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41.
Coronado E Gómez-García CJ Nuez A Romero FM Rusanov E Stoeckli-Evans H 《Inorganic chemistry》2002,41(18):4615-4617
The combination of hexacyanoferrate(III) anions, [Fe(CN)(6)](3)(-), with nickel(II) complexes derived from the chiral ligand trans-cyclohexane-1,2-diamine (trans-chxn) affords the enantiopure layered compounds [Ni(trans-(1S,2S)-chxn)(2)](3)[Fe(CN)(6)](2).2H(2)O (1) and [Ni(trans-(1R,2R)-chxn)(2)](3)[Fe(CN)(6)](2).2H(2)O (2). These chiral systems behave as ferromagnets (T(c) = 13.8 K) with a relatively high coercive field (H(c) = 0.17 T) at 2 K. They also exhibit an unusual magnetic behavior at low temperatures that has been attributed to the dynamics of the magnetic domains in the ordered phase. 相似文献
42.
A. A. Avetisyan I. L. Aleksanyan A. A. Pivazyan 《Chemistry of Heterocyclic Compounds》2005,41(4):471-474
A method has been developed for the synthesis of substituted 4-hydroxy- and 4-amino-2-methyl-3-(2-methylindol-3-yl)methylquinolines by treating the corresponding 4-hydroxy(chloro)-2-methyl-3-(3-oxobutyl)quinolines with phenylhydrazine hydrochloride. It was found that nucleophilic substitution occurred in the case of the 4-chloroquinolines together with subsequent rearrangement to give the 4-amino derivatives. The thiosemicarbazones of the corresponding 4-hydroxy-2-methyl-3-(3-oxobutyl)quinolines were also obtained.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 554–557, April, 2005. 相似文献
43.
Gerhard Schomburg Alfred Deege Heike Hinrichs Eduard Hübinger Heribert Husmann 《Journal of separation science》1992,15(9):579-584
Methods of alkylation of α-, β- and γ-cyclodextrins have been optimized with regard to the parameters of reaction, degree of alkylation and yields. The analysis of the reaction mixtures and of the isolated single species has been performed by high temperature GC and HPLC. The phase systems of the preferably applied HPLC have been carefully adjusted by variation of both the stationary and mobile phases to the very different hydrophobicities of the various alkylated CD species which have been synthesized. Several partially or fully alkylated CD species were isolated from preparative scale HPLC separations in high purity. 相似文献
44.
Operator realizations of matrix-valued Herglotz-Nevanlinna functions play an important and essential role in system theory, in the spectral theory of bounded nonselfadjoint operators, and in interpolation problems. Here, a generalization for realization results of the Brodskiǐ-Livsic type is given for Herglotz-Nevanlinna functions whose spectral measures are compactly supported. 相似文献
45.
Eduard E. Karslyan Andrew I. Konovalov Alexandra O. Borissova Pavel V. Petrovskii Alexander R. Kudinov 《Mendeleev Communications》2012,22(4):189-191
The [2 + 2] photodimerization of the complex [(C5Me4CH2OMe)Ru(η6-C12H8)]+ under visible-light irradiation leads to a mixture of the head-to-head heptacyclene products [(μ-η6: η6-C24H16)Ru2(C5Me4CH2OMe)2]2+ (syn- and anti-) with the predominant formation of the syn-isomer; the structures of both isomers were established by X-ray diffraction analysis. 相似文献
46.
47.
Eduard Feireisl 《偏微分方程通讯》2019,44(3):271-278
We show the weak–strong uniqueness property for the compressible Navier–Stokes system with general non-monotone pressure law. A weak solution coincides with the strong solution emanating from the same initial data as long as the latter solution exists. 相似文献
48.
Dr. Eduard Baal Marius Klein Dr. Klaus Harms Prof. Dr. Jörg Sundermeyer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(49):12610-12618
The synthesis of 2,9-diaza-1,3,8,10-tetratriflato-dibenzoperylene (DDP 3 a ) and corresponding 2,9-dimethyl-1,3,8,10-tetratriflato-dibenzoperylene (DBP 3 b ) has been developed at multigram scale via reduction of one of the industrially most important high-performance dyes, perylene-3,4,9,10-tetracarboxylic diimide (PTCDI), and of the corresponding dihydroxy peropyrenequinone precursor. The focus of this paper is on the reactivity pattern of 3 a as key intermediate towards highly functionalized 2,9-diazadibenzopyrelenes (DDPs) obtained via catalytic substitution of four triflate by aryl, heteroaryl, alkynyl, aminyl, and O-phosphanyl substituents. The influence of electron-donating substituents (OSiMe3, OPt-Bu2, N-piperidinyl), electron-withdrawing (OTf, 3,5-bis-trifluoromethyl-phenyl), and of electron-rich π-conjugated (2-thienyl, 4-tert-butylphenyl, trimethylsilyl-ethynyl) substituents on optoelectronic and structural properties of these functionalized DDPs has been investigated via XRD analyses, UV/Vis, PL spectroscopy, and by electroanalytical CV. These results were correlated to results of DFT and TD-DFT calculations. Thus, functionalized DPPs with easily tunable HOMO and LUMO energies and gap became available via a new and reliable synthetic strategy starting from readily available PTCDI. 相似文献
49.
Aida Avetisyan 《合成通讯》2013,43(17):2607-2609
A convenient procedure for the preparation of cerpegin is described. 相似文献
50.