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191.
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   
192.
[3]Rotaxane containing two Pd centers in the cyclic compounds catalyzes a Mizoroki-Heck reaction of substrates with two iodophenyl groups with bisacrylate. Formation of the cyclic products is enhanced by the rotaxane catalyst more smoothly than Pd(OAc)(2).  相似文献   
193.
A method for oligoarene synthesis involving chemoselective cross-coupling as the key reaction was developed. Boronic acids with a chloro or trifluoromethanesulfonyloxy group were used as the monomer precursors with either of two chemoselective catalytic systems: Pd with P(t-Bu)(3), and Pd with 1,1'-bis(diphenylphosphino)ferrocene (DPPF). This method enabled elongation by one benzene unit in every step and thus reduced the number of steps required for elongation of oligoarene chains with well-defined lengths and sequences of substituted benzene rings.  相似文献   
194.
Ito Y  Takahashi K  Nagase H  Honda T 《Organic letters》2011,13(17):4640-4643
A novel synthetic path to sequosempervirin A was established by employing a samarium diiodide promoted intramolecular Barbier-type reaction of the lactonic iodide, in which the key structural feature, a spiro[4.5]decane ring system, could be constructed by controlling the stereochemistry of the hydroxyl group at the 8-position. The absolute configuration of natural sequosempervirin A was revised to be 4S based on this synthesis.  相似文献   
195.
Two polyoxometalate assemblies, TBA(9)[{γ-H(2)SiW(10)O(36)Al(2)(μ-OH)(2)(μ-OH)}(3)] (1; TBA = tetra-n-butylammonium) and TBA(6)Li(3)[{γ-H(2)SiW(10)O(36)Al(2)(μ-OH)(2)(μ-OH)}(3)]·18H(2)O (2), were synthesized by trimerization of a dialuminum-substituted silicotungstate monomer. Both 1 and 2 possessed a layered structure composed of a basal sheet unit [TBA(3){γ-H(2)SiW(10)O(36)Al(2)(μ-OH)(2)(μ-OH)}(3)](6-) and interlayer cations. The interconversion between 1 and 2 reversibly took place through interlayer cation exchange.  相似文献   
196.
Soluble copper phthalocyanine (CuPc) and naphthalocyanine (CuNc) precursors which can be converted thermally and photochemically into insoluble CuPc and CuNc, respectively, have been synthesized by a one-step reaction using commercially available chemicals.  相似文献   
197.
198.
Terminal-acetylated hyperbranched poly(ethylene glycol) derivatives containing diethylene, triethylene, and hexaethylene and 3,5-dioxybenzoate branching units (poly-Ac1a, poly-Ac1b, and poly-Ac1c) were synthesized. Electrochemical and thermal properties of the hyperbranched polymer electrolytes with lithium salts such as LiCF3SO3 and LiN(CF3SO2)2, the composite hyperbranched polymer electrolytes with LiN(CF3SO2)2 containing α-LiAlO2 and γ-LiAlO2 fillers, and the hyperbranched polymer blended poly(ethylene oxide) electrolytes with LiN(CF3SO2)2 were investigated and discussed. Paper presented at the 8th EuroConference on Ionics, Carvoeire, Algarve, Portugal, Sept. 16–22, 2001.  相似文献   
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200.
In this study, we show that earnings forecasting creates an index-tracking portfolio that dominates the historical model trade-off curve. We find that using Toyo Keizai earnings forecasts improves geometric means by over 300 basis points compared to the historical model. Weighted latent root regression is used in this study to create portfolios that have outperformed the Japanese market in backtest and in real-time performance.  相似文献   
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