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11.
Hiroyuki Higuchi Kazuhiro Takatsu Tetsuo Otsubo Yoshiteru Sakata Soichi Misumi 《Tetrahedron letters》1982,23(6):671-672
A novel cage compound was obtained by irradiation of a quadruple-layered dithiacyclophane and showed thermally reverse reaction. 相似文献
12.
On treatment of the 2-allyl-3-aminocyclohexenones with mercury(II) acetate, either sequence, dehydrogenation—oxymercuration or dehydrogenation—aminomercuration, occurred depending on the nature of the amino group in the substrate to yield the dihydrobenzofurans or indoles, respectively. 相似文献
13.
Iwao Ojima Shin-Ichi Inaba Tetsuo Kogure Makoto Matsumoto Hideyuki Matsumoto Hamao Watanabe Yoichiro Nagai 《Journal of organometallic chemistry》1973,55(1):C4-C6
[RhCl(PPh3)3] is a very effective catalyst for the cleavage of Si-Si bonds by alcohols. 相似文献
14.
Tetsuo Hiramoto Masanobu Nishii Vladimir Fiala Hitoshi Yamaoka 《Journal of polymer science. Part A, Polymer chemistry》1973,11(9):2257-2263
Radiation-induced solid-state polymerization of cyclohexene sulfide has been investigated. Differential thermal analysis shows that this compound has a phase transition point at ?74°C and behaves as a plastic crystal in the temperature range from ?74 to ?20°C (melting point). By rapid cooling, this plastic crystal was easily supercooled, and below ?166°C a glassy crystal, i.e., a supercooled nonequilibrium state of plastic crystal, was obtained. In-source polymerization proceeded in the plastic crystalline state. Postpolymerization of glassy crystalline monomer irradiated at ?196°C occurred above ?166°C (glass transition point) during subsequent heating. 相似文献
15.
The Longuet-Higgins and Pople type SCF MO theory was applied to the all-valence-electron systems of several -type radicals and their g-tensors were theoretically calculated with the Stone's equation. Principal values or diagonalyzed g-tensors were obtained and compared with experimental values in ESR spectra. 相似文献
16.
Fumio Hamada Kyoko Ishikawa Riko Ito Hisanori Shibuya Sanyo Hamai Iwao Suzuki Tetsuo Osa Akihiko Ueno 《Journal of inclusion phenomena and macrocyclic chemistry》1994,20(1):43-51
-Cyclodextrin with two sodium anthranilate moieties (1) has been prepared as a sensor for detecting organic compounds including terpenoids and steroids. Compound1 shows a pure monomer fluorescence whose intensity is increased or decreased upon addition of the guest species examined. In this system, the sodium anthranilate moieties act either as a spacer, which enables the cyclodextrin to form a 1:1 host-guest complex by narrowing the -cyclodextrin cavity, or as a hydrophobic cap.1 recognizes steroids with much higher sensitivity than terpenoids, in which the appended moieties act as a hydrophobic cap for terpenoids and a spacer for steroids, respectively. 相似文献
17.
Susumu Narita Takeshi Hamakawa Tetsuo Morikawa Tai-ichi Shibuya 《Monatshefte für Chemie / Chemical Monthly》2002,133(7):987-990
Summary. The generalized Pauling bond order was enumerated in the C60 fullerene cage molecule (truncated icosahedral symmetry). This index measures chemical similarity in fullerene derivatives
such as dihydrofullerene (C60H2), anionized monohydrofullerene (C60H−), N-substituted monohydrofullerene (C59NH), the fullerene dimer ((C60)2), and the dianionic fullerene dimer ((C60)2
2−). It is also useful in judging the chemical stability of isomers.
Received October 9, 2001. Accepted November 9, 2001 相似文献
18.
Jun-Ichi Anzai Yoko Sakata Yasuhiro Suzuki Akihiko Ueno Tetsuo Osa 《Journal of polymer science. Part A, Polymer chemistry》1983,21(3):855-864
Crown ether-modified polyethylenimines (PEI-CR) were prepared to elucidate their cation binding efficiency and selectivity by liquid-liquid and solid-liquid extraction methods. With alkali metal cations it was found that polyethylenimines containing benzo-15-crown-5 moieties (Ia and Ib) extracted all cations examined more efficiently than their monomeric analogs, especially in the cases of K+ and Rb+ cations. The solid-liquid extraction revealed clearly that the polymers complexed with K+ and Rb+ cations according to a 1:2 cation-to-crown stoichiometry. The high selectivities of the polymers for K+ and Rb+ were interpreted in terms of the favourable conformation of the polymer chain for the formation of intramolecular 1:2 complexes. On the contrary, these polymers bound alkali earth cations less effectively with low selectivities. 相似文献
19.
Homogeneous palladium catalyst suppressing Pd black formation in air oxidation of alcohols 总被引:1,自引:0,他引:1
Iwasawa T Tokunaga M Obora Y Tsuji Y 《Journal of the American Chemical Society》2004,126(21):6554-6555
In homogeneous catalyst systems, there is the persistent problem that metal aggregation and precipitation cause catalyst decomposition and considerable loss of catalytic activity. Pd black formation is a typical example. Pd catalysts are known to easily aggregate and form Pd black, although they realize a wide variety of useful reactions in organic synthesis. In order to overcome this intrinsic problem of homogeneous Pd catalysis, we explored a new class of Pd catalyst by adopting aerobic oxidation of alcohols as a probe reaction. Herein we report a new catalyst system that suppresses the Pd black formation even under air and with a high substrate to catalyst molar ratio (S/C: more than 1000) in oxidation of alcohols. The novel pyridine derivatives having a 2,3,4,5-tetraphenylphenyl substituent and its higher dendritic unit at the 3-position of the pyridine ring were found to be excellent ligands with Pd(OAc)2 in the palladium-catalyzed air (balloon) oxidation of alcohols in toluene at 80 degrees C. Comparison with structurally related pyridine ligands revealed that introduction of the 2,3,4,5-tetraphenylphenyl substituent at the 3-position of pyridine ring effectively suppresses the Pd black formation, maintaining the catalytic activity for a long time to give aldehydes or ketones as products in high yields. 相似文献
20.
Tetsuo Miyazaki Shigeru Nagasaka Isao Maeda Takuro Matsumoto Shinji Koyama Seiji Kodama Masami Watanabe 《Radiation Physics and Chemistry》1996,47(6):817-819
Emission from high-energy-electron-irradiated golden hamster embryo (GHE) cells has been studied over the temperature range 12–300 K both by a one-shot-single-photon-counting method and by photocurrent measurements with an oscilloscope. Emission from the irradiated phosphate buffered saline (PBS) also has been studied. The emission spectra from PBS at 12 and 77 K show a maximum around 330 and 380 nm, respectively, which are the same spectra as those from irradiated pure H2O. The emission from irradiated GHE consists of the new band at 480 nm in addition to the emission from H2O. The 480 nm emission is observed at the temperature range of 12–300 K, though the emission at 300 K is much lower than that at low temperature. The 480 nm emission is ascribed to the transition from excited organic substances in GHE cells. The intensity of 480 nm emission at 300 K increases linearly with increasing irradiation-dose in the range of 11–600 Gy. 相似文献