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The practical synthesis procedure of substituted tetraphenylene derivatives involving the synthesis of a precursor for 4, 7-dunethoxyisobenzofuran and Diets-Alder addition of 4, 7-dimethoxyisobenzofuran generated in situ to 5, 6, 11,12-te-tradehydrodibenzo[a,e]cyclooctene, followed by a low valent titanium mediated deoxygenation to give 1,4, 11, 14-tetra-methoxy-dibenzo[b, n] tetraphenylene, which can be further demethyiated to the corresponding phenolic compound, which was acetylated to afford 1,4,11,14-tetraacetoxy-dibenzo-[ b, n] tetraphenylene. 相似文献
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Kinetic calculation for the reaction of H with Si_2H_6 using the variational transition state theory
The reaction of disilane with atomic hydrogen has been studied. This reaction involves both substitution and abstraction. Calculations show that the hydrogen abstraction is the strongest competing channel. The canonical variational transition state theory with a small curvature tunneling correction (SCT) has been used for the kinetic calculation. The theoretical results are in good agreement with the available experimental data. Comparing the reactions of atomic hydrogen with disilane and silane, it can be seen that the reactivity of the Si-H bond is higher in Si2H6than that in SiH4. 相似文献
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TrichlorosilaneisanimportantmaterialinplasmaChemicalVaporDeposition (CVD)andinsemiconductordeviceprocess .1 4 Thereactionoftrichlorosilanewithatomichydrogen ,thesimplestfree radicalspecies,hasdrawnconsiderableattention :kineticparametersforH atomreactionared… 相似文献
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F+CH2CO的反应机理和动力学研究 总被引:7,自引:0,他引:7
用G3(MP2)方法对F与CH2CO的反应进行研究,揭示了该反应的加成-消除机理.F原子首先与CH2CO作用形成富能的中间体CH2FCO*,此加成反应为无势垒过程.富能的CH2FCO*可进一步发生解离或异构化反应生成各种可能的产物.其中CO和CH2F可能为反应的主要产物.根据从头算的结果,用RRKM-TST理论计算该反应的速率常数.总包反应速率常数与温度存在弱的依赖关系,与总压力无关. 相似文献
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CH_3SGN与O_2气相反应机理的理论研究 总被引:1,自引:1,他引:0
在G3(MP2)水平上,通过对CH_3S与O_2rcyi2rvylce dm (PES)上关键驻点的能 量计算,共找到4种中间体,9个过渡态,6种产物通道,并对这些气相反应机理进 行了讨论,同时应用TST-RRKM理论对主要反应的速率进行计算。结果表明:CH_3S 与O_2反应在低温下以生成CH_3SOO为主,并与实验结果吻合;在中高温下以消去和 抽提反应为主,分别生成CH_3 + SO_2和CH_2S + HO_2,其它产物较少。 相似文献