concomitant hydrogenolysis of allylic and benzylic C-O linkages was performed successfully by the aid of active hydrogen permeated through a Pd sheet electrode.
Ambient Hydrogenation and Deuteration of Alkenes Using a Nanostructured Ni-Core–Shell Catalyst
Beller, Matthias,Feng, Lu,Gao, Jie,Jackstell, Ralf,Jagadeesh, Rajenahally V.,Liu, Yuefeng,Ma, Rui
supporting information, p. 18591 - 18598 (2021/06/28)
A general protocol for the selective hydrogenation and deuteration of a variety of alkenes is presented. Key to success for these reactions is the use of a specific nickel-graphitic shell-based core–shell-structured catalyst, which is conveniently prepared by impregnation and subsequent calcination of nickel nitrate on carbon at 450 °C under argon. Applying this nanostructured catalyst, both terminal and internal alkenes, which are of industrial and commercial importance, were selectively hydrogenated and deuterated at ambient conditions (room temperature, using 1 bar hydrogen or 1 bar deuterium), giving access to the corresponding alkanes and deuterium-labeled alkanes in good to excellent yields. The synthetic utility and practicability of this Ni-based hydrogenation protocol is demonstrated by gram-scale reactions as well as efficient catalyst recycling experiments.
Method for hydrogenolysis of halides
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Paragraph 0232; 0281-0283, (2021/01/11)
The invention discloses a method for hydrogenolysis of halides. The invention discloses a preparation method of a compound represented by a formula I. The preparation method comprises the following step: in a polar aprotic solvent, zinc, H2O and a compound represented by a formula II are subjected to a reaction as shown in the specification, wherein X is halogen; Y is -CHRR or R; hydrogenin H2O exists in the form of natural abundance or non-natural abundance. According to the preparation method, halide hydrogenolysis can be simply, conveniently and efficiently achieved through a simple and mild reaction system, and good functional group compatibility and substrate universality are achieved.
Photo-triggered hydrogen atom transfer from an iridium hydride complex to unactivated olefins
Guo, Xingwei,Pfund, Bj?rn,Schreier, Mirjam R.,Wenger, Oliver S.
, p. 8582 - 8594 (2020/09/07)
Many photoactive metal complexes can act as electron donors or acceptors upon photoexcitation, but hydrogen atom transfer (HAT) reactivity is rare. We discovered that a typical representative of a widely used class of iridium hydride complexes acts as an H-atom donor to unactivated olefins upon irradiation at 470 nm in the presence of tertiary alkyl amines as sacrificial electron and proton sources. The catalytic hydrogenation of simple olefins served as a test ground to establish this new photo-reactivity of iridium hydrides. Substrates that are very difficult to activate by photoinduced electron transfer were readily hydrogenated, and structure-reactivity relationships established with 12 different olefins are in line with typical HAT reactivity, reflecting the relative stabilities of radical intermediates formed by HAT. Radical clock, H/D isotope labeling, and transient absorption experiments provide further mechanistic insight and corroborate the interpretation of the overall reactivity in terms of photo-triggered hydrogen atom transfer (photo-HAT). The catalytically active species is identified as an Ir(ii) hydride with an IrII-H bond dissociation free energy around 44 kcal mol-1, which is formed after reductive 3MLCT excited-state quenching of the corresponding Ir(iii) hydride, i.e. the actual HAT step occurs on the ground-state potential energy surface. The photo-HAT reactivity presented here represents a conceptually novel approach to photocatalysis with metal complexes, which is fundamentally different from the many prior studies relying on photoinduced electron transfer. This journal is
Dehalogenative Deuteration of Unactivated Alkyl Halides Using D2O as the Deuterium Source
Xia, Aiyou,Xie, Xin,Hu, Xiaoping,Xu, Wei,Liu, Yuanhong
, p. 13841 - 13857 (2019/10/17)
The general dehalogenation of alkyl halides with zinc using D2O or H2O as a deuterium or hydrogen donor has been developed. The method provides an efficient and economic protocol for deuterium-labeled derivatives with a wide substrate scope under mild reaction conditions. Mechanistic studies indicated that a radical process is involved for the formation of organozinc intermediates. The facile hydrolysis of the organozinc intermediates provides the driving force for this transformation.
