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71.
The anionic triiron(III) cluster ligand [Fe(III)(3)(μ(3)-O)(bpca)(2)Cl(4)(EtO)(2)](-) (1; Hbpca=bis(2-pyridylcarbonyl)amine) was prepared as a building block for constructing larger metal assemblies. This "metal cluster complex ligand" was used in the synthesis of the mixed-valent heptairon complex [Fe(II)(1)(2)(EtOH)(2)], which has a ground-state spin value of S=12/2. 相似文献
72.
Kazuhiko Matsumoto Tetsuya Tsuda Toshiyuki Nohira Rika Hagiwara Yasuhiko Ito Osamu Tamada 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(3):m186-m187
In the title complex, (C6H11N2)3[LaCl6], centrosymmetric octahedral hexachlorolanthanate anions are located at the corners and face‐centers of the monoclinic unit cell. The ring H atoms of the cations interact with the Cl atoms of the anions via hydrogen bonding, and bifurcation of the hydrogen bonding is observed. Cation–cation interactions via hydrogen bonding between the ring H atoms and π‐electrons of aromatic rings are also observed as in other imidazolium salts. 相似文献
73.
74.
75.
76.
An antiviral nucleoside or virazole was synthesized efficiently and regioselectively starting with benzyl cyanoformate. 相似文献
77.
Vladimir Rapić Prof. Dr. Karl Schlögl Brigitte Steinitz 《Monatshefte für Chemie / Chemical Monthly》1977,108(4):767-780
Starting from optically active methylferrocene-- and--carboxylic acids (1 a and1 b) of known absolute configuration and enantiomeric purity about 15 chiral ferrocenes (of each isomeric series— and ) were obtained by suitable ligand transformations. Thereby (almost) all possible chiral combinations of the ligands CH3, COOH (COO–), COOCH3, CN and NH2 (NH3
+) were accessible which are necessary for a potential test of approximations of chirality functions for compounds with basic symmetry C5v. The chiroptical properties of these disubstituted ferrocenes are recorded.Preliminary tests using a shortened Ansatz revealed large discrepancies between calculated () and found [M]D-values. Possible reasons for this failure are discussed.
61. Mitt. über Ferrocenderivate
39. Mitt.:A. Meyer, H. Neudeck undK. Schlögl, Chem. Ber.110, 1403 (1977).
60. Mitt.:V. Rapi, K. Schlögl undB. Steinitz, J. Organometal. Chem.94, 87 (1975). 相似文献
61. Mitt. über Ferrocenderivate
39. Mitt.:A. Meyer, H. Neudeck undK. Schlögl, Chem. Ber.110, 1403 (1977).
60. Mitt.:V. Rapi, K. Schlögl undB. Steinitz, J. Organometal. Chem.94, 87 (1975). 相似文献
78.
79.
Dr. Geno Kynast 《Analytical and bioanalytical chemistry》1971,256(1):20-24
A computer program for direct evaluation of thin-layer chromatograms, which already was described earlier [3] has been tested with a laboratory and some technical formulations of a pesticide. Results have been compared with those obtained by two conventional methods. Mean relative standard deviation calculated from results compiled by electronic data processing (method A) is about 6%, compared to 10% received by graphic method (method C) which is employed by most investigators. In addition, overall time of analysis is 34% higher if graphic method is used. Method A saves time and expense especially in routine analysis because working of the process is easier and may be performed even by assistent personal. The proposed method is suitable for the determination of different active ingredients and impurities even in difficult technical products. 相似文献
80.
T Tatee K Narita S Kurashige S Ito H Miyazaki H Yamanaka M Mizugaki T Sakamoto H Fukuda 《Chemical & pharmaceutical bulletin》1986,34(4):1643-1655