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991.
Hattori T Toraishi T Tsuneda T Nagasaki S Tanaka S 《The journal of physical chemistry. A》2005,109(45):10403-10409
The axial water exchange on glycinatocopper(II) complexes was theoretically investigated by using density functional theory (DFT) calculations. Glycinatocopper(II) complexes are well-known by the diffusion controlled exchange of axial ligands. Calculations using explicitly coordinating water molecules and solvent models showed that bis-glycinatocopper(II) complexes have a four-coordinate planar structure, in which waters are excluded from the axial positions of Cu(II) due to the Jahn-Teller effect. This may be because coordinating axial waters induce the discrepancy in the most stable ligand field splittings of inner 3d and outer 4d orbitals of the Cu(II) cation. To estimate the reactivity of the axial water exchange, we calculated the rate constant by calculating Gibbs free energies for the activation. As a result, we obtained the rate constant as k = 3.61 x 10(10) s(-1) in aqueous solution at T = 298.15 K. This rate constant is slightly larger than that of the diffusion controlled exchange of axial waters, which is experimentally observed in the order of 10(9) s(-1). Finally, we determined the structures of tris-glycinatocopper(II) complexes. It was consequently found that the third glycine is coordinated to Cu with the amino groups as experimentally observed. 相似文献
992.
Wakabayashi R Kubo Y Hirata O Takeuchi M Shinkai S 《Chemical communications (Cambridge, England)》2005,(46):5742-5744
Template assisted olefin metathesis of an allosteric host to give the corresponding bicyclic compound was achieved and can allosterically bind the template guest diamines, and with different affinity and cooperativity. 相似文献
993.
Kamiya K Tanaka Y Endang H Umar M Satake T 《Chemical & pharmaceutical bulletin》2005,53(12):1597-1599
From the fruits of Morinda citrifolia L., one new anthraquinone, 5,15-O-dimethylmorindol, together with five known anthraquinones and one new iridoid, morindacin, together with two known iridoids, were isolated. Their structures were elucidated by analysis of spectroscopic data. 相似文献
994.
Ohkubo T Konishi T Hattori Y Kanoh H Fujikawa T Kaneko K 《Journal of the American Chemical Society》2002,124(40):11860-11861
Hydration structures of "nanosolutions" around both cation and anion for rubidium bromide confined in nanospaces (pore width = 1.1 nm) of activated carbon fiber were determined with EXAFS measurements and related analysis. The analytical results indicate that the ionic solutions confined in hydrophobic nanospaces tend to form an incomplete dehydration structure, because of the spatial restriction by the nanospace and capturing water molecules in the ordered structure. 相似文献
995.
Hattori T Shimazumi Y Yamabe O Koshiishi E Miyano S 《Chemical communications (Cambridge, England)》2002,(19):2234-2235
A naturally occurring 1,1'-biphenanthrene, blestriarene C, was prepared and its absolute stereochemistry was determined to be Sa-(-) by an empirical method, during which the compound was found to undergo rapid photoracemization even under ambient light exposure. 相似文献
996.
Ryotaro Sekine Takashi Shibuya Kazuhiko Ukai Shinichi Komatsu Masayuki Hattori Toshifumi Mihashi Naoki Nakazawa Yoko Hirohara 《Optical Review》2006,13(4):207-211
The measurement of human ocular aberration is now frequently performed because of the increase in refractive surgery on the
human cornea. The Hartmann-Shack (H-S) wavefront sensor is considered to be the most useful wavefront sensor, and a calculation
method for wavefront aberration has been established. New methods of measuring wavefront aberrations of human eyes, using
the Talbot image of a two-dimensional grating as a wavefront sensor and local shift of the Talbot image to calculate tilt
of the wavefront are shown. The shift of the Talbot image was determined by comparing the phases of fundamental spatial frequency
between the grating and the local patch of the Talbot image by Fourier transformation. The actual experiment was performed
using a modified commercially available wavefront analyzer. Using these methods, Talbot images were obtained from model eyes
and a human eye, and wavefront shapes were successfully reconstructed. Wavefront aberrations can be measured even when the
obtained image is degraded by defocusing or scattering. 相似文献
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A combined system of a RuCl(2)(binap)(1,4-diamine) complex and t-C(4)H(9)OK in i-C(3)H(7)OH catalyzes enantioselective hydrogenation of various 1-tetralone derivatives and some methylated 2-cyclohexenones. Hydrogenation of 2-methyl-1-tetralone under dynamic kinetic resolution gives the cis alcohol with high ee. [reaction: see text] 相似文献