106-88-7Relevant articles and documents
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Cvetanovic
, (1958)
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Jarvie,Cvetanovic
, p. 529 (1959)
Synthesis, crystal structure, and catalytic property of a vanadium(V) complex with mixed ligands
Shen,Zhang,Shao,Lian,Liu
, p. 372 - 375 (2015)
With a tridentate hydrazone ligand N′-(3-bromo-2-hydroxybenzylidene)-2-methylbenzohy-drazide (H2L) and a bidentate ligand benzohydroxamic acid (HL′) with VO(Acac)2, a mononuclear vanadium(V) complex was prepared and characterized by elemental analysis, IR spectroscopy and X-ray structure determination (CIF file CCDC no. 1029909). The complex crystallizes in the monoclinic space group C2/c with unit cell dimensions a = 27.870(2), b = 11.4893(5), c = 18.467(2) ?, β = 131.444(1)°, V = 4432.6(6) ?3, Z = 8, R 1 = 0.0350, and wR 2 = 0.0749. Single crystal X-ray diffraction analysis reveals that the V atom is coordinated by the phenolate O, imino N and enolate O atoms of the hydrazone ligand, and the carbonyl O and hydroxy O atoms of benzohydroxamate ligand, and one oxo O group, in an octahedral coordination. Catalytic oxidation of the complex on some olefins was performed.
Role of Recrystallization in Alkaline Treatment on the Catalytic Activity of 1-Butene Epoxidation
Zuo, Yi,Yang, Liqian,Jiang, Xiao,Ma, Mengtong,Wang, Yanli,Liu, Min,Song, Chunshan,Guo, Xinwen
, p. 6196 - 6204 (2020)
Two alkylol amines, which were ethanolamine (EOA) and triethanolamine (TEOA), were used to posttreat nanosized titanium silicalite-1 (TS-1) to improve its catalytic activity for 1-butene epoxidation. Comparative studies were conducted to clarify the influences of the EOA and TEOA concentrations on the physicochemical properties through detailed characterization. EOA treatment can dissolve the framework Si, [SiO4], on the external surface of TS-1, generating some macropores. TEOA serves as structure-directing agent to form MFI topology other than the dissolution of [SiO4], and promotes the recrystallization of [SiO4], forming new TS-1 particles over the external surface. The two treatments can both improve the catalytic activity of 1-butene epoxidation, but the samples treated with TEOA exhibit better catalytic stability. This can be attributed to the characteristic recrystallization of [SiO4] in the case of TEOA treatment, stabilizing the structure of TS-1 and maintaining more framework Ti and intercrystal space.
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Bottini,A.T. et al.
, p. 156 - 158 (1963)
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Synthesis, crystal structure and catalytic property of a dinuclear cobalt(III) complex derived from 2-ethyl-2-{[1-(2-hydroxy-5-methylphenyl)methylidene]amino}propane-1,3-diol
Qiu, Xiao-Yang
, p. 182 - 186 (2018)
With a tetradentate Schiff base ligand 2-ethyl-2-{[1-(2-hydroxy-5-methylphenyl)methylidene]amino}propane-1,3-diol (H3L) with cobalt nitrate and ammonium thiocyanate, a dinuclear cobalt(III) complex was prepared and characterized by elemental analysis, IR spectroscopy and X-ray structure determination. The complex crystallizes in the monoclinic space group P21/n with unit cell dimensions a = 17.682(2) ?, b = 22.652(2) ?, c = 18.617(2) ?, β = 99.546(2)°, V = 7,353.5(12) ?3, Z = 4, R1 = 0.0956, and wR2 = 0.2027. Single crystal X-ray diffraction analysis reveals that the asymmetric unit of the compound contains two dinuclear cobalt(III) complex molecules, three methanol molecules and one water molecule of crystallization. The Co???Co distances in the dinuclear cobalt(III) complex molecules are about 2.97 ?. The Co atoms are in octahedral coordination. The complex has effective property on the oxidation of various aliphatic and aromatic olefins.
Structural and dynamical aspects of alkylammonium salts of a silicodecatungstate as heterogeneous epoxidation catalysts
Uchida, Sayaka,Kamata, Keigo,Ogasawara, Yoshiyuki,Fujita, Megumi,Mizuno, Noritaka
, p. 9979 - 9983 (2012)
The structural and dynamical aspects of alkylammonium salts of a silicodecatungstate [(CH3)4N]4[γ-SiW 10O34(H2O)2] [C1], [(n-C 3H7)4N]4[γ-SiW 10O34(H2O)2] [C3], [(n-C 4H9)4N]4[γ-SiW 10O34(H2O)2] [C4], and [(n-C 5H11)4N]4[γ-SiW 10O34(H2O)2] [C5] were investigated. The results of sorption isotherms, XRD analyses, and solid-state NMR spectroscopy show that facile sorption of solvent molecules, flexibility of structures, and high mobility of alkylammonium cations are crucial to the uniform distribution of reactant and oxidant molecules throughout the bulk solid, which are related to the high catalytic activities for epoxidation of alkenes.
