Theoretical Study of Flexible Molecular Systems Possessing Complexed Electronic Structure Towards Reaction Design and Control

具有复杂电子结构的柔性分子体系对反应设计与控制的理论研究

• 批准号: 15350012
• 负责人: SAKAKI Shigeyoshi
• 金额: $ 9.09万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15350012/
• 关键词: Electronic Structure Theory; Transition Metal Complexes; Reaction Mechanism; Bonding Nature; Structure; Electron correlation effects; Reaction control; Function control; 混合原子価錯体; 錯体触媒反応; 遷移状態; 触媒サイクル; 電子状態制御; 遷移金属元素; 複合電子系; ヘテロ元素; 理論的研究

Theoretical Studies with electronic structure theory were carried out about hydrosilylation of alkene, hydrogenation of carbon dioxide, and Stille coupling reaction, which are typical transition-metal-catalyzed reaction. The hydrosilylation of alkene by Cp_2Zr takes place not only through alkene insertion into Zr-H bond but also coupling reaction between Zr-alkene species and hydrosilane. The product release step is not simple C-H and Si-C reductive elimination but alkene-assisted reductive eliminations and metathesis with hydrosilane. These differences from the late-transition-metal catalyzed hydrosilylation arise from the d orbital energy difference. Reaction mechanism of Ru-catalyzed hydrogenation of carbon dioxide was also theoretically elucidated in the presence of water molecule ; not the insertion of carbon dioxide into Ru-H but nucleophilic attack of hydride to carbon center of CO_2 takes place in the presence of water molecule, of which activation barrier is much smaller than usual CO_2 insertion. Stille coupling reaction takes place through oxidative addition of iodobenzene, transmetallation, and reductive elimination. Transmetallation is rate-determining step, which is accelerated by the presence of fluoride anion. The reason was discussed on the basis of bond energy.

运用电子结构理论对过渡金属催化的烯烃硅氢加成反应、二氧化碳加氢反应和Stille偶联反应进行了理论研究。Cp_2 Zr对烯烃的硅氢加成反应不仅通过烯烃插入Zr-H键进行，而且还通过Zr-烯烃物种与氢硅烷之间的偶联反应进行。产物的释放不是简单的C-H和Si-C还原消除，而是烯烃辅助的还原消除和与氢硅烷的复分解。这些差异从后过渡金属催化的氢化硅烷化产生的d轨道能量差。从理论上阐明了水分子存在下Ru催化CO_2加氢反应的机理，水分子存在下，CO_2不是插入Ru-H，而是氢化物亲核进攻CO_2的碳中心，其活化能垒比通常的CO_2插入小得多。Stille偶联反应通过碘苯的氧化加成、金属间化合物的转移和还原消除进行。硫代甲烷是速率决定步骤，氟离子的存在加速了该步骤。从键能角度分析了其原因。

项目成果

Theoretical Studies of C-H σ-Bond Activation and Related Reactions by Transition-metal Complexes

过渡金属配合物C-H σ键活化及相关反应的理论研究

• 发表时间: 2005
• 作者: Y.Kuramoto;N.Sawai;Y.Fujiwara;M.Sumimoto;Y.Nakao;H.Sato;S.Sakaki;S.Sakaki(他)
• 通讯作者: S.Sakaki(他)

Theoretical Study of Cp_2Zr-, (MeO)_2Zr-, and M(PH_3)-mediated Coupling Reactions of Acetylenes (M = Ni, Pt), Significant Differences between Early- and Late-Transition-Metal Complexes

Cp_2Zr-、(MeO)_2Zr-和M(PH_3)介导的乙炔(M = Ni、Pt)偶联反应的理论研究，早过渡金属配合物和晚过渡金属配合物之间的显着差异

• 发表时间: 2005
• 期刊: Organometallics 24(9)
• 作者: T.Imabayashi;Y.Fujiwara;Y.Nakao;H.Sato;S.Sakaki
• 通讯作者: S.Sakaki

Stabilization of Vinylidene-type and Acetylene-type Si2H2 Species by Coordination with Rhodium(I) and Platinum(O) Complexes. Theoretical Proposals

通过与铑 (I) 和铂 (O) 络合物配位稳定亚乙烯基型和乙炔型 Si2H2 物种。

• 发表时间: 2005
• 期刊: Organometallics 24
• 作者: Y.Kuramoto;N.Sawai;Y.Fujiwara;M.Sumimoto;Y.Nakao;H.Sato;S.Sakaki
• 通讯作者: S.Sakaki

Tamura, H., Yamazaki, H., Sato, H., Sakaki S.: "Iridium-Catalyzed Borylation of Benzene with Diboron. Theoretical Elucidation of Catalytic Cycle Including Unusual Iridium(V) Intermediates"J.Am.Chem.Soc.. 125. 16114-16126 (2003)

Tamura, H.、Yamazaki, H.、Sato, H.、Sakaki S.：“铱催化苯与二硼的硼化。包括不寻常铱 (V) 中间体的催化循环的理论阐明”J.Am.Chem.Soc。

Theoretical Study of Cp_2Zr-Catalyzed Hydrosilylation of Ethylene. Reaction Mechanism Including New σ-Bond Activation

Cp_2Zr 催化乙烯氢化硅烷化反应机理（包括新 σ 键活化）的理论研究。

• 发表时间: 2004
• 期刊: J.Am.Chem.Soc. 126
• 作者: S.Sakaki;T.Takayama;M.Sumimoto;M.Sugimoto
• 通讯作者: M.Sugimoto