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31.
Paul Binger Michael J Doyle John McMeeking Carl Krüger Yi-Hung Tsay 《Journal of organometallic chemistry》1977,135(3):405-414
Oxidative addition of 2 molecules of 3,3-dimethylcyclopropene (I) to α,α′-bipyridyl(1,5-cyclooctadiene)nickel(0) (III) gave the title compound (IV) in over 90% yield. Complex IV was characterized by mass, 1H NMR and 13C NMR spectroscopy. Its structure was determined by X-ray diffraction (a 13.7081(2), b 14.638(2), c 9.5139(1) Å, β 110.82(1)°, C2/c, R = 0.05 for 1614 reflections). 相似文献
32.
Structural investigations of thin films of SiC, SiC with free silicon and various titanium suicides (TiSi2, TiSi and Ti5Si3) are described. The crystal phases have been identified using X-ray diffractometry. The growth of reaction products from surface reactions between silicon and deposited titanium can be observed.Dedicated to Professor Dr. rer.nat. Dr. h.c. Hubertus Nickel on the occasion of his 65th birthday 相似文献
33.
V. S. Lenenko P. Kränke M. Wahren V. B. Shur M. E. Vol'pin 《Russian Chemical Bulletin》1995,44(7):1293-1299
The interaction of labeled dinitrogen complexescis-(Me2PhP)4Mo(15N2)2 andtrans-(dppe)2W(15N2)2 with non-labeled nitronium and nitrosonium fluoroborates,14NO2BF4 and14NOBF4, in sulfolane at room temperature in the presence of H2SO4 results in rapid formation of labeled nitrous and nitric oxides (15N14NO,15NO), as well as15N14N. The yield of the products depends on the reagent ratio and reaches 10–20 mol. % per mole of a complex under optimum conditions. The mechanism of the reactions found is proposed. It involves the step of protonation of the dinitrogen ligand to form the corresponding hydrazido(2–) derivatives, which are then attacked by nitronium or nitrosonium cations. In accordance with the mechanism proposed, it was established that the hydrazido(2–) complexes, (Me2PhP)3Mo(15N2H2)Cl2 and (dppe)2W(15N2H2)Cl2, are capable of forming15N14NO,15NO, and15N14N under the action of14NO2BF4 and14NOBF4 in the absence of an acid.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 13–13, July, 1995. 相似文献
34.
Sucrose ethyleneoxide adducts have been prepared by reaction of sucrose with various amounts of ethyleneoxide inDMSO. The resulting polypode molecules were found to be efficient phase transfer catalysts in nucleophilic substitutions, oxidation and dichlorcarbene generation. Polymerisable polypodes have been obtained by reaction of sucrose ethyleneoxide adducts with methacrylic anhydride or methacryloylchloride in pyridine. Free radical polymerisation of the resulting mixtures of mono- and polyfunctional methacrylic esters of sucrose ethyleneoxide adducts yielded crosslinked gels. These polymer-supported octopus-molecules were found to be efficient triphase catalysts. 相似文献
35.
Reaction of (η-C5H4CH3)2TiCl2 with CH3OCH2MgCl yielded (η-C5H4-CH3)2Ti(Cl)CH2OCH3 (2a). Complex 2a crystallizes in space group P21/n with cell constants a 8.162(1), b 11.004(2), c 15.297(2) Å, β 96.40(1)°. In contrast to the three-membered metallacyclic zirconium compound of analogous composition (η-C5H5)2Zr(Cl)CH2OCH3 (1), the titanocenyl-substituted ether 2a has an open-chain (η1-O“-outside”) type structure. 相似文献
36.
W. Lautsch W. Broser W. Bandel W. Biedermann W. Gehrmann E. Schröder H. Gnichtel I. Zehmisch G. Kurth R. Krüger H. J. Kraege 《Colloid and polymer science》1954,138(3):129-142
Ohne Zusammenfassung
Die Arbeit wurde aus Mitteln des Marshall-Planes (ERP-Mittel) und mit Spenden aus dem „Fonds Chemie“ ausgeführt. Wir sprechen
den zust?ndigen Stellen für die Gew?hrung der Beihilfe unseren verbindlichsten Dank aus. Der Deutschen Forschungsgemeinschaft
danken wir für die überlassung einer Ultrazentrifuge, den Behring-Werken für die uns zur Verfügung gestellten Serumalbumin-
und -globulin-Pr?parate. 相似文献
37.
38.
We investigated the performance of the approximative density functional method DFTB versus BLYP and G2 with respect to zero-point corrected reaction energies, vibrational frequencies, and geometry parameters for a set of 28 reactions and 22 representative molecules containing C, H, N, and O (DFTB--density-functional based tight-binding approximation). The DFTB reaction energies show a mean absolute deviation versus the G2 reference of 4.3 kcalmol only. The corresponding value for the vibrational frequencies amounts to 75 cm(-1) versus BLYP/cc-pVTZ. With very few exceptions bond lengths and angles are in excellent agreement with the results of higher-level methods. 相似文献
39.
P.W. Jolly C. Krüger R. Salz J.C. Sekutowski 《Journal of organometallic chemistry》1979,165(3):C39-C42
The stoichiometric reaction between allene, zerovalent nickel and a chelating diphosphane leads to the formation of a bis-methylenenickelacyclopentane derivative whose structure has been established by X-ray crystallography. 相似文献
40.
Liliana Cseh Carol Csunderlik Ingo Pantenburg Gerd Meyer Otilia Costisor 《无机化学与普通化学杂志》2003,629(6):985-988
The complex Co(C14H13NO)2Cl2 with the protonated N‐salicylidene‐p‐toluidine ligand was synthesized from an ethanolic solution of CoCl2·6H2O and N‐salicylidene‐p‐toluidine. The crystal structure was determined from X‐ray single crystal data (monoclinic, space group Cc, a = 1496.2(3) pm, b = 1257.4(4) pm, c = 1544.6(3) pm, β = 115.01(1)°, Z = 4). Co2+ adopts a distorted tetrahedral geometry. The UV‐Vis and IR spectra of the complex are discussed. 相似文献