Synthesis of Benzyl Alkyl Ethers by Intermolecular Dehydration of Benzyl Alcohol with Aliphatic Alcohols under the Effect of Copper Containing Catalysts
Bayguzina,Gimaletdinova,Khusnutdinov
, p. 1148 - 1155 (2018/10/24)
Synthesis of benzyl alkyl ethers was performed in high yields by intermolecular dehydration of benzyl and primary, secondary, tertiary alcohols under the effect of copper containing catalysts. The formation of benzyl alkyl ethers occurs with participation of benzyl cation.
Inexpensive and rapid hydrogenation catalyst from CuSO4/CoCl2 — Chemoselective reduction of alkenes and alkynes in the presence of benzyl protecting groups
Ficker, Mario,Svenningsen, S?ren W.,Larribeau, Thomas,Christensen, J?rn B.
supporting information, p. 1125 - 1129 (2018/02/21)
The simple reduction of a number of alkenes and alkynes was performed with a typical reaction time of 20 min using a copper-cobalt catalytic system. The reduction did not cleave benzyl protecting groups which are usually vulnerable to catalytic hydrogenation reactions. The catalyst can be prepared in situ by reduction of the inexpensive precursor salts CuSO4 and CoCl2 with NaBH4. Sodium borohydride was also used as an easily handled hydrogen source for the catalytic reductions. No pressure, heating or inert atmosphere is required and purification/catalyst removal is achieved using extraction procedures, making this approach simple and efficient.
Visible-Light Photocatalyzed Deoxygenation of N-Heterocyclic N-Oxides
Kim, Kyu Dong,Lee, Jun Hee
supporting information, p. 7712 - 7716 (2019/01/03)
A scalable and operationally simple method is described that allows for the chemoselective deoxygenation of a wide range of N-heterocyclic N-oxides (a total of 36 examples). This visible-light-induced protocol features the use of only commercially available reagents, room-temperature conditions, and unprecedented chemoselective removal of the oxygen atom in a quinoline N-oxide in the presence of a pyridine N-oxide in the same molecule through the judicious selection of a photocatalyst.
Cobalt-Catalyzed Ligand-Controlled Regioselective Hydroboration/Cyclization of 1,6-Enynes
Xi, Tuo,Lu, Zhan
, p. 1181 - 1185 (2017/08/09)
A ligand-controlled cobalt-catalyzed regioselective hydroboration/cyclization of 1,6-enynes with HBPin was developed by switching the size of the coordinated side arm to afford alkenylboronates and alkylboronates, respectively. Gram-scale reactions could be easily conducted, which is beneficial for further derivatizations. A primary mechanism was proposed on the basis of substrate-controlled experiments and deuterium experiments.
Symbiotic Transition-Metal and Organocatalysis for Catalytic Ambient Amine Oxidation and Alkene Reduction Reactions
Murray, Alexander T.,King, Rose,Donnelly, Joseph V. G.,Dowley, Myles J. H.,Tuna, Floriana,Sells, Daniel,John, Matthew P.,Carbery, David R.
, p. 510 - 514 (2016/02/20)
A new oxidation reaction based on two simple catalysts, namely, alloxan and a CuI salt, is highly effective for the aerobic oxidation and oxidative cross-coupling of amines. The reaction is operationally simple, reaction atmospheres enriched in dioxygen are obviated, and neither catalyst component requires prior synthesis. Mechanistic investigations have been performed and point towards a complex reaction manifold with evidence that supports a catalytic cycle that does not proceed through a quinone-imine step. Additionally, this dual catalyst system is efficient to effect diimide-mediated hydrogenation reactions of alkenes and alkynes, a transformation that has not been reported previously in the context of quinone catalyst systems.
