1728-25-2Relevant articles and documents
Phosphorus-doped macroporous carbon spheres for high efficiency selective oxidation of cyclooctene by air
Li, Chuanxi,Yang, Manman,Liu, Ruihua,Zhao, Fangfang,Huang, Hui,Liu, Yang,Kang, Zhenhui
, p. 22419 - 22424 (2014)
The phosphorus-doped macroporous carbon spheres (PMCS) with a high specific surface area (574.68 m2 g-1) were synthesized by a template method. A series of catalytic experiments showed that the PMCS possessed excellent catalytic ability for the selective oxidation of cyclooctene (conversion based on cyclooctene was 50.69% and the selectivity to epoxycyclooctane was 88.47%). This journal is the Partner Organisations 2014.
Comparison between various Keggin and Wells-Dawson sandwich-type polyoxometalates in catalytic oxidation of cyclooctene and cyclohexene with hydrogen peroxide
Farsani, Mostafa Riahi,Jalilian, Fariba,Yadollahi, Bahram,Rudbari, Hadi Amiri
, p. 7 - 11 (2015)
The catalytic performance of tetra-n-butylammonium salts of Keggin and Wells-Dawson sandwich-type polyoxotungstates, [M4 (PW9O34)2]m- and [M4(P2W15O56)2]n- (M = Mn2+, Fe3+, Co2+, Ni2+, Zn2+), in the oxidation of cyclooctene and cyclohexene with 30% hydrogen peroxide under various conditions was investigated. In comparison, Wells-Dawson sandwich-type polyoxometalates were found to be less active than Keggin ones. In both of them, those containing Zn and Fe gave higher conversions for different oxidation conditions. These catalysts showed very good reusability in the oxidation reaction.
A nickel-modified polyoxometalate towards a highly efficient catalyst for selective oxidation of hydrocarbons
Zhou, Lei,Liu, Juan,Ji, Wenbin,Huang, Hui,Hu, Hailiang,Liu, Yang,Kang, Zhenhui
, p. 12686 - 12691 (2014)
A nickel-modified polyoxometalate compound was synthesized which exhibited excellent catalytic activity (conversion: 41.63%; selectivity: 97.21%) for selective oxidation of cyclooctene using air as an oxidant without a solvent.
Solvent-free selective epoxidation of cyclooctene using supported gold catalysts
Bawaked, Salem,Dummer, Nicholas F.,Dimitratos, Nikolaos,Bethell, Donald,He, Qian,Kiely, Christopher J.,Hutchings, Graham J.
, p. 1037 - 1044 (2009)
Oxidation is one of the major pathways for the synthesis of chemical intermediates. The epoxidation of alkenes by the electrophilic addition of oxygen to a carbon-carbon double bond remains one of the most significant challenges in oxidation. Of key impor
Mesostructured dihydroxy-functionalized guanidinium-based polyoxometalate with enhanced heterogeneous catalytic activity in epoxidation
Chen, Guojian,Zhou, Yu,Zhao, Pingping,Long, Zhouyang,Wang, Jun
, p. 561 - 569 (2013)
A mesostructured ionic liquid-polyoxometalate (IL-POM) hybrid has been prepared through designing a new dihydroxy-tethered guanidinium-based IL, N′′-(2,3-dihydroxypropyl)-N,N,N′,N′- tetramethylguanidinium chloride, to interact with Keggin-type POM phosphotungstic acid (H3PW) in a self-assembly process. Scanning electron microscopy and transmission electron microscopy showed its special coral-shaped micromorphology. Nitrogen sorption analysis indicated the formation of a porous structure with a moderate surface area of about 30 m2 g-1 and narrowly distributed pore size located in the mesoscale. Assessed in the cis-cyclooctene epoxidation with H2O2, the mesostructured hybrid exhibited superior heterogeneous catalytic activity and steady reusability, and the conversion was more than four times that of homogeneous H3PW itself, and more than 14 times that of the nonporous analogues. On the basis of the experimental results, a unique substrate-solvent-catalyst synergistic mechanism is proposed and discussed for understanding the dramatically enhanced catalytic performance. Copyright
Coordinate-polymerized organic ligand towards an efficient catalyst for selective hydrocarbon oxidation
Li, Kaixuan,Hu, Hailiang,Liu, Beibei,Lin, Xiaoling,Huang, Hui,Liu, Yang,Kang, Zhenhui
, p. 63940 - 63945 (2016)
Here we show catalyst design based on an isoxazole derivative via a coordinate-polymerized strategy. Three new coordination polymers, [Co(bpp)(mpca)2] (1), [Zn(bpp)(mpca)2] (2), and [Cd(bpp)(mpca)2] (3) [bpp = 1,3-bis(4-pyridyl)propane, mpca = 5-methyl-3-phenylisoxazole-4-carboxylic acid], have been synthesized under hydrothermal conditions. Single crystal X-ray diffraction analysis reveals that, compounds 1-3 exhibit similar wave-like chains, with mpca functioning as pendant phenyl-isoxazole arms. Catalytic experiments show that all three compounds can be used as efficient heterogeneous catalysts for the selective oxidation of cyclooctene.