Liquid- and vapor-phase hydrogenation of 1-epoxy-3-butene using self-assembled monolayer coated palladium and platinum catalysts
Kahsar, Karl R.,Schwartz, Daniel K.,Medlin, J. Will
, p. 102 - 106 (2012)
Alkanethiol self-assembled monolayers (SAMs) have recently been shown to be effective catalyst modifiers for increasing the selectivity of the hydrogenation of 1-epoxy-3-butene (EpB) to 1-epoxybutane in the gas phase. In the results reported here, we demonstrate that SAM coatings can similarly be applied to other supported metals (Pt) and in liquid-phase reaction environments. Coating a Pt/Al2O3 catalyst with n-octadecanethiol resulted in a large improvement in selectivity during vapor-phase EpB hydrogenation, similar to that observed for supported Pd. The liquid phase hydrogenation of EpB using SAM-coated catalysts showed similar selectivity trends in some cases, but interactions of the solvent with the SAM were also important in controlling selectivity. In particular, using a heptane solvent, epoxybutane selectivity increased from 36% with an uncoated Pd/Al 2O3 catalyst to 74% with a thioglycerol SAM-coated catalyst. SAM quality was shown to have a strong impact on the rate of reaction but little effect on selectivity. The results generally indicated that selectivity modification with thiol SAMs is extendable to other supported metals and a variety of reaction environments.
Phosphotungstic acid supported on magnetic nanoparticles as an efficient reusable catalyst for epoxidation of alkenes
Kooti,Afshari
, p. 3473 - 3478 (2012)
A new magnetically separable catalyst consisting of phosphotungstic acid supported on imidazole functionalized silica coated cobalt ferrite nanoparticles was prepared. The synthesized catalyst was characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), thermogravimetric analysis (TGA), Fourier transform infrared (FT-IR), and inductively coupled plasma atomic emission spectroscopy (ICP-AES). This immobilized phosphotungstic acid was shown to be an efficient heterogeneous catalyst for the epoxidation of various alkenes using tert-butylhydroperoxide (t-BuOOH) as oxidant. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no significant loss of catalytic activity.
Tris-imidazolinium-based porous poly(ionic liquid)s as an efficient catalyst for decarboxylation of cyclic carbonate to epoxide
Li, Yang,Wang, Liguo,Cao, Yan,Xu, Shuang,He, Peng,Li, Huiquan,Liu, Hui
, p. 14193 - 14202 (2021/04/22)
A series of imidazolinium-based porous poly(ionic liquid)s (PILs) with different anions prepared by free-radical copolymerization of an arene-bridged tris-vinylimidazolium salt and divinylbenzene (DVB) were constructed. The as-prepared PILs were characterized by BET, SEM, TEM, TGA and Elemental Analysis (EA), and the results showed that they had plentiful ionic sites, and abundant and stable mesopores. In particular, the density of ionic sites and pore structure of PILs could be controlled by adjusting the content of DVB. Moreover, the PILs were used as efficient heterogeneous catalysts for the decarboxylation of cyclic carbonates to epoxides for the first time. Results showed that the catalytic activity of PILs was positively correlated with the nucleophilicity of the anions in PILs, and PDVB-[PhTVIM]Cl-1 with a chloride anion-enriched skeleton displayed the best catalytic performance. Without any solvent or cocatalyst, PDVB-[PhTVIM]Cl-1 achieved a TOF value of 108.1 h-1and the yield of butylene oxide of 89.6%, which was even better than the homogeneous IL-based catalysts (TOF value: 8.7 h-1) that had been previously reported. Meanwhile, PDVB-[PhTVIM]Cl-1 also exhibited excellent recyclability and substrate compatibility.
Synthesis, crystal structures and catalytic activity of oxidovanadium(V) complexes with tridentate ONO aroylhydrazone ligands
Liang, Min,Zou, Dong-Hui,Chen, Wei,Kan, Wei,Tian, Zhi-Ming
, (2021/03/22)
Two oxidovanadium(V) complexes, [VOL1(OEt)] (1) and [V2O2(L2)2(OEt)2] (2), where L1 and L2 are the anions of 2-amino-N′-(2-hydroxybenzylidene)benzohydrazide (H2L1) and N′-(2-hydroxybenzylidene)-4-hydroxybenzohydrazide (H2L2), respectively, have been synthesized and characterized by elemental analysis, infrared and electronic spectra, and 1H NMR spectra. Structures of the complexes were further confirmed by single-crystal X-ray determination. The V atom in the mononuclear complex 1 is in square pyramidal coordination, and those in the dinuclear complex 2 are in octahedral coordination. Both aroylhydrazone ligands coordinate to the V atoms through the phenolate O, imino N, and enolate O atoms. The ethanol ligand in complex 1 is in terminal coordination mode, while that in complex 2 is in bridging coordination mode. The complexes function as effective olefin epoxidation catalysts with hydrogen peroxide as terminal oxidant and sodium hydrogen carbonate as a co-catalyst.
Method for epoxidizing small-molecular olefin
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Paragraph 0172-0173; 0200-0215; 0217-0232, (2021/06/06)
The invention relates to a micromolecular olefin epoxidation method, which is characterized by comprising the following steps: contacting micromolecular olefin, an organic peroxide and a titanium-silicon composite oxide under epoxidation reaction conditions of at least two reaction temperatures of A and B to obtain an alkylene oxide-containing product, wherein the A is 80-95 DEG C, the B is 100-120 DEG C, the titanium-silicon composite oxide is of an amorphous structure, is formed by aggregation of nano-particles and has mesopores in the range of 16-50 nm, the ratio of the volume of the mesopores to the total pore volume is larger than or equal to 80%, and the volume of the mesopores is larger than or equal to 0.5 cm/g. According to the method, the amorphous titanium-silicon-titanium-silicon composite oxide is taken as the catalyst, and at least two sections of conditions with different reaction temperatures are combined, so that compared with the prior art, the catalyst is stable in structure, low in cost, high in olefin epoxidation reaction activity and good in product selectivity.
