4829-01-0Relevant articles and documents
Organocatalytic epoxidation and allylic oxidation of alkenes by molecular oxygen
Orfanidou, Maria,Petsi, Marina,Zografos, Alexandros L.
supporting information, p. 9172 - 9178 (2021/11/30)
Pyrrole-proline diketopiperazine (DKP) acts as an efficient mediator for the reduction of dioxygen by Hantzsch ester under mild conditions to allow the aerobic metal-free epoxidation of electron-rich alkenes. Mechanistic crossovers are underlined, explaining the dual role of Hantzsch ester as a reductant/promoter of the DKP catalyst and a simultaneous competitor for the epoxidation of alkenes when HFIP is used as a solvent. Expansion of this protocol to the synthesis of allylic alcohols was achieved by adding a catalytic amount of selenium dioxide as an additive, revealing a superior method to the classical application of t-BuOOH as a selenium dioxide oxidant.
RUTHENIUM COMPLEX AND PRODUCTION METHOD THEREOF, CATALYST, AND PRODUCTION METHOD OF OXYGEN-CONTAINING COMPOUND
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Paragraph 0113-0117, (2021/01/29)
PROBLEM TO BE SOLVED: To provide a ruthenium complex that is particularly useful as a catalyst for oxidizing a substrate having a carbon-hydrogen bond. SOLUTION: The ruthenium complex represented by the general formula (i) or a cis conformer thereof is provided. In the general formula (i), R1 represents H, a phenyl group or a substituted phenyl group; R2 represents H, a phenyl group or an alkyl group; L1 represents halogen or water molecule; L2 represents triphenylphosphine, pyridine, imidazole or dimethylsulfoxide; X represents halogen; and n represents 1 or 2. SELECTED DRAWING: None COPYRIGHT: (C)2021,JPO&INPIT
Aldehyde-catalyzed epoxidation of unactivated alkenes with aqueous hydrogen peroxide
Kokotos, Christoforos G.,Kokotou, Maroula G.,Lotter, Dominik,Sparr, Christof,Triandafillidi, Ierasia
, p. 10191 - 10196 (2021/08/12)
The organocatalytic epoxidation of unactivated alkenes using aqueous hydrogen peroxide provides various indispensable products and intermediates in a sustainable manner. While formyl functionalities typically undergo irreversible oxidations when activating an oxidant, an atropisomeric two-axis aldehyde capable of catalytic turnover was identified for high-yielding epoxidations of cyclic and acyclic alkenes. The relative configuration of the stereogenic axes of the catalyst and the resulting proximity of the aldehyde and backbone residues resulted in high catalytic efficiencies. Mechanistic studies support a non-radical alkene oxidation by an aldehyde-derived dioxirane intermediate generated from hydrogen peroxide through the Payne and Criegee intermediates.
Lamellar porous mo-modified carbon nitride polymers photocatalytic epoxidation of olefins
Gu, Qian,Jiang, Ping Ping,Shen, Yirui,Zhang, Kai,Wai, Phyu Thin,Haryono, Agus
, (2021/02/21)
A lamellar porous Mo-modified carbon nitride polymers (CN-Mo) was successfully prepared by a simple bottom-up method, which involves molecule self-assembly by hydrogen bonding between uracil and melamine. Analysis Results of X-ray diffraction (XRD), scann
Construction of an Asymmetric Porphyrinic Zirconium Metal-Organic Framework through Ionic Postchiral Modification
Berijani, Kayhaneh,Morsali, Ali
, p. 206 - 218 (2021/01/11)
Herein, one kind of neutral chiral zirconium metal-organic framework (Zr-MOF) was reported from the porphyrinic MOF (PMOF) family with a metallolinker (MnIII-porphyrin) as the achiral polytopic linker [free base tetrakis(4-carboxyphenyl)porphyrin] and chiral anions. Achiral Zr-MOF was chiralized through the exchange of primitive anions with new chiral organic anions (postsynthetic exchange). This chiral functional porphyrinic MOF (CPMOF) was characterized by several techniques such as powder X-ray diffraction, Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, 1H NMR, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and Brunauer-Emmett-Teller measurements. In the resulting structure, there are two active metal sites as Lewis acid centers (Zr and Mn) and chiral species as Br?nsted acid sites along with their cooperation as nucleophiles. This CPMOF shows considerable bimodal porosity with high surface area and stability. Additionally, its ability was investigated in asymmetric catalyses of prochiral substrates. Interactions between framework chiral species and prochiral substrates have large impacts on the catalytic ability and chirality induction. This chiral catalyst proceeded asymmetric epoxidation and CO2 fixation reactions at lower pressure with high enantioselectivity due to Lewis acids and chiral auxiliary nucleophiles without significant loss of activity up to the sixth step of consecutive cycles of reusability. Observations revealed that chiralization of Zr-MOF could happen by a succinct strategy that can be a convenient method to design chiral MOFs.
