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71.
Katsumi Katoh Shunsuke Ito Yusuke Wada Eiko Higashi Yasuhiro Suzuki Kazuhiro Kubota Katsuyuki Nakano Yuji Wada 《The Journal of chemical thermodynamics》2011,43(8):1229-1234
In this study, we examined the reaction hazard during the hydrosilylation reaction between trichlorosilane (TCS) and 1,6-divinyl(perfluorohexane) (FDV) in the presence of a butanol solution of chloroplatinic acid (Pt-Cat) as the catalyst. Assuming the three industrial risks of excessive addition of Pt-Cat, contamination by iron rust and mixing with cooling water, we observed the temperature and pressure change of TCS/FDV with an excessive amount of Pt-Cat, TCS/FDV/Pt-Cat with Fe2O3 and TCS/FDV/Pt-Cat with distilled water, using an accelerating rate calorimeter (ARC). The temperature and pressure greatly increased, especially in the sample with Fe2O3. For instance, in TCS/FDV/Pt-Cat with 1.5 wt.% Fe2O3, the heat release rate exceeded 624 K · min?1 and the pressure rose above 25 MPa during the exothermic reaction. 相似文献
72.
Anti-allergic effect of the flavonoid myricitrin from Myrica rubra leaf extracts in vitro and in vivo 总被引:1,自引:0,他引:1
Flavonoids are ingested by the general population as anti-oxidant and anti-inflammatory agents. In this study, we investigated the effects of myricitrin, a flavonoid rich in Myrica rubra leaf, upon anti-inflammatory action. Myrica rubra leaf extracts inhibited pro-inflammatory TNFα production in a macrophage cell line, Raw264.7 cells. We observed that the serum IgE levels in the leaf extract-treated DO11.10, a mouse allergy model, were down-regulated. HPLC was performed to demonstrate that M. rubra leaf extracts contain a large amount of myricitrin. We observed an inhibitory effect of HPLC-purified myricitrin on TNFα production in Raw264.7 cells. Thus, myricitrin may be of potential interest in the management of inflammatory conditions. 相似文献
73.
Bulky tertiary amines, especially dicyclohexylisobutylamine, smoothly reduced α,β-unsaturated ketones in the presence of trichlorosilyl triflate to give the corresponding saturated ketones in excellent yields. Isotope-labeling studies revealed that an α-hydrogen of the amine was transferred to the enones during reduction. 相似文献
74.
Copper-catalyzed benzylic C-H oxygenation under an oxygen atmosphere was developed starting from carbonitriles and Grignard reagents via N-H imine intermediates. The present process is characterized by the following two-step sequence in a one-pot manner: (1) addition of Grignard reagents to carbonitriles to form N-H imines and (2) benzylic C-H oxygenation (C═O bond formation) triggered by 1,5-hydrogen atom transfer with transient iminyl copper species. 相似文献
75.
Polymerization of 2-chloro-3-substituted thiophenes proceeded with a stoichiometric amount of magnesium amide, TMPMgCl·LiCl, or a combination of a Grignard reagent and a catalytic amount of secondary amine in the presence of a nickel catalyst. Although the nickel-catalyzed polymerization with NiCl(2)dppe, which exhibited high catalytic activity in the reaction of bromothiophenes, was less effective, use of a nickel catalyst bearing N-heterocyclic carbene as a ligand was found to induce polymerization with controlled molecular weight and molecular weight distribution. 相似文献
76.
Miyauchi M Li Y Yanai S Yotsugi K 《Chemical communications (Cambridge, England)》2011,47(30):8596-8598
A tungsten trioxide (WO(3)) coated aluminium (Al) substrate exhibits a reversible color change without light irradiation or an electric power supply. The sample turns blue upon exposure to an aqueous acid solution, but exposure to oxygen restores the original light yellow color. This color change is due to the galvanic redox reaction between WO(3) and Al. 相似文献
77.
Mason K Chang J Garlatti E Prescimone A Yoshii S Nojiri H Schnack J Tasker PA Carretta S Brechin EK 《Chemical communications (Cambridge, England)》2011,47(21):6018-6020
The use of "double-headed" phenolic oximes produces a trigonal antiprismatic [Fe(III)(3)](2) cluster with an "internal cavity" filled with an additional Fe(3+) ion. Magnetic measurements reveal that the competition between different exchange interactions leads to a low-spin ground multiplet weakly separated in energy from a complex pattern of low-lying excited levels. 相似文献
78.
Tanaka K Kukita K Ichibakase T Kotani S Nakajima M 《Chemical communications (Cambridge, England)》2011,47(19):5614-5616
Chiral lithium binaphtholate effectively catalyzed the enantioselective alkynylation of ketones using lithium acetylide as an alkynylating agent. This is the first example of the catalytic enantioselective addition of lithium acetylide to carbonyl compounds without the aid of other metal sources. 相似文献
79.
Watanabe R Fujiwara K Okazawa A Tanaka G Yoshii S Nojiri H Ishida T 《Chemical communications (Cambridge, England)》2011,47(7):2110-2112
The 4f-3d exchange couplings were definitively and precisely determined in the dinuclear complexes (Ln-M) involving double μ-oxo-bridges, by means of combined high-frequency electron paramagnetic resonance and pulsed-field magnetization techniques, revealing a monotonic decrease of ferromagnetic J(Ln-Cu) in the order of the atomic number, (64)Gd to (68)Er. 相似文献
80.