Synthesis of a pair of homochiral manganese-based coordination polymers as stable catalyst for the selective oxidation of cis-cyclooctene
Zhang, Guangju,Shi, Yang,Wei, Ying,Zhang, Qingguo,Zhang, Yanping,Cai, Kedi,Xiu, Siqi
, p. 81 - 84 (2018)
A pair of homochiral manganese-based coordination polymers [Mn(H2O)2(bpy)(L-DBTA)] (L-1) and [Mn(H2O)2(bpy)(D-DBTA)](D-1): Syntheses, crystal structures and catalytic properties for the selective oxidation of cis-cyclooctene. The homochiral manganese-based 3D supermolecule framework exhibits high catalytic activity (38.85% conversion based on cis-cyclooctene and 76.13% selectivity for epoxycyclooctane) and stability for selective oxidation of cis-cyclooctene in the absence of solvent using TBHP as radical initiator and oxygen (in the air) as oxidant at 80 °C.
Complexation of crystal-like mesoporous phenylene-silica with Cr(CO) 3 and catalytic performance in the oxidation of cyclooctene
Coelho, Ana C.,Balula, Salete S.,Antunes, Margarida M.,Gerganova, Tsvetelina I.,Bion, Nicolas,Ferreira, Paula,Pillinger, Martyn,Valente, Anabela A.,Rocha, Jo?o,Gonalves, Isabel S.
, p. 13 - 18 (2010)
Chromium carbonyl complexes were incorporated into a molecularly ordered mesoporous phenylene-silica by reaction with Cr(CO)6 in refluxing 1,2-dichloroethane (DCE). The modified material with a chromium loading of 0.07 mmol g-1 was characterised by powder X-ray diffraction, N2 adsorption, thermogravimetric analysis (TGA), FT-IR, 13C and 29Si MAS NMR spectroscopies. TGA under air indicated that thermal decarbonylation between 250 and 350 °C preceded the Cr-promoted decomposition and release of organic fragments at a lower temperature (onset ca. 380 °C) than that registered for the phenylene-silica precursor (onset ca. 550 °C). The catalytic performance of the modified phenylene-silica was evaluated in the oxidation of cis-cyclooctene at 55 °C with tert-butylhydroperoxide (TBHP) as the oxidant and DCE as the co-solvent. The main product was the epoxide, formed in 83% yield after 24 h, with 2-cycloocten-1-one being the main by-product. Although the activity of the catalyst decreased after the first recycle, possibly due to partial chromium leaching, it remained nearly the same thereafter, and leaching tests indicated that the catalytic reaction was essentially heterogeneous in nature. Tests carried out using a radical scavenger indicated that the reaction of the olefin with TBHP may involve both free radical and non-radical reaction mechanisms.
Visible-Light-Enabled Allylic C-H Oxidation: Metal-free Photocatalytic Generation of Enones
Liu, Chao,Liu, Hui,Zheng, Xuan,Chen, Shanyi,Lai, Qihong,Zheng, Changlong,Huang, Mingqiang,Cai, Kaicong,Cai, Zhixiong,Cai, Shunyou
, p. 1375 - 1381 (2022/02/07)
A practical and efficient method has been established for the direct oxidation of allylic C-H bonds catalyzed by visible-light-enabled photoredox agents. This protocol uses oxygen as the sole oxidant under metal-free conditions at room temperature and pro
New Cu(II), Co(II) and Ni(II) azo-Schiff base complexes: Synthesis, characterization, catalytic oxidation of alkenes and DFT study
Lashanizadegan, Maryam,Asna Ashari, Hadiseh,Sarkheil, Marzieh,Anafcheh, Maryam,Jahangiry, Samira
, (2021/03/22)
Three new complexes with general formula of ML (M = Cu (1), Co (2), Ni (3)) containing an azo-Schiff base ligand (H2L) derived from 2,3-butanediamine and 4-(benzeneazo) salicylaldehyde were synthesized by template method. Characterization of the ligand and complexes were accomplished with FT-IR, UV–Vis, and 1H NMR. The catalytic activity of the complexes (1–3) were tested for the oxidation of various alkenes (cyclooctene, cyclohexene, styrene, α-methyl styrene, and norbornene) applying tert-butyl hydroperoxide (TBHP) as an oxidizing agent, and it was found that they were acceptable catalysts. Under the optimized reaction conditions, CuL complex displayed 94% conversion for the oxidation of cyclooctene, and CoL and NiL complexes exhibited 90 and 85% conversions for oxidizing α-methyl styrene, respectively. Based on our density functional computations, diffuse functions are compulsory in the basis set for geometry optimization of these systems. Therefore, the most stable structures and the vibrational frequencies were calculated at the M06-2X/6–311++G(d,p) level. By establishing the correlation between observed and calculated frequencies, the assignment of the vibrational modes was performed. Based on natural charge analysis (NAO), the back electron transfer from ML to the TBHP breaks the O–O bond and facilitates the formation of tert-butoxyl radicals.
