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- ItemNickel-Catalyzed Carbonylative Synthesis of Functionalized Alkyl Iodides(Amsterdam : Elsevier B.V., 2018) Peng, J.-B.; Wu, F.-P.; Xu, C.; Qi, X.; Ying, J.; Wu, X.-F.Chemistry; Catalysis; Organic Synthesis © 2018 The Author(s)Functionalized alkyl iodides are important compounds in organic chemistry and biology. In this communication, we developed an interesting nickel-catalyzed carbonylative synthesis of functionalized alkyl iodides from aryl iodides and ethers. With Mo(CO)6 as the solid CO source, both cyclic and acyclic ethers were activated, which is also a challenging topic in organic synthesis. Functionalized alkyl iodides were prepared in moderate to excellent yields with outstanding functional group tolerance. Besides the high value of the obtained products, all the atoms from the starting materials were incorporated in the final products and the reaction had high atom efficiency as well.
- ItemCrystal structure of bis(pentamethylcyclopentadienyl)-(4,4′-di-tert- butylbipyridyl)hafnium(IV)-hexane (1:0.5), Hf(C10H15) 2(C18H24N2) · 0.5C 6H14(Berlin : de Gruyter, 2010) Beweries, T.; Spannenberg, A.; Rosenthal, U.C41H61HfN2, monoclinic, P21/n (no. 14), a = 13.4410(4) Å, b = 13.9983(6) Å, c = 21.1996(8) Å, β = 98.144(3)°, V = 3948.5 Å3, Z = 4, Rgt(F) = 0.051, wRref(F2) = 0.121,T = 200 K. © 2014 Oldenbourg Wissenschaftsverlag, München.
- ItemCrystal structure of 1-bis(((1R,2S,5R)-2-isopropyl-5-methylcyclohexyl) cyclopentadienyl)-1-trimethylphosphine-2,3-bis(trimethylsilyl) -1-hafnacycloprop-2-ene-hexane (1:0.5), (HfC8H18Si 2)(C15H22)2(PC3H 9) · 0.5C6H14(Berlin : de Gruyter, 2010) Klahn, M.; Spannenberg, A.; Rosenthal, U.C44H78HfPSi2, tetragonal, P4 1212 (no. 92), a = 14.9634(2) Å, c = 44.9270(8) Å, V = 10059.3 Å3, Z = 8, Rgt(F) = 0.026, wRref(F2) = 0.073, T = 200 K. © by Oldenbourg Wissenschaftsverlag, München.
- ItemCrystal structure of bis(pentamethylcyclopentadienyl)(1-tert- butylisocyanido)-2-trimethylsilyl-3-[(trimethylsilyl)ethynyl]-hafnacyclopropene, (C10H15)2(C5H9N) Hf(C10H18Si2)(Berlin : de Gruyter, 2010) Beweries, T.; Spannenberg, A.; Rosenthal, U.C35H57HfNSi2, monoclinic, P121/c1 (no. 14), a = 10.7410(3) Å, b = 16.2302(5) Å, c = 21.6945(7) Å, β = 104.512(2)°, V = 3661.3 Å3, Z = 4, R gt(F) = 0.049, wRref(F2) = 0.138, T = 200 K. © 2014 Oldenbourg Wissenschaftsverlag, München.
