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71.
Zhiou Li Hiromi Ishizuka Yoshihisa Sei Prof. Dr. Munetaka Akita Dr. Michito Yoshizawa 《化学:亚洲杂志》2012,7(8):1789-1794
Combining meta‐triphenylamine or triphenylphosphine with three anthracene fluorophores gives rise to fluorescent non‐planar triskelions 1 and 2 . The emissive properties of 1 are highly solvatochromic, yielding blue to pale green and even pale yellow fluorescence, whereas the blue emission of 2 is solvent‐insensitive. Anthracene trimers 1 and 2 are both emissive in the solid state, displaying yellow and pale green fluorescence, respectively, with moderate quantum yields. 相似文献
72.
73.
The adsorbed state of nitrogen on Ru catalysts was studied by a TPD technique combined with an isotopic technique. (1) A molecular and an atomic species on Ru powder, (2) a molecular and three atomic species on Raney-Ru, and (3) two molecular and probably three atomic species on Raney-Ru/K were identified, respectively. Relations between the adsorbed states and those reactivities for an isotopic equilibration reaction of N2 were discussed. 相似文献
74.
Tomoyuki Onishi 《Tetrahedron》2004,60(42):9503-9515
The structurally intriguing cell-cycle inhibitor spirotryprostatin A has been synthesized utilizing an azomethine ylide dipolar cycloaddition reaction as the key step. This pentacyclic alkaloid contains a prenylated tryptophan-derived oxindole moiety that has been created in a regiocontrolled and stereocontrolled manner in a single step. 相似文献
75.
Site-specific valence-band X-ray photoelectron spectra of SrTiO3 (111) were successfully obtained by using X-ray standing wave technique. Contributions of the Ti and SrO3 derived states to the valence-band spectra were clearly separated. The spectra provided not only site-specific but also bulk-sensitive information on the SrTiO3 crystal because of the use of a high-energy synchrotron X-ray source (hν=4750 eV) for photoelectron excitation with the large escape depth. The electronic structures calculated by the DV-Xα method using a (Sr8Ti27O108)92− cluster model well reproduced the observed structures in the valence-band spectra. The partial density of states of both Ti and Sr ions in SrTiO3 were mainly distributed over the bottom of the valence-band to produce the covalent bonding with O ions. 相似文献
76.
77.
Matsuta K. Minamisono T. Tanigaki M. Fukuda M. Nojiri Y. Mihara M. Onishi T. Yamaguchi T. Harada A. Sasaki M. Miyake T. Minamisono K. Fukao T. Sato K. Matsumoto Y. Ohtsubo T. Fukuda S. Momota S. Yoshida K. Ozawa A. Kobayashi T. Tanihata I. Alonso J. R. Krebs G. F. Symons T. J. M. 《Hyperfine Interactions》1996,97(1):519-526
The magnetic moments of the proton drip-line nuclei13O(I
= 3/2–,T
1/2 = 8.6 ms) and 9C(I
= 3/2–,T
1/2 = 126 ms) have been determined for the first time through the combined techniques of polarized radioactive nuclear beams and-NMR detection. The observed magnetic moments are ¦(13O)¦ = 1.3891 ±0.0003
N and ¦(9C)¦ = 1.3914 ±0.0005
N. Spin expectation values are deduced to be 0.76 and 1.44 for13O and9C, respectively. While the of13O is consistent with the systematics from isospinT= 1/2 mirror pairs, the of9C is unusually large, even far larger than the single particle value, = 1. 相似文献
78.
The extraction behavior of perrhenate with crown ethers was studied and methods for the separation and determination of rhenium were developed. The distribution ratio of perrhenate with dicyclohexano-18-crown-6 (DC18C6) increases with increases in the dielectric constant of organic solvents and in the potassium ion concentration of aqueous solution. The molar ratios of crown ether to KReO4 in the extracted species are probably 1:1 for DC18C6, dibenzo-18-crown-6 and 18-crown-6 and 2:1 for benzo-15-crown-5 and 15-crown-5. Microgram amounts of rhenium were satisfactorily separated from large amounts of molbdenum(VI) by extraction with DC18C6 in 1,2-dichloroethane from 2 M potassium hydroxide solution containing tartrate and by back-extraction with sodium phosphate buffer solution after the addition of a twofold volume of hexane to the organic phase. Rhenium was determined by the flow-injection extraction-photometric method with Brilliant Green. Rhenium was satisfactory determined in molybdenite and other ore samples. 相似文献
79.
Katsuma Hiraki Toshihiro Itoh Katsuya Eguchi Masayoshi Onishi 《Journal of organometallic chemistry》1983,241(1):C16-C20
Benzylchlorobis(triphenylphosphine)palladium(II) reacted with dimethyl acetylenedicarboxylate to give [Pd[C(CO2Me)=C(CH2Ph)(CO2Me)]Cl(PPh3)2] (II) and [(Ph3P)ClPdμ-C(CO2Me)=C(CO2Me)PdCl(PPh3) (III). Complexes II and III reacted with Tl(acac) to afford [PdC(CO2Me=C(CH2Ph)(CO2Me)-(acac)(PPh3)] and [(Ph3P)(acac)Pdμ-C(CO2Me)=C(CO2Me)Pd(acac)(PPh3)], respectively. 相似文献
80.
Nishioka T Onishi Y Nakajo K Guo-Xin J Tanaka R Kinoshita I 《Dalton transactions (Cambridge, England : 2003)》2005,(12):2130-2137
Thiacalix[3]pyridine (Py3S3) reacted with [Rh(diene)(mu-Cl)]2(diene = 1,5-cyclooctadiene (cod), 2,5-norbornadiene (nbd)) to give amphiphilic trigonal bipyramidal complexes, [Rh(Py3S3)(diene)]Cl. Sulfur bridges of the Py3S3 ligand in these complexes were selectively oxygenated by m-chloroperoxybenzoic acid in dichloromethane to give sulfinylcalix[3]pyridine complexes, [Rh(Py3(SO)3)(diene)]+, in which all three oxygen atoms of the SO groups occupy the equatorial positions. Structures of the complexes were analysed by X-ray crystallography and the oxidation reaction was investigated using 1H NMR spectroscopy and electrospray ionisation mass spectrometry showing that the oxygenation of the sulfur atoms in the ligand proceeded stepwise and further oxygenation of the SO moiety occurred only for the nbd complex having the smaller diene ligand resulting in [Rh(Py3(SO)2(SO2))(nbd)]+. On the other hand, the oxidation of [Rh(Py3S3)(cod)]+ by H2O2 in water did not result in oxygenation of the sulfur bridges but the cod ligand is hydroxygenated to give 1,4,5,6-eta4-2-hydroxycycloocta-4-ene-1,6-di-yl. 相似文献