A new and efficient methodology for olefin epoxidation catalyzed by supported cobalt nanoparticles
Rossi-Fernández, Lucía,Dorn, Viviana,Radivoy, Gabriel
supporting information, p. 519 - 526 (2021/03/31)
A new heterogeneous catalytic system consisting of cobalt nanoparticles (CoNPs) supported on MgO and tert-butyl hydroperoxide (TBHP) as oxidant is presented. This CoNPs@MgO/t-BuOOH catalytic combination allowed the epoxidation of a variety of olefins with good to excellent yield and high selectivity. The catalyst preparation is simple and straightforward from commercially available starting materials and it could be recovered and reused maintaining its unaltered high activity.
Method for synthesizing epoxy compound by catalyzing epoxidation of olefin with nano-alumina
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Paragraph 0038-0079, (2020/06/17)
The invention belongs to the field of organic synthesis and catalysis, and discloses a method for synthesizing an epoxy compound by catalyzing epoxidation of olefin with nano-alumina. The method comprises the following steps: adding a solvent, olefin, nano-alumina and fatty aldehyde into a reactor to obtain a mixed solution, vacuumizing a reaction container, introducing oxygen, heating and stirring for a reaction by taking olefin as a raw material, taking nano-alumina as a catalyst and taking fatty aldehyde as a reducing agent, obtaining a reaction solution after the reaction is finished, andseparating and purifying the reaction solution to obtain the epoxy compound. The method has the advantages of cheap and easily available in the catalyst, easy to obtain, mild in reaction condition, wide in substrate applicability and safe and simple to operate, and has a potential industrial application prospect.
Epoxidation of Alkenes with Molecular Oxygen as the Oxidant in the Presence of Nano-Al 2O 3
Zhou, Xuan,Wang, Qiong,Xiong, Wenfang,Wang, Lu,Ye, Rongkai,Xiang, Ge,Qi, Chaorong,Hu, Jianqiang
, p. 1789 - 1794 (2020/09/18)
The nano-Al 2O 3-promoted epoxidation of alkenes with molecular oxygen as the oxidant has been developed, providing an efficient route to a variety of epoxides in moderate to excellent yields. The environmentally friendly and efficient nano-Al 2O 3catalyst could be easily recovered and reused five times without significant loss of activity.
Method for catalyzing epoxidation of olefin
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Paragraph 0037-0038, (2020/04/17)
The invention discloses a method for catalyzing epoxidation of olefin. According to the method, an olefin compound is used as a raw material, hydrogen peroxide, peracetic acid, tert-butyl hydroperoxide and m-chloroperoxybenzoic acid are used as oxidants, a metalloporphyrin-based super-cross-linked polymer is used as a catalyst, and a catalytic reaction is carried out at a reaction temperature of 25-80 DEG C to obtain an epoxide at high selectivity. The method has the advantages of simple process, high yield, catalyst recyclability, mild conditions and the like.
One-pot synthesis of oxazolidinones and five-membered cyclic carbonates from epoxides and chlorosulfonyl isocyanate: Theoretical evidence for an asynchronous concerted pathway
Demir, Esra,Sari, Ozlem,?etinkaya, Yasin,Atmaca, Ufuk,Erdem, Safiye Sa?,?elik, Murat
supporting information, p. 1805 - 1819 (2020/11/07)
The one-pot reaction of chlorosulfonyl isocyanate (CSI) with epoxides having phenyl, benzyl and fused cyclic alkyl groups in different solvents under mild reaction conditions without additives and catalysts was studied. Oxazolidinones and five-membered cyclic carbonates were obtained in ratios close to 1:1 in the cyclization reactions. The best yields of these compounds were obtained in dichloromethane (DCM). Together with 16 known compounds, two novel oxazolidinone derivatives and two novel cyclic carbonates were synthesized with an efficient and straightforward method. Compared to the existing methods, the synthetic approach presented here provides the following distinct advantageous: being a one-pot reaction with metal-free reagent, having shorter reaction times, good yields and a very simple purification method. Moreover, using the density functional theory (DFT) method at the M06-2X/6-31+G(d,p) level of theory the mechanism of the cycloaddition reactions has been elucidated. The further investigation of the potential energy surfaces associated with two possible channels leading to oxazolidinones and five-membered cyclic carbonates disclosed that the cycloaddition reaction proceeds via an asynchronous concerted mechanism in gas phase and in DCM.