- ItemZnO Nanoparticles Encapsulated in Nitrogen-Doped Carbon Material and Silicalite-1 Composites for Efficient Propane Dehydrogenation(Amsterdam [u.a.] : Elsevier, 2019) Zhao, Dan; Li, Yuming; Han, Shanlei; Zhang, Yaoyuan; Jiang, Guiyuan; Wang, Yajun; Guo, Ke; Zhao, Zhen; Xu, Chunming; Li, Ranjia; Yu, Changchun; Zhang, Jian; Ge, Binghui; Kondratenko, Evgenii V.Chemistry; Catalysis; Nanoparticles © 2019 The Author(s)Non-oxidative propane dehydrogenation (PDH)is an attractive reaction from both an industrial and a scientific viewpoint because it allows direct large-scale production of propene and fundamental analysis of C-H activation respectively. The main challenges are related to achieving high activity, selectivity, and on-stream stability of environment-friendly and cost-efficient catalysts without non-noble metals. Here, we describe an approach for the preparation of supported ultrasmall ZnO nanoparticles (2–4 nm, ZnO NPs)for high-temperature applications. The approach consists of encapsulation of NPs into a nitrogen-doped carbon (NC)layer in situ grown from zeolitic imidazolate framework-8 on a Silicalite-1 support. The NC layer was established to control the size of ZnO NPs and to hinder their loss to a large extent at high temperatures. The designed catalysts exhibited high activity, selectivity, and on-stream stability in PDH. Propene selectivity of about 90% at 44.4% propane conversion was achieved at 600°C after nearly 6 h on stream. © 2019 The Author(s)
- ItemIodidobis(≠5-penta-methyl-cyclo-penta-dien-yl)titanium(III)(Chester : International Union of Crystallography, 2010) Kessler, M.; Spannenberg, A.; Rosenthal, U.In the title complex mol-ecule, [Ti(C10H15) 2I], the paramagnetic Ti(III) atom is coordinated by two penta-methyl-cyclo-penta-dienyl (Cp*) ligands and one iodide ligand. The two Cp*ligands are in a staggered orientation. The coordination geometry at the titanium atom can be described as distorted trigonal-planar.
- Item[2,2-Bis(diphenylphosphanyl)propane κ2P,P0] tetracarbonylchromium(0)dichloromethane monosolvate(Chester : International Union of Crystallography, 2010) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.The title compound, [Cr(C27H26P2)(CO) 4]·CH2Cl2, was obtained by the reaction of Ph2PCMe2PPh2 with Cr(CO)6 in refluxing toluene by substitution of two carbonyl ligands. The CrC 4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 70.27 (2)°.
- Item(+)-{1,2-Bis[(2R,5R)-2,5-diethyl-phospho-lan-1-yl]ethane- κ2 P,P′}(≠4-cyclo-octa-1,5-diene)rhodium(I) tetra-fluoridoborate(Chester : International Union of Crystallography, 2010) Schulz, S.; Fischer, C.; Drexler, H.-J.; Heller, D.The title compound, [Rh(C8H12)(C18H 36P2)]BF4, exhibits a rhodium(I) complex cation with a bidentate bis-phosphine ligand and a bidentate 2, 2-coordinated cyclo-octa-1,5-diene ligand. The ligands form a slightly distorted square-planar coordination environment for the Rh(I) atom. An intra-molecular P-Rh-P bite angle of 83.91 (2)° is observed. The dihedral angle between the P - Rh - P and the X - Rh - X planes (X is the centroid of a double bond) is 14.0 (1)°. The BF4 anion is disordered over two positions in a 0.515 (7):0.485 (7) ratio.
- Item(tert-Butylimido)bis(η5-cyclopenta-dienyl) pyridinezirconium(IV)(Chester : International Union of Crystallography, 2010) Kaleta, K.; Arndt, P.; Spannenberg, A.; Rosenthal, U.The title compound, [Zr(C5H5)2(C 4H9N)(C5H5N)], was obtained from the reaction of (C5H5)2Zr(py)(η2- Me3SiC2SiMe3) (py is pyridine) and tBuN=C=NtBu alongside the formation of (C 5H5)2Zr(CNtBu)(2-Me 3SiC2SiMe3). The zirconium atom is coordinated in a distorted tetrahedral geometry by two cyclopentadienyl ligands, a pyridine ligand, and a tertbutylimido ligand via a Zr=N double bond. The tertbutyl group is disordered over two positions in a 0.634 (5):0.366 (5) ratio.
- Item[Bis(diphenylphosphanyl)dimethylsilane κ2P,P′] tetracarbonylchromium(0)(Chester : International Union of Crystallography, 2010) Peulecke, N.; Peitz, S.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.The title compound, [Cr(C26H26P2Si)(CO) 4], was obtained by the reaction of Ph2PSiMe 2PPh2 with Cr(CO)6 in refluxing toluene by ligand exchange. The CrC4P2 coordination geometry at the Cr atom is distorted octa-hedral, with a P - Cr - P bite angle of 80.27 (1)°.