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1.
Mild and Selective Catalytic Hydrogenation of the C=C Bond in α,β‐Unsaturated Carbonyl Compounds Using Supported Palladium Nanoparticles 下载免费PDF全文
Dr. Anuja Nagendiran Vlad Pascanu Dr. Antonio Bermejo Gómez Greco González Miera Dr. Cheuk‐Wai Tai Dr. Oscar Verho Prof. Dr. Belén Martín‐Matute Prof. Dr. Jan‐E. Bäckvall 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):7184-7189
Chemoselective reduction of the C=C bond in a variety of α,β‐unsaturated carbonyl compounds using supported palladium nanoparticles is reported. Three different heterogeneous catalysts were compared using 1 atm of H2: 1) nano‐Pd on a metal–organic framework (MOF: Pd0‐MIL‐101‐NH2(Cr)), 2) nano‐Pd on a siliceous mesocellular foam (MCF: Pd0‐AmP‐MCF), and 3) commercially available palladium on carbon (Pd/C). Initial studies showed that the Pd@MOF and Pd@MCF nanocatalysts were superior in activity and selectivity compared to commercial Pd/C. Both Pd0‐MIL‐101‐NH2(Cr) and Pd0‐AmP‐MCF were capable of delivering the desired products in very short reaction times (10–90 min) with low loadings of Pd (0.5–1 mol %). Additionally, the two catalytic systems exhibited high recyclability and very low levels of metal leaching. 相似文献
2.
In this paper, a novel improvement in the catalytic Fenton reaction system named MHACF-NH2-MIL-101(Cr) was constructed based on H2 and Pd/NH2-MIL-101(Cr). The improved system would result in an accelerated reduction in FeIII, and provide a continuous and fast degradation efficiency of the 10 mg L-1 4-chlorophenol which was the model contaminant by using only trace level FeII. The activity of Pd/NH2-MIL-101(Cr) decreased from 100% to about 35% gradually during the six consecutive reaction cycles of 18 h. That could be attributed to the irreversible structural damage of NH2-MIL-101(Cr). 相似文献
3.
Jean‐Claude Daran Funda Demirhan
zgür Yldrm Bekir etinkaya 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(2):m48-m52
Owing to increasing interest in the use of N‐heterocyclic carbenes (NHCs) based on imidazolidinium ions as ligands in the design of highly efficient transition‐metal‐based homogeneous catalysts, the characterizations of the 1‐ferrocenylmethyl‐3‐(2,4,6‐trimethylbenzyl)imidazolidin‐3‐ium iodide salt, [Fe(C5H5)(C19H24N2)]I, (I), and the palladium complex trans‐bis(3‐benzyl‐1‐ferrocenylmethyl‐1H‐imidazolidin‐2‐ylidene)diiodidopalladium(II), [Fe2Pd(C5H5)2(C16H17N2)2I2], (II), are reported. Compound (I) has two iodide anions and two imidazolidinium cations within the asymmetric unit (Z′ = 2). The two cations have distinctly different conformations, with the ferrocene groups orientated exo and endo with respect to the N‐heterocyclic carbene. Weak C—H donor hydrogen bonds to both the iodide anions and the π system of the mesitylene group combine to form two‐dimensional layers perpendicular to the crystallographic c direction. Only one of the formally charged imidazolidinium rings forms a near‐linear hydrogen bond with an iodide anion. Complex (II) shows square‐planar coordination around the PdII metal, which is located on an inversion centre (Z′ = 0.5). The ferrocene and benzyl substituents are in a trans–anti arrangement. The Pd—C bond distance between the N‐heterocyclic carbene ligands and the metal atom is 2.036 (7) Å. A survey of related structures shows that the lengthening of the N—C bonds and the closure of the N—C—N angle seen here on metal complexation is typical of similar NHCs and their complexes. 相似文献
4.
