Site-Selective and Stepwise Complexation of Transition Metal Fragments on Calixarene and Functions of Polynuclear Calixarene Complexes

尽管最近对杯芳烃的兴趣很大，但对未改性杯芳烃的后过渡金属络合物知之甚少。本研究发展了7-10族过渡金属杯芳烃衍生物的合成方法，并揭示了它们独特的反应活性。对于杯芳烃第9族金属配合物，[（cod）M（Ome）]2（M = Rh，Ir）与杯[4]芳烃（LH_4）的摩尔比为0.5-0.6：1时，可得到铑芳烃配合物[（cod）M（LH_3）]，而当摩尔比为1.1-1.5：1时，可得到铑芳烃配合物[（cod）M（LH_3）]。1（M = Rh）导致选择性地形成双核配合物[{（cod）Rh}2（LH 2）]，其中Rh（cod）+一个片段由芳基配位，另一个片段由两个酚氧原子配位。后者的配合物的铑-铱杂环类似物的逐步合成也已实现。另一方面，通过用[Ph 4P][ReOCl 4]处理LHLi 3，然后用Ag 2 O氧化来合成阴离子二氧铼络合物[Ph 4P][ReO 2L]（LH 4 = p-tBu-杯[4]芳烃）。[Ph 4P][ReO 2L]是第一个金属原子直接与杯芳烃体结合的杯芳烃双金属配合物。更重要的是，[Ph 4P][ReO 2L]与溶剂化阳离子[Pd（C3 H5）（Me 2CO）x]+和[Rh（nbd）（Me 2CO）x]+反应，分别得到了[ReO 2LPd（C3 H5）]和[ReO 2LRh（nbd）]。后一种配合物提供了双核杯芳烃配合物的第一个例子，其在杯芳烃配体的空腔内具有异双核过渡金属核。

In spite of the recent interest in metallocalixarenes little is known for late transition metal complexes of unmodified calixarenes. In this study we have developed the synthetic methods for group 7-10 transition metal derivatives of calixarenes and revealed their unique reactivities. As for the calixarene group 9 metal complexes, the reaction of [(cod)M(Ome)]2 (M = Rh, Ir) with calix[4]arenes (LH4) in the molar ratio of 0.5-0.6: 1 has been found to give the rhodium arene complexes [(cod)M(LH3)], while that in the molar ratio of 1.1-1.5:1(M = Rh) leads to the selective formation of the dinuclear complexes [{(cod)Rh}2(LH2)] in which one of the Rh(cod)+ fragments is coordinated by an aryl group and the other by two phenolic oxygen atoms. The stepwise synthesis of the Rh-Ir heterobimetallic analogue of the latter complex has also been achieved. On the other hand, the anionic dioxorