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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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(+)-{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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A faux hawk fullerene with PCBM-like properties

2014, San, Long K., Bukovsky, Eric V., Larson, Bryon W., Whitaker, James B., Deng, S.H.M., Kopidakis, Nikos, Rumbles, Garry, Popov, Alexey A., Chen, Yu-Sheng, Wang, Xue-Bin, Boltalina, Olga V., Strauss, Steven H.

Reaction of C60, C6F5CF2I, and SnH(n-Bu)3 produced, among other unidentified fullerene derivatives, the two new compounds 1,9-C60(CF2C6F5)H (1) and 1,9-C60(cyclo-CF2(2-C6F4)) (2). The highest isolated yield of 1 was 35% based on C60. Depending on the reaction conditions, the relative amounts of 1 and 2 generated in situ were as high as 85% and 71%, respectively, based on HPLC peak integration and summing over all fullerene species present other than unreacted C60. Compound 1 is thermally stable in 1,2-dichlorobenzene (oDCB) at 160 °C but was rapidly converted to 2 upon addition of Sn2(n-Bu)6 at this temperature. In contrast, complete conversion of 1 to 2 occurred within minutes, or hours, at 25 °C in 90/10 (v/v) PhCN/C6D6 by addition of stoichiometric, or sub-stoichiometric, amounts of proton sponge (PS) or cobaltocene (CoCp2). DFT calculations indicate that when 1 is deprotonated, the anion C60(CF2C6F5)− can undergo facile intramolecular SNAr annulation to form 2 with concomitant loss of F−. To our knowledge this is the first observation of a fullerene-cage carbanion acting as an SNAr nucleophile towards an aromatic C–F bond. The gas-phase electron affinity (EA) of 2 was determined to be 2.805(10) eV by low-temperature PES, higher by 0.12(1) eV than the EA of C60 and higher by 0.18(1) eV than the EA of phenyl-C61-butyric acid methyl ester (PCBM). In contrast, the relative E1/2(0/−) values of 2 and C60, −0.01(1) and 0.00(1) V, respectively, are virtually the same (on this scale, and under the same conditions, the E1/2(0/−) of PCBM is −0.09 V). Time-resolved microwave conductivity charge-carrier yield × mobility values for organic photovoltaic active-layer-type blends of 2 and poly-3-hexylthiophene (P3HT) were comparable to those for equimolar blends of PCBM and P3HT. The structure of solvent-free crystals of 2 was determined by single-crystal X-ray diffraction. The number of nearest-neighbor fullerene–fullerene interactions with centroid⋯centroid (⊙⋯⊙) distances of ≤10.34 Å is significantly greater, and the average ⊙⋯⊙ distance is shorter, for 2 (10 nearest neighbors; ave. ⊙⋯⊙ distance = 10.09 Å) than for solvent-free crystals of PCBM (7 nearest neighbors; ave. ⊙⋯⊙ distance = 10.17 Å). Finally, the thermal stability of 2 was found to be far greater than that of PCBM.

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Di-μ-chlorido-bis­­({4-[bis­(tri­methylsilyl)amino]-6-chloro-2,2,8,8-tetra­methyl-5,7-bis­(tri­methylsilyl)-3,5,7-tri­aza-4,6-diphospha-2,8-disilanon-3-en-4-ido-κ2P,P′}palladium(II)) di­ethyl ether disolvate

2016, Höhne, Martha, Müller, Bernd H., Spannenberg, Anke, Rosenthal, Uwe

The title compound, [Pd2(C18H54Cl2N4P2Si6)2Cl2]·2C4H10O, features a dinuclear chloride-bridged palladium complex bearing two equivalents of the novel monoanionic mixed valent (λ3-P)—N—(λ5-P) ligand. A metal catalyzed coupling of two amino­imino­phosphines and a shift of one chlorine from the metal to the phospho­rus results in the (λ3-P)—N—(λ5-P) ligand. The mol­ecule contains a planar bimetallic Pd2Cl2 core with a crystallographic centre of inversion at the mid-point of the Pd⋯Pd line. The Pd atoms are in a distorted square-planar arrangement, where the P/Pd/P and Cl/Pd/Cl planes are twisted with respect to each other by a dihedral angle of 7.57 (4)°. The P—Pd—P bite angle is 71.380 (18)°. Intra­molecular C—H⋯Cl inter­actions are observed. In the crystal, the diethyl ether solvent mol­ecule is disordered over two sites, with an occupancy ratio of 0.788 (5):0.212 (5).

