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排序方式: 共有95条查询结果,搜索用时 15 毫秒
91.
Yoshisuke Futami Satoshi Kudoh Fumiyuki Ito Taisuke Nakanaga Munetaka Nakata 《Journal of Molecular Structure》2004,690(1-3):9-16
The CH3Cl and CH3Br dimers produced by supersonic-jet expansion were directly deposited on a cold plate using a standard matrix-isolation technique. Dependence of the relative intensities of the observed infrared bands on the stagnation pressure was used to assign the dimer bands appearing near the monomer bands. By a comparison of the wavenumber shifts from the monomer bands with the corresponding values obtained by quantum chemical calculations, DFT/B3LYP/6-311++G(3pd,3df) and MP2/LanL2DZ+fdp, the structures of CH3Cl and CH3Br dimers were determined to be a head-to-tail isomer, which is common to the CH3F and CH3I dimers determined previously by the same method. The remaining dimer bands, which could not be assigned to the head-to-tail isomer, were tentatively assigned to a head-to-head isomer in analogy with CH3I dimer. 相似文献
92.
Minami T Okamoto H Ikeda S Tanaka R Ozawa F Yoshifuji M 《Angewandte Chemie (International ed. in English)》2001,40(23):4501-4503
93.
Nakajima Y Shiraishi Y Tsuchimoto T Ozawa F 《Chemical communications (Cambridge, England)》2011,47(22):6332-6334
Cu(I) complexes bearing BPEP as a PNP-pincer type phosphaalkene ligand undergo effective bonding interactions with SbF(6)(-) and PF(6)(-) as non-coordinating anions to give [Cu(SbF(6))(BPEP)] and [Cu(2)(BPEP)(2)(μ-PF(6))](+), respectively [BPEP = 2,6-bis(1-phenyl-2-phosphaethenyl)pyridine]. NMR and theoretical studies indicate a reduced anionic charge of the μ-PF(6) ligand, which is induced by the strong π-accepting ability of BPEP. 相似文献
94.
The preparation and characterization of sterically protected diphosphinidenecyclobutenes bearing two two-coordinate phosphorus atoms are described from the viewpoint of the development of a novel type of bidentate ligand for transition-metal complexes. They form complexes with group 6 metals such as chromium, molybdenum and tungsten, group 8 metals such as ruthenium, group 10 metals such as palladium and platinum, and group 11 metals such as copper and gold. Some of them can be used as catalysts for synthetic reactions such as cross-coupling of the Sonogashira type, Suzuki-Miyaura coupling, Ullmann coupling, Kosugi-Migita-Stille coupling, cyanation, polymerization of ethylene, dehydrogenative hydrosilylation of ketones, hydroamination of 1,3-butadienes, and direct alkylation or amination of allylic alcohols of Tsuji-Trost reactions. 相似文献
95.
In vitro leishmanicidal constituents of Millettia pendula 总被引:2,自引:0,他引:2
Takahashi M Fuchino H Sekita S Satake M Kiuchi F 《Chemical & pharmaceutical bulletin》2006,54(6):915-917
The in vitro leishmanicidal constituents of Millettia pendula were examined. Two new compounds, 1 (millettilone A) and 2 (millettilone B), were isolated from the methanol extract of M. pendula, together with six known compounds: 3R-claussequinone (3), pendulone (4), secundiflorol I (5), 3,8-dihydroxy-9-methoxypterocarpan (6), 3,10-dihydroxy-7,9-dimethoxypterocarpan (7), and formononetin (8). Among these, pendulone showed the most potent leishmanicidal activity. Compound 2 was found to be a purple pigment in this heartwood. Their chemical structures were elucidated using spectral methods. 相似文献