Edward D. Cross Kristen L. MacDonald Robert McDonald Matthias Bierenstiel 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(1):23-27
The reaction of dichlorido(cod)palladium(II) (cod = 1,5‐cyclooctadiene) with 2‐(benzylsulfanyl)aniline followed by heating in N,N‐dimethylformamide (DMF) produces the linear trinuclear Pd3 complex bis(μ2‐1,3‐benzothiazole‐2‐thiolato)bis[μ2‐2‐(benzylsulfanyl)anilinido]dichloridotripalladium(II) N,N‐dimethylformamide disolvate, [Pd3(C7H4NS2)2(C13H12NS)2Cl2]·2C3H7NO. The molecule has symmetry and a Pd...Pd separation of 3.2012 (4) Å. The outer PdII atoms have a square‐planar geometry formed by an N,S‐chelating 2‐(benzylsulfanyl)anilinide ligand, a chloride ligand and the thiolate S atom of a bridging 1,3‐benzothiazole‐2‐thiolate ligand, while the central PdII core shows an all N‐coordinated square‐planar geometry. The geometry is perfectly planar within the PdN4 core and the N—Pd—N bond angles differ significantly [84.72 (15)° for the N atoms of ligands coordinated to the same outer Pd atom and 95.28 (15)° for the N atoms of ligands coordinated to different outer Pd atoms]. This trinuclear Pd3 complex is the first example of one in which 1,3‐benzothiazole‐2‐thiolate ligands are only N‐coordinated to one Pd centre. The 1,3‐benzothiazole‐2‐thiolate ligands were formed in situ from 2‐(benzylsulfanyl)aniline. 相似文献
5.
Adsorptive Separation of Acetylene from Light Hydrocarbons by Mesoporous Iron Trimesate MIL‐100(Fe) 下载免费PDF全文
Sukyung Lee Kyoung Ho Cho Dr. Young Kyu Hwang Prof. Dr. Marco Daturi Prof. Chul‐Ho Jun Prof. Dr. Rajamani Krishna Prof. Dr. Jong‐San Chang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(50):18431-18438
A reducible metal–organic framework (MOF), iron(III) trimesate, denoted as MIL‐100(Fe), was investigated for the separation and purification of methane/ethane/ethylene/acetylene and an acetylene/CO2 mixtures by using sorption isotherms, breakthrough experiments, ideal adsorbed solution theory (IAST) calculations, and IR spectroscopic analysis. The MIL‐100(Fe) showed high adsorption selectivity not only for acetylene and ethylene over methane and ethane, but also for acetylene over CO2. The separation and purification of acetylene over ethylene was also possible for MIL‐100(Fe) activated at 423 K. According to the data obtained from operando IR spectroscopy, the unsaturated FeIII sites and surface OH groups are mainly responsible for the successful separation of the acetylene/ethylene mixture, whereas the unsaturated FeII sites have a detrimental effect on both separation and purification. The potential of MIL‐100(Fe) for the separation of a mixture of C2H2/CO2 was also examined by using the IAST calculations and transient breakthrough simulations. Comparing the IAST selectivity calculations of C2H2/CO2 for four MOFs selected from the literature, the selectivity with MIL‐100(Fe) was higher than those of CuBTC, ZJU‐60a, and PCP‐33, but lower than that of HOF‐3. 相似文献
6.
Coordination Polymer Nanobamboos of {FexIn1−x}‐MIL‐88B: Induced Formation of a Virtual In‐MIL‐88B 下载免费PDF全文
Shin Ae Park Hee Jung Lee Yea Jin Cho Sora Choi Prof. Moonhyun Oh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(19):5559-5564
A precise fabrication of nanobamboo structures made from hybrid coordination polymers of the type {FexIn1?x}‐MIL‐88B is demonstrated. The compositions of the hybrid coordination polymer nanobamboos of {FexIn1?x}‐MIL‐88B (x=0.06, 0.19, or 0.75) are regulated by altering the amount of metal ions used in the reactions. Interestingly, the formation of a virtual In‐MIL‐88B (precise structure, {Fe0.06In0.94}‐MIL‐88B), which cannot be created in a typical reaction, is induced by the assistance of a Fe‐MIL‐88B structure. The a and c cell parameters of {Fe0.06In0.94}‐MIL‐88B are calculated at 10.95 and 19.86 Å, respectively. These values of {Fe0.06In0.94}‐MIL‐88B are larger than those of pure Fe‐MIL‐88B owing to the large ionic size of In3+ within the framework. 相似文献
7.
Nobuo Okabe Kana Hagihara Mamiko Odoko Yasunori Muranishi 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):m150-m152
In the title compounds, [Pd(C10H6O2)(C10H8N2)], (I), and [Pd(C10H6O2)(C18H12N2)], (II), each PdII atom has a similar distorted cis‐planar four‐coordination geometry involving two O atoms of the 2,3‐naphthalenediolate dianion and two N atoms of the 2,2′‐bipyridine or 2,2′‐biquinoline ligand. The overall structure of (I) is essentially planar, but that of (II) is not, as a result of intramolecular overcrowding leading to bowing of the biquinoline ligand. 相似文献
8.
Single‐Molecule Magnet Behavior of Individual Polyoxometalate Molecules Incorporated within Biopolymer or Metal–Organic Framework Matrices 下载免费PDF全文
Dr. Eric Rivière Shu Yang Dr. Catherine Roch‐Marchal Dr. Anne Dolbecq Dr. Corine Simonnet‐Jégat Prof. Nathalie Steunou Dr. Nathalie Leclerc‐Laronze Prof. Laurent Ruhlmann Prof. Talal Mallah Dr. Wolfgang Wernsdorfer Prof. Pierre Mialane 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(19):6564-6574
The chemically and structurally highly stable polyoxometalate (POM) single‐molecule magnet (SMM) [(FeW9O34)2Fe4(H2O)2]10? (Fe6W18) has been incorporated by direct or post‐synthetic approaches into a biopolymer gelatin (Gel) matrix and two crystalline metal–organic frameworks (MOFs), including one diamagnetic (UiO‐67) and one magnetic (MIL‐101(Cr)). Integrity of the POM in the Fe6W18@Gel, Fe6W18@UiO‐67 and Fe6W18@MIL‐101(Cr) composites was confirmed by a set of complementary techniques. Magnetic studies indicate that the POMs are magnetically well isolated. Remarkably, in Fe6W18@Gel, the SMM properties of the embedded molecules are close to those of the crystals, with clear quantum tunneling steps in the hysteresis loops. For the Fe6W18@UiO‐67 composite, the molecules retain their SMM properties, the energy barrier being slightly reduced in comparison to the crystalline material and the molecules exhibiting a tunneling rate of magnetization significantly faster than for Fe6W18@Gel. When Fe6W18 is introduced into MIL‐101(Cr), the width of the hysteresis loops is drastically reduced and the quantum tunneling steps are smeared out because of the magnetic interactions between the antiferromagnetic matrix and the SMM guest molecules. 相似文献
9.
Diego Mateo Andrea Santiago‐Portillo Josep Albero Sergio Navaln Mercedes Alvaro Hermenegildo García 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(49):18007-18012
Prolonged (weeks) UV/Vis irradiation under Ar of UiO‐66(Zr), UiO66 Zr‐NO2, MIL101 Fe, MIL125 Ti‐NH2, MIL101 Cr and MIL101 Cr(Pt) shows that these MOFs undergo photodecarboxylation of benzenedicarboxylate (BDC) linker in a significant percentage depending on the structure and composition of the material. Routine characterization techniques such as XRD, UV/Vis spectroscopy and TGA fail to detect changes in the material, although porosity and surface area change upon irradiation of powders. In contrast to BCD‐containing MOFs, zeolitic imidazolate ZIF‐8 does not evolve CO2 or any other gas upon irradiation. 相似文献
10.
Tetrakis(p‐tolyl)oxalamidinato‐bis[acetylacetonatopalladium(II)] ([Pd2(acac)2(oxam)]) reacted with Li–C≡C–C6H5 in THF with formation of [Pd(C≡C–C6H5)4Li2(thf)4] ( 1a ). Reaction of [Pd2(acac)2(oxam)] with a mixture of 6 equiv. Li–C≡C–C6H5 and 2 equiv. LiCH3 resulted in the formation of [Pd(CH3)(C≡C–C6H5)3Li2(thf)4] ( 2 ), and the dimeric complex [Pd2(CH3)4(C≡C–C6H5)4Li4(thf)6] ( 3 ) was isolated upon reaction of [Pd2(acac)2(oxam)] with a mixture of 4 equiv. Li–C≡C–C6H5 and 4 equiv. LiCH3. 1 – 3 are extremely reactive compounds, which were isolated as white needles in good yields (60–90%). They were fully characterized by IR, 1H‐, 13C‐, 7Li‐NMR spectroscopy, and by X‐ray crystallography of single crystals. In these compounds Li ions are bonded to the two carbon atoms of the alkinyl ligand. 1a reacted with Pd(PPh3)4 in the presence of oxygen to form the already known complexes trans‐[Pd(C≡C–C6H5)2(PPh3)2] and [Pd(η2‐O2)(PPh3)2]. In addition, 1a is an active catalyst for the Heck coupling reaction, but less active in the catalytic Sonogashira reaction. 相似文献