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21.
Hans Schumann 《Journal of organometallic chemistry》1985,293(1):75-91
Reactions of reactive cyclopentadienyliron complexes C5H5Fe(CO)2I, [C5H5Fe(CO)2THF]BF4, [C5H5Fe(CO)((CH3)2S)2]BF4 and [C5H5Fe(p-(CH3)2C6H4)]PF6 with P(OR)3 as ligands (R = CH3, C2H5, i-C3H7 and C6H5) lead to the formation of the complex compounds C5H5Fe(CO)2?n(P(OR)3)nI and [C5H5Fe(CO)3?n(P(OR)3)n]X (n = 1, 2 and n = 1–3, X = BF4, PF6). Spectroscopic investigations (IR, 1H, 13C and 31P NMR) indicate an increase of electron density on the central metal with increasing substitution of CO groups by P(OR)3 ligands. The stability of the compounds increase in the same way. 相似文献
22.
Transition Metal Substituted Acylphosphanes and Phosphaalkenes. 17. Synthesis and Structure of the μ-Isophosphaalkyne Complexes [(η5-C5H5)2(CO)2Fe2(μ-CO)(μ-C?PC6H2R3)] (R = Me, iPr, tBu) . Condensation of (η5-C5H5)2(CO)2Fe2(μ-CO)(μ-CSMe)}+SO3CF3? ( 6 ) with 2,4,6-R3C6H2PH(SiMe3) ( 7 ) ( a : R = Me, b : R = iPr, c : R = tBu) affords the complexes (η5-C5H5)2(CO)2Fe2(μ-CO)(η-C?PC6H2R3-2,4,6) ( 9 a–c ) with edge-bridging isophosphaalkyne ligands as confirmed by the x-ray structure analysis of 9 a . 相似文献
23.
24.
B. Schumann 《Crystal Research and Technology》1981,16(10):1213-1213
25.
26.
I. L. Fedushkin A. N. Lukoyanov G. K. Fukin M. Hummert H. Schumann 《Russian Chemical Bulletin》2006,55(7):1177-1183
Reduction of benzophenone and 4,4′-bis(methoxy)benzophenone with the aluminum complex (dpp-BIAN)AlI(Et2O) (1) containing the dianionic dpp-BIAN ligand (dpp-BIAN is 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) affords the pinacolate
complexes [(dpp-BIAN)AlI]2[μ-O2C2Ph4] (2) and [(dpp-BIAN)AlI]2[μ-O2C2(C6H4OMe)4] (3), respectively, which undergo the pinacolone rearrangement upon prolonged storage in diethyl ether to form [(dpp-BIAN)AlI]2O (4). The reaction of 1 with fluoren-9-one produces stable pinacolate (dpp-BIAN)Al[μ-O2(C13H8)2] (7) and the (dpp-BIAN)AlI2 complex (8). Compounds 2—4, 7, and 8 were characterized by ESR spectroscopy. Hydrolysis products of compounds 2 and 3 were characterized by 1H NMR spectroscopy. The structures of complexes 4 and 7 were established by X-ray diffraction.
dpp-BIAN is 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1134–1140, July, 2006. 相似文献
27.
Espinoza LA Schumann KR Luk YY Israel BA Abbott NL 《Langmuir : the ACS journal of surfaces and colloids》2004,20(6):2375-2385
We report the orientational behavior of nematic phases of 4-cyano-4'-pentylbiphenyl (5CB) on cationic, anionic, and nonionic surfaces before and after contact of these surfaces with solutions containing the negatively charged vesicular stomatitis virus (VSV). The surfaces were prepared on evaporated films of gold by either adsorption of poly-L-lysine (cationic) or formation of self-assembled monolayers (SAMs) from HS(CH2)2SO3- (anionic) or HS(CH2)11(OCH2CH2)4OH (nonionic). Prior to treatment with virus, we measured the initial orientation of 5CB (delta epsilon = epsilon(parallel) - epsilon(perpendicular) > 0) to be parallel to the cationic surfaces (planar anchoring) but perpendicular (homeotropic) after equilibration for 5 days. A similar transition from planar to homeotropic orientation of 5CB was observed on the anionic surfaces. Only planar orientations of 5CB were observed on the nonionic surfaces. Because N-(4-methoxybenzylidene)-4-butylaniline (MBBA, delta epsilon = epsilon(parallel) - epsilon(perpendicular) < 0) exhibited planar alignment on all surfaces, the time-dependent alignment of 5CB on the ionic surfaces is consistent with a dipolar coupling between the 5CB and electrical double layers formed at the ionic interfaces. Treatment ofpoly-L-lysine-coated gold films (cationic) with purified solutions of VSV containing 10(8)-10(10) plaque-forming units per milliliter (pfu/mL) led to the homeotropic alignment of 5CB immediately after contact of 5CB with the surface. In contrast, treatment of anionic surfaces and nonionic surfaces with solutions of VSV containing approximately 10(10) pfu/mL did not cause immediate homeotropic alignment of 5CB. These results and others suggest that homeotropic alignment of 5CB on cationic surfaces treated with VSV of titer > or = 10(8) pfu/mL reflects the presence of virus electrostatically bound to these surfaces. 相似文献
28.
FTIR-spectroscopic investigations of catalytic reactions yield detailed information about the interaction of adsorbed molecules with the catalyst and kinetic data of the surface reaction, if the participating molecules show vibrations whose position and intensity in the IR-spectrum depend on the sorption state and the quantity adsorbed. In this paper, the possibilities and limitations of the method are represented by two examples. 相似文献
29.
30.
Khoroshen'kov G. V. Fag A. A. Bochkarev M. N. Dechert S. Schumann H. 《Russian Chemical Bulletin》2003,52(8):1715-1719
The reactions of LnI2 (Ln = Nd (1) or Dy (2)) with cyclopentadiene (CpH) in THF at 0 °C afforded the CpLnI2(THF)3 complexes in 65—67% yields. The reaction of thulium diiodide (3) with an excess of CpH at 60 °C produced CpTmI2(THF)3, Cp2TmI(THF)2, and TmI3(THF)3 in 21, 58, and 63% yields, respectively. The reactions of 1 and 2 with pentamethylcyclopentadiene (Cp*H) in THF were accompanied by disproportionation giving rise to the Cp*2LnI(THF)2 and LnI3(THF)
x
complexes. Neodymium triiodide was isolated in the ionic form [NdI2(THF)5]+[NdI4(THF)2]–. Its structure and the structure of CpTmI2(THF)3 were established by X-ray diffraction analysis. 相似文献