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Intermolecular hydrogen bonding in isostructural pincer complexes [OH-(t-BuPOCOPt-Bu)MCl] (M = Pd and Pt)

2019, Joksch, M., Spannenberg, A., Beweries, T.

In the crystal structure of the isostructural title compounds, namely {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridopalladium(II), [Pd(C22H39O3P2)Cl], 1, and {2,6-bis[(di-tert-butylphosphanyl)oxy]-4-hydroxyphenyl}chloridoplatinum(II), [Pt(C22H39O3P2)Cl], 2, the metal centres are coordinated in a distorted square-planar fashion by the POCOP pincer fragment and the chloride ligand. Both complexes form strong hydrogen-bonded chain structures through an interaction of the OH group in the 4-position of the aromatic POCOP backbone with the halide ligand.

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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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Layered manganese bismuth tellurides with GeBi4Te7- and GeBi6Te10-type structures: Towards multifunctional materials

2019, Souchay, Daniel, Nentwig, Markus, Günther, Daniel, Keilholz, Simon, de Boor, Johannes, Zeugner, Alexander, Isaeva, Anna, Ruck, Michael, Wolter, Anja U.B., Büchnerde, Bernd, Oeckler, Oliver

The crystal structures of new layered manganese bismuth tellurides with the compositions Mn0.85(3)Bi4.10(2)Te7 and Mn0.73(4)Bi6.18(2)Te10 were determined by single-crystal X-ray diffraction, including the use of microfocused synchrotron radiation. These analyses reveal that the layered structures deviate from the idealized stoichiometry of the 12P-GeBi4Te7 (space group P3m1) and 51R-GeBi6Te10 (space group R3m) structure types they adopt. Modified compositions Mn1-xBi4+2x/3Te7 (x = 0.15-0.2) and Mn1-xBi6+2x/3Te10 (x = 0.19-0.26) assume cation vacancies and lead to homogenous bulk samples as confirmed by Rietveld refinements. Electron diffraction patterns exhibit no diffuse streaks that would indicate stacking disorder. The alternating quintuple-layer [M2Te3] and septuple-layer [M3Te4] slabs (M = mixed occupied by Bi and Mn) with 1 : 1 sequence (12P stacking) in Mn0.85Bi4.10Te7 and 2 : 1 sequence (51R stacking) in Mn0.81Bi6.13Te10 were also observed in HRTEM images. Temperature-dependent powder diffraction and differential scanning calorimetry show that the compounds are high-temperature phases, which are metastable at ambient temperature. Magnetization measurements are in accordance with a MnII oxidation state and point at predominantly ferromagnetic coupling in both compounds. The thermoelectric figures of merit of n-type conducting Mn0.85Bi4.10Te7 and Mn0.81Bi6.13Te10 reach zT = 0.25 at 375 °C and zT = 0.28 at 325 °C, respectively. Although the compounds are metastable, compact ingots exhibit still up to 80% of the main phases after thermoelectric measurements up to 400 °C. © The Royal Society of Chemistry 2019.

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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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1,1-Bis(di­phenyl­phosphor­yl)hydrazine

2018, Höhne, Martha, Aluri, Bhaskar R., Spannenberg, Anke, Müller, Bernd H., Peulecke, Normen, Rosenthal, Uwe

The title compound, C24H22N2O2P2, contains a diphosphazane backbone, as well as a hydrazine entity. The P—N—P diphosphazane unit and the N-amine N atom are almost coplanar, and the O atoms of the Ph2P(O) units are oriented trans to each other with respect to the P...P axis. In the crystal, centrosymmetrically related mol­ecules are linked into dimers by pairs of N—H...O hydrogen bonds, forming rings of graph-set motif R22(10).