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Iodidobis(≠5-penta-methyl-cyclo-penta-dien-yl)titanium(III)

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.

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(tert-Butylimido)bis(η5-cyclopenta-dienyl) pyridinezirconium(IV)

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.

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ZnO Nanoparticles Encapsulated in Nitrogen-Doped Carbon Material and Silicalite-1 Composites for Efficient Propane Dehydrogenation

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)

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Bis(dimethyl sulfoxide)hydridobis(triphenylphosphane)cobalt(I)

2010, Hapke, M., Weding, N., Spannenberg, A.

The title compound, [CoH(C18H15P)2(C 2H6OS)2], was synthesized by the reaction of chloridotris(triphenyl-phosphane)cobalt(I), [ClCo(PPh3)3], in the presence of one equivalent potassium hydridotris(pyrazol-yl)borate in dimethyl sulfoxide. The structure displays a distorted trigonal-pyramidally coordinated cobalt(I) atom, with two phosphane ligands and one DMSO ligand in the equatorial plane. The coordination is completed by one further DMSO ligand and the anionic hydride in the axial positions.

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[2,2-Bis(diphenylphosphanyl)propane κ2P,P0] tetracarbonylchromium(0)dichloromethane monosolvate

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)°.

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[Bis(diphenylphosphanyl)dimethylsilane κ2P,P′] tetracarbonylchromium(0)

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)°.

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Nickel-Catalyzed Carbonylative Synthesis of Functionalized Alkyl Iodides

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.

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(+)-{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

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.

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Bio-based building blocks from 5-hydroxymethylfurfural via 1-hydroxyhexane-2,5-dione as intermediate

2019, Wozniak, Bartosz, Tin, Sergey, de Vries, Johannes G.

The limits to the supply of fossil resources and their ever increasing use forces us to think about future scenarios for fuels and chemicals. The platform chemical 5-hydroxymethyl-furfural (HMF) can be obtained from biomass in good yield and has the potential to be converted in just a few steps into a multitude of interesting products. Over the last 20 years, the conversion of HMF to 1-hydroxyhexane-2,5-dione (HHD) has been studied by several groups. It is possible to convert HMF into HHD by hydrogenation/hydrolytic ring opening reaction in aqueous phase using various heterogeneous and homogeneous catalysts. This review addresses both the state of the art of HHD synthesis, including mechanistic aspects of its formation, as well as the recent progress in the application of HHD as a building block for many useful chemicals including pyrroles, cyclopentanone derivatives and triols. © 2019 The Royal Society of Chemistry.

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(+)-{1,2-Bis[(2R,5R)-2,5-dimethyl-phospho-lan-1-yl]ethane- κ2 P,P′}(η4-cyclo-octa-1,5-diene) rhodium(I) tetra-fluorido-borate

2010, Schulz, S., Drexler, H.-J., Heller, D.

The title compound, [Rh(C8H12)(C14H 28P2)]BF4, exhibits a rhodium(I) complex cation with a bidentate bis-phosphine ligand and a bidentate η2, η2-coordinated cyclo-octa-1,5-diene. Together the ligands create a slightly distorted square-planar cordination environment for the Rh(I) atom. There are three mol-ecules in the asymmetric unit and intra-molecular P - Rh - P bite angles of 82.78 (5), 82.97 (6) and 83.09 (5)° are observed. The dihedral angles between the P - Rh - P and the X - Rh - X planes (X is the centroid of a double bond) are 14.7 (1), 14.8 (1) and 15.3 (1)°. The structure exhibits disorder of one cyclo-octa-diene ligand as well as one BF4 anion.