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51.
M. Tanaka Y. Minai T. Watanabe T. Tominaga 《Journal of Radioanalytical and Nuclear Chemistry》1992,164(4):255-264
Phthalocyanineiron(II) (FePc) and phthalocyaninato[(2-)bispyridine]iron(II) (FePc(py)2) synthesized in supercage of NaY, KY and RbY zeolite have been characterized by Mössbauer and ESR spectroscopy. The yield of formation of the pyridine adduct depends on the ionic radius of the alkali ions introduced into the supercage, but not on the number of iron ions trapped in the cages, suggesting that free space in the supercage was the most important factor for the formation of the FePc-py-adducts. 相似文献
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A single-component conducting molecular crystal composed of paramagnetic copper complexes, [Cu(dmdt)2]0+, was prepared. The crystal has an unprecedented three-dimensionally packed molecular arrangement and exhibits a fairly high conductivity (1 S cm-1 at room temperature). The magnetic susceptibility measurements revealed that [Cu(dmdt)2]0+ molecule keeps most of S = 1/2 spin moments. The difference of the bond lengths between [Cu(dmdt)2]0+ and [Cu(dmdt)2]2- is consistent with the result of the molecular orbital calculation. 相似文献
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Tanaka M Nakamura M Ikeda T Ikeda K Ando H Shibutani Y Yajima S Kimura K 《The Journal of organic chemistry》2001,66(21):7008-7012
Synthetic procedures for monoazathiacrown ethers were explored, and monoazatrithia-12-crown-4, monoazatetrathia-15-crown-5, and monoazapentathia-18-crown-6 were obtained in moderate yields by the reaction of bis(2-chloroethyl)amine with the appropriate dithiols in the presence of lithium hydroxide in THF. To evaluate metal-ion binding properties of the monoazathiacrown ethers by solvent extraction, lipophilic dodecyl and dodecanoyl groups were incorporated onto the monoazathiacrown ethers. The solvent extraction experiments suggested that monoazathiacrown ethers have Ag(+) and Hg(2+) selectivities and that the relative selectivity between Ag(+) and Hg(2+) depends on their nitrogen atom properties and numbers of sulfur atoms reflecting the respective affinities of nitrogen and sulfur atoms to Hg(2+) and Ag(+). An interesting ability to bind Mg(2+) was observed in the case of N-dodecyl monoazatrithia-12-crown-4. 相似文献
57.
Ohwada T Miura M Tanaka H Sakamoto S Yamaguchi K Ikeda H Inagaki S 《Journal of the American Chemical Society》2001,123(42):10164-10172
N-Nitrosamines can be considered as potential nitric oxide (NO)/nitrosonium ion (NO(+)) donors. However, the relation of the structures of N-nitrosamines, in particular of aliphatic N-nitrosamines, to the characteristics of release of NO or NO(+) remains unclear. Here we show that aliphatic N-nitrosoamines of 7-azabicyclo[2.2.1]heptanes can undergo heterolytic N-NO bond cleavage. On the basis of the observation of reduced rotational barriers of the N-NO bonds in solution and nitrogen-pyramidal structures of the N-nitroso group in the solid state, we postulate that N-NO bond cleavage of N-nitrosamines is enhanced by a reduction of the resonance in the N-NO group. Computational studies suggest that these structural features of the N-nitrosamines of 7-azabicyclo[2.2.1]heptane are derived from angle strain imposed on the CNC angles. 相似文献
58.
Racemic D,L-asparagine induced spontaneous asymmetric resolution of co-existing D,L-phenylalanine or D,L-tryptophan by recrystallization from a homogeneous aqueous solution, and the enantiomeric excess of phenylalanine or tryptophan in the resulting crystals correlated linearly with that of asparagine crystallized with phenylalanine or tryptophan. 相似文献
59.
[reaction: see text] The formal synthesis of the ocular age pigment A2-E was achieved by the efficient one-pot preparation of the substituted pyridine, which involves the aza-6pi-electrocyclization of the Schiff base derived from (E)-3-carbonyl-2,4,6-trienal followed by oxidation. 相似文献
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