d-pi Interaction in Transition Metal Cluster Complexes and Their Properties

过渡金属簇配合物中的 d-pi 相互作用及其性质

基本信息

批准号：
09650900
负责人：
KAWAMURA Takashi
金额：
$ 2.11万
依托单位：
GIFU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

Transition metal cluster complexes of rhodium and iridium with aromatic or chloro bridging ligands have been prepared, their structure and physicochemical properties have been studied and following results have been obtained.1. The reaction of dinuclear rhodium complexes with silyl chlorides gave new type of tetranuclear rhodium complexes with chloro-bridges.2. The symmetry and delocalization of the singly occupied molecular orbitals (SOMO) of rhodium dinuclear complexes were shown to be heavily dependent on ligands based on X-ray structures and DFT theoretical calculations. A large mixing ofsiguma_<RhRh> and n_p orbitals were observed for Rh_2^<5+> complexes with axial phosphine ligands. The pi_<RhRh>* orbital is localized on the metal atoms and the orbital is moderately delocalized onto the pi system of the bridging ligands.3. Diiridium complexes with bridging aminopyridine ligands were shown to have low oxidation potentials and short metal-metal separations.4. The delta* SOMO of Rh_2^<5+> complexes with hydroxypyridine ligands were shown to be delocalized onto the aromatic bridging ligands to the extent of about 10 %. In crystal, Rh_2^<4+> and Rh_2^<5+> complexes were packed with pi stacked arrangement of aromatic bridgeing ligands. Electric conductance of some of Rh_2^<5+> complexes were in the order of 10^<-7> S cm^<-1> (room temperature, pellets). Magnetism of crystals of Rh_2^<5+> complexes with aromatic bridging ligands were analyzed in relation to their crystal stucture.5. Square planar Pd(II) and Pt(II) complexes with silyl or stannyl and phosphine ligands showed facile twist-rotational unimolecular isomerization.

制备了铑、铱与芳香族或氯代桥连配体的过渡金属簇配合物，并对其结构和理化性质进行了研究，得到了以下结果： 1．双核铑配合物与氯硅烷反应得到新型氯桥四核铑配合物。 2．基于 X 射线结构和 DFT 理论计算，铑双核配合物的单占据分子轨道 (SOMO) 的对称性和离域性严重依赖于配体。对于具有轴向膦配体的Rh_2^<5+>配合物，观察到siguma_<RhRh>和n_p轨道的大量混合。 pi_<RhRh>*轨道定域于金属原子上，并且该轨道适度离域到桥配体的pi系统上。3．桥联氨基吡啶配体的二铱配合物具有较低的氧化电位和较短的金属-金属分离时间。 4．具有羟基吡啶配体的Rh_2^5+配合物的δ*SOMO显示出在芳香族桥连配体上离域至约10％的程度。在晶体中，Rh_2^<4+>和Rh_2^<5+>配合物由芳香桥配体的π堆叠排列堆积而成。一些Rh_2^5+复合物的电导率约为10^-7Scm^-1(室温，颗粒)。分析了Rh_2^<5+>芳香桥配体配合物晶体的磁性及其晶体结构。 5．具有甲硅烷基或甲锡烷基和膦配体的方形平面 Pd(II) 和 Pt(II) 配合物表现出容易的扭转-旋转单分子异构化。