【摘要】 碳纳米管空腔不仅可以改变填充到其内部分子的性质,而且对其内部的SN2取代反应有促进或抑制作用,因而被视为一种新型的"固体溶剂".本文通过密度泛函理论研究了CH2O和PH3CH2在气相、苯溶液和碳纳米管空腔内的[2+2]加成反应.结果表明,与气相相比,碳纳米管空腔对于[2+2]环加成反应影响不大,这是因为所研究的[2+2]环加成反应中,反应物并不是轴对称的,不同于SN2取代反应的一维线性排列,所以具有较大轴向极化率的碳纳米管对[2+2]环加成反应影响较小.更多还原

【Abstract】 Recent studies have shown that the inner phase of carbon nanotubes (CNTs) can not only change the properties of molecules inside the tube,but also enhance or restrain the S N 2 reactions.Thus,the CNTs can be considered a form of solid solvent.In this paper,we study the [2+2] cycloaddition reaction between CH 2 O and PH 3 CH 2 in the gas phase,benzene solution and inner phase of CNT using the density functional theory (DFT).The results indicate that the inner phase of CNT has little effect on the [2+2] cycloaddition reaction.This can be explained as that while taking the linear arrangement for S N 2 reaction,the reactants do not possess the axial symmetry for the studied [2+2] cycloaddition reaction.Therefore,although the CNT has large axial polarizability,it can exert little influence on the [2+2] cycloaddition reaction.Our studies will be helpful for further understanding of the inner phase chemistry of CNTs.更多还原