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    Crystal structure of (2S,4S,7S)-7,7-dichloro-4-(1-chloro-1-methylethyl)-1- (2,2,2-trichloroethyl)bicyclo[4.1.0]heptane, C12H16Cl 6
    (Berlin : de Gruyter, 2009) Boualy, B.; el Firdoussi, L.; Ali, M.A.; Karim, A.; Spannenberg, A.
    C12H16Cl6, orthorhombic, P2 12121 (no. 19), a = 6.0742(3) Å, b = 9.7189(6) Å, c = 26.700(1) Å, V = 1576.2 Å3, Z = 4, Rgt(F) = 0.019, wRref(F2) = 0.045, T= 200 K. © by Oldenbourg Wissenschaftsverlag.
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    Diacetonitrile[N,N′-bis(2,6-diisopropyl-phenyl)ethane-1,2-diimine] dichloridochromium(II) acetonitrile solvate
    (Chester : International Union of Crystallography, 2009) Peitz, S.; Peulecke, N.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.
    The title compound, [CrCl2(CH3CN)2(C 26H36N2)]·CH3CN, was synthesized by the reaction of CrCl2(THF)2 with N,N′-bis-(2,6- diisopropyl-phen-yl)ethane-1,2-diimine in dichloro-methane/acetonitrile. The chromium center is coordinated by two N atoms of the chelating diimine ligand, two chloride ions in a trans configuration with respect to each other, and by two N atoms of two acetonitrile mol-ecules in a distorted octa-hedral geometry.
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    Crystal structure of rac-[1, 2-ethylene-bis(η5-4, 5, 6, 7-tetrahydroindenyl)]1-hafna-4, 5-bis(trimethylsilyl)furan-3-one- tris(pentafluorophenyl)borane, (C20H24)Hf(Me 3SiC2SiMe3CO2)B(C6F 5)3
    (Berlin : de Gruyter, 2009) Beweries, T.; Burlakov, V.V.; Rosenthal, U.; Spannenberg, A.
    C47H42BF15HfO2Si2, monoclinic, P121/n1 (no. 14), a = 15.7496(4) Å = 20.4074(5) Å= 16.3115(5) Å, β = 96.313(2)°, V= 5210.9 Å3, Z = 4, Rgt(F) = 0.027, WRref(F 2) = 0.049, T= 200 K. © by Oldenbourg Wissenschaftsverlag.
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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
    (Chester : International Union of Crystallography, 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.
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    Perfluoroalkylfullerenes
    (Washington, DC : ACS Publ., 2015) Boltalina, Olga V.; Popov, Alexey A.; Kuvychko, Igor V.; Shustova, Natalia B.; Strauss, Steven H.
    New chemical derivatives that possess the greatest variety of addition patterns than any other class of fullerene derivatives represent an important addition to the existing classes of perfluorocarbons, that is, compounds that are composed only of the two types of atoms, carbon and fluorine. These include aromatic and aliphatic perfluorocarbons such as perfluorodecalin, perfluorononane, hexafluorobenzene, etc., which are important as fluorous solvents used in medicine. The propensity of perfluoroalkylfullerenes (PFAFs) to readily crystallize from organic solutions upon slow evaporation in open air provided a straightforward access to their molecular structures via X-ray crystallography. Another crucial aspect that ensures future success in the characterization of numerous PFAFs of higher fullerenes and endohedral metallofullerenes is the possibility to apply HPLC methodologies to the separation of product mixtures. PFAFs, especially those of C60 and C70, are unique fullerene derivatives in terms of the number of structurally characterized derivatives with different number of RF groups and different addition patterns.
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    Crystal structure of (η4-cycloocta-1,5-dien)-N-(2- (diphenylphosphinooxy)-3-(naphthalen-1-yloxy)propyl)-N-(pentan-3-yl)-1, 1-diphenylphosphinamine-rhodium(I) tetrafluoroborate, [Rh(C8H 12)(C42H43NO2P2)][BF 4]
    (Berlin : de Gruyter, 2007) Dai, Z.; Heller, D.; Preetz, A.; Drexler, H.-J.
    C50H55BF4NO2P2Rh, monoclinic, P1211 (no. 4), a = 12.722(3) Å, b = 15.248(3) Å, c = 12.818(3) Å, β = 115.80(3)°, V = 2238.7 Å3, Z = 2, Rgt(F) = 0.036, wRref(F 2) = 0.079, T = 200 K. © by Oldenbourg Wissenschaftsverlag.
