Effective Coordination Control by Utilizing the Cavity of Calixarenes

利用杯芳烃空腔进行有效的配位控制

基本信息

批准号：
18550061
负责人：
ISHII Youichi
金额：
$ 2.71万
依托单位：
Chuo University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

项目摘要

Calixarenes are known to serve as a versatile ligand not only with two distinct types of coordination sites, phenolic oxygens and arene rings, but also with an inclusion site (cavity). However, coordination chemistry of transition-metal complexes inside the cavity of calixarenes still remains to be explored. In this study we have investigated two series of calix[4]arene complexes in which the metal centers are located inside the cavity of calix[4]arenes.The reaction of calix[4]arene with [CpRu(CH_3CN)_3]PF_6 in the presence of Et_3N has been found to give the ruthenium-arene type complex [CpRu{calix[4]-(0)(OH)_3}] (1)in good yield. An X-ray diffraction study of complex 1 has revealed that the CpRu+ fragment resides in the cavity of the calix[4]arene ligand, and the Cp protons of 1 exhibit characteristic high-field shift in the ^1H NMR. This fact makes a sharp contrast to the complexation of a Cp*Ru+ fragment with calix[4]arene where the metal center is bound at the outside face of a ph … More enolic ring(complex 2), and 1 can be viewed as a "self-inclusion" product. Further introduction of a Cp*Ru+ fragment into complex 1 gives rise to the inside-outside isomer of [(CpRu)(Cp*Ru){calix[4]-(0)(OH)_3}]+ (3), while introduction of a CpRu+ into 2 leads to its outside-outside isomer. These results indicates that the CpRu+ moiety is first coordinates at the outside face of a calixarene molecule, and then the ring inversion of the calixarene skeleton affords the inside coordination product.On the other hand, when [Ph_4P][ReO_2{p-tBu-calix[4]-(0)_4}] (4)is treated with a variety of cationic transition metal complex ML+, the phenoxo-bridged Re-M complexes [ReO_2{p-tBu-calix[4]-(0)_4}ML] (5a, ML = Cu(NCMe); 5b, Ag(Me2C0); 5c, Au(Ppha); 5d, Rh(cod)) can be obtained in good yield. The heterodinuclear core of complex 5a is located inside the cavity and have revealed to show unique spectral and chemical behaviors. For example, complex 5a undergoes selective alkyne incorporation, while complex 5d undergoes solvent-dependent isomerization to π-arene type regioisomers. Less

众所周知，杯芳烃是一种多功能配体，不仅具有两种不同类型的配位位点（酚氧和芳烃环），而且还具有包合物位点（空腔）。然而，杯芳烃空腔内的过渡金属配合物的配位化学仍然存在。在这项研究中，我们研究了两个系列的杯[4]芳烃配合物，其中金属中心位于杯[4]芳烃的空腔内。杯[4]芳烃与的反应。已发现在 Et_3N 存在下 [CpRu(CH_3CN)_3]PF_6 以良好的收率生成钌芳烃型络合物 [CpRu{calix[4]-(0)(OH)_3}] (1)。配合物 1 的 γ 射线衍射研究表明，CpRu+ 片段位于杯[4]芳烃配体的空腔中，并且 1 的 Cp 质子表现出特征^1H NMR 中的高场位移与 Cp*Ru+ 片段与 calix[4] 芳烃的络合形成鲜明对比，其中金属中心结合在 ph … More 烯醇环（络合物）的外表面上。 2)，并且1可以被视为“自包含”产物，进一步将Cp*Ru+片段引入复合物1中产生了内-外异构体。 [(CpRu)(Cp*Ru){calix[4]-(0)(OH)_3}]+ (3)，而将 CpRu+ 引入到 2 中会产生其外部-外部异构体。这些结果表明 CpRu+ 。部分首先在杯芳烃分子的外表面上配位，然后杯芳烃骨架的环反转提供内部配位产物。另一方面，当[Ph_4P][ReO_2{p-tBu-calix[4]-(0)_4}] (4)用多种阳离子过渡金属配合物ML+处理，得到苯氧桥接的Re-M配合物[ReO_2{p-tBu -calix[4]-(0)_4}ML] (5a, ML = Cu(NCMe); 5b, Ag(Me2C0); 5c, Au(Ppha); 5d, Rh(cod)) 可以以良好的产率获得，复合物 5a 的异双核核心位于空腔内，并显示出独特的光谱和化学行为，例如，复合物 5a 经历了选择性炔烃掺入。，而配合物 5d 则经历溶剂依赖性异构化为 π-芳烃型区域异构体。