Exploitation of New Catalytic Methods for the Construction of Carbon Frameworks and the Control of Reaction Fields

(1)在本项目启动之前，还没有关于高氧化态有机钚化学的系统研究。首次合成了几种新的含环戊二烯(CP)或五甲基环戊二烯(CP^*)配体的吡烯丙基Ru(IV)配合物。对具有代表性的Cp^*Ru(pi-烯丙基)Br2进行了X射线结构测定。详细研究了这些新的有机Ru(IV)化合物中碳-Ru(IV)键的化学反应活性的几个重要方面。元素有机金属反应的合理组合提供了基于Ru(II)-Ru(IV)氧化还原通道的新型高选择性催化剂。丁二烯或1，3-戊二烯在“CpRu^+”或“Cp^*Ru^+”型催化剂上进行线性齐聚反应。此外，丁二烯或异戊二烯在温和的条件下发生了环状二聚反应，得到了具有极高r…的相应的八元碳环骨架。“Cp^*Ru^+”催化剂具有更高的电子选择性和立体选择性。根据Cp~*Rux(Diene)/AgOTf与共轭双烯之间的一系列化学计量模型反应，阐明了Cp~*Rux(Diene)/AgOTf与共轭双烯反应的合理机理。(2)从铜(I)或Ru(II)配合物的单电子转移被发现是非常有效的氧化还原通道，通过分子内自由基加成形成C-C键。这一原始概念使化学计量自由基环化反应成为均相催化过程。以N-烯丙基三氯乙酰胺或三氯乙酸烯丙酯为原料，采用新的催化自由基环化反应合成三氯伽马内酰胺或内酯骨架。这些新方法被推广到一些连续的多步自由基环化反应，以及内酰胺或内酯骨架上双碳原子的不对称诱导。(3)设计并成功合成了全新的手性助剂--双恶唑烷基吡啶。它的Rh(III)络合物为对映选择性催化提供了一个三齿的子午型C2-手性反应场。较少

(1) There have been no systematic study on organoruthenium chemistry with high oxidation states until this project was started. Several new pi-allyl ruthenium(IV) complexes bearing cyclopentadinyl(Cp) or pentamethylcyclopentadienyl(Cp^*) ligands were successfully prepared in this project for the first time. The X-ray structure determination of the representative Cp^*Ru(pi-allyl)Br_2 was undertaken. Several important aspects on the chemical reactivity of the carbon-ruthenium(IV) bonds in these new organoruthenium(IV) compounds were investigated in detail. Judicious combinations of the elemental organometallic reactions provide new highly selective catalyses based on Ru(II)-Ru(IV) redox channel. Linear oligomerization of butadiene or 1,3-pentadiene proceeds with "CpRu^+" or "Cp^*Ru^+" type catalysts. Furthermore, a cyclic dimerization of butadiene or isoprene was found to take place under mild condition to give the corresponding eight-membered carbocyclic frameworks with extremely high r … More egio- and stereo-selectivity by means of "Cp^*Ru^+" catalyst. A reasonable mechanism was elucidated based on a number of stoichiometric model reactions between Cp^*RuX(diene)/AgOTf and the conjugated dienes.(2) Single electron transfer from Cu(I) or Ru(II) complexes was found to be extremely effective redox channel to the intramolecular radical addition to form C-C bonds. This original concept makes stoichiometric radical cyclizations to homogeneous catalytic processes. New catalytic radical cyclization was exploited for the construction of trichlorinated gamma-lactam or lactone skeletons starting from the appropriate acyclic precursors such as N-allyltrichloroacetamide or allyltrichloroacetate derivatives. These new methodologies were extended to some sequential multi-step radical cyclization, and to the asymmetric induction at the geminal carbon atoms on the lactam or lactone skeletons.(3) Completely novel chiral auxiliary, bis(oxazolinyl)pyridine, was designed and successfully synthesized. Its rhodium(III) complex provides a terdentate meridional C_2-chiral reaction field for enantioselective catalysis. Less