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    Crystal structure of η5-3,6-di-tert-butyl-4- (tris(pentafluorophenyl)boranyloxycarbonyl)-5-(η5- tetramethylcyclopentadienyl-methyl-9,10,11-trimethyl-bicyclo(6.3.0) undeca-4-en-8,10-dienyl)titanium(III) toluene hemisolvate, Ti(C 51H47BF15O2) · 0.5C 7H8
    (Berlin : de Gruyter, 2008) Spannenberg, A.; Burlakov, V.V.; Rosenthal, U.
    C54.50H51BF15O2Ti, triclinic, P1̄ (no. 2), a = 11.603(2) Å, b = 12.872(3) Å, c = 18.142(4) Å, α = 76.47(3)°, β = 77.99(3)°, γ = 69.13(3)°, V = 2438.2 Å5, Z = 2, Rgt(F) = 0.048, wRobs(F2) = 0.114, T = 200 K. © by Oldenbourg Wissenchaftsverlag.
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    Cooperative catalytic methoxycarbonylation of alkenes: Uncovering the role of palladium complexes with hemilabile ligands
    (Cambridge : RSC, 2018) Dong, Kaiwu; Sang, Rui; Wei, Zhihong; Liu, Jie; Dühren, Ricarda; Spannenberg, Anke; Jiao, Haijun; Neumann, Helfried; Jackstell, Ralf; Franke, Robert; Beller, Matthias
    Mechanistic studies of the catalyst [Pd2(dba)3/1,1′-bis(tert-butyl(pyridin-2-yl)phosphanyl)ferrocene, L2] for olefin alkoxycarbonylation reactions are described. X-ray crystallography reveals the coordination of the pyridyl nitrogen atom in L2 to the palladium center of the catalytic intermediates. DFT calculations on the elementary steps of the industrially relevant carbonylation of ethylene (the Lucite α-process) indicate that the protonated pyridyl moiety is formed immediately, which facilitates the formation of the active palladium hydride complex. The insertion of ethylene and CO into this intermediate leads to the corresponding palladium acyl species, which is kinetically reversible. Notably, this key species is stabilized by the hemilabile coordination of the pyridyl nitrogen atom in L2. The rate-determining alcoholysis of the acyl palladium complex is substantially facilitated by metal-ligand cooperation. Specifically, the deprotonation of the alcohol by the built-in base of the ligand allows a facile intramolecular nucleophilic attack on the acyl palladium species concertedly. Kinetic measurements support this mechanistic proposal and show that the rate of the carbonylation step is zero-order dependent on ethylene and CO. Comparing CH3OD and CH3OH as nucleophiles suggests the involvement of (de)protonation in the rate-determining step.
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    Crystal structure of (2,3-bis((2R,5R)-2,5-dimethylphosphonalyl)maleic anhydride)-(η4-norbornadiene)-rhodium(I) tetrafluoroborate, [Rh(C7H8)(C16H24O3P 2)] [BF4]
    (Berlin : de Gruyter, 2007) Holz, J.; Börner, A.; Heller, D.; Drexler, H.-J.
    C23H32BF4O3P2Rh, orthorhombic, P212121 (no. 19), a = 10.147(2) Å, b = 13.246(3) Å, c = 18.827(4) Å, V = 2530.5 Å3, Z = 4, Rgt(F) = 0.025, wRref(F 2) = 0.067, T = 200 K. © by Oldenbourg Wissenschaftsverlag,.
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    Crystal structure of bis(π-allylvalencene)dichlorodipalIadium, [PdCl(C15H23)]2
    (Berlin : de Gruyter, 2009) El Farrouji, A.; El Firdoussi, L.; Ali, M.A.; Karim, A.; Spannenberg, A.
    C30H46Cl2Pd2, monoclinic, Cl21 (no. 5), a = 22.0083(6) Å, b = 6.1827(2) Å, c = 21.5654(7) Å, β = 91.252(2)°, V= 2933.7 Å3, Z = 4, Rgr(F) = 0.019, wRref(F2) = 0.039, T = 200K. © by Oldenbourg Wissenschaftsverlag, München.