Analyzes and Designs of Local Electronic Structures of Molecules and Chemical Reactions

本研究的目的是通过实验化学家和理论家之间的讨论和密切合作，使理论更加完善和发展，以发现新的通用化学原理。现将迄今为止取得的结果概述如下。1.通过对Hartree-Fock分子轨道理论的修正，考察了π电子能量的物理意义和可加性。2.应用微扰理论，阐明了环戊二烯最高占据分子轨道的形变。环加成反应中的面选择性已根据轨道的形状进行了讨论。3.本文研究了β-取代碘鎓盐的溶剂分解机理。4.用密度泛函理论研究了正方平面铂（II）及其配合物的重排反应路径。除了能量和结构的计算，轨道相互作用，通过应用沃尔什图表明，一些适当选择的配体将提供稳定的四面体Pt（II）和Pd（II）的配合物，还没有发现到目前为止。5.以sp^3 C-H键的还原消除和活化为例，从头算Mo计算在揭示化学反应的分子机理方面已被证明是非常有用的。6.合成了含五甲基硫配体的钼和钨的硫配合物，并从电子能量观点研究了它们的簇合物和稳定性。7.具有扭曲π电子系统的八氢-4，4 '-联菲叉基产生光学活性对映体。理论计算所确定的对映体的立体化学经实验验证是正确的。

The purpose of this research is to make the theories more sophisticated and develop further to find out new principles in chemistry of general use through discussions and intimate cooperation between experimental chemists and theoreticians. The results so far obtained are summarized as follows. 1. By introducing a modification into the Hartree-Fock MO theory, the physical significance and the additivity of the pi electronic energy have been examined. 2. By applying the perturbation theory, the deformation of the highest occupied MO of cyclopentadiene has been clarified. The facial selectivity in cycloaddition has been discussed in terms of the shape of the orbital. 3. The mechanism of solvolysis in beta-substituted iodonium salts has been investigated. 4. The paths for the rearrangement of the square planar platinum (II) and related complexes have been studied by applying the density functional theory. In addition to the energy and structure calculations, orbital interactions by applying the Walsh diagram have indicated that some ligands chosen appropriately will provide stable tetrahedral Pt (II) and Pd (II) complexes that have not been found so far. 5. By taking reductive eliminations and activations of sp^3 C-H bonds as examples, ab initio Mo calculations have been demonstrated to be very useful in disclosing the molecular mechanisms of chemical reactions. 6. Sulfur complexes of molybdenum and tungsten having pentamethylcyclopentadienyl ligands have been synthesized and their clusters and stabilities have been studied from an electronic energy viewpoint. 7. Octahydro-4,4'-biphenanthrylidenes having twisted pi electron systems give optically active enantiomers. The stereochemistry of those enantiomers determined by theoretical calculations have been proved to be correct by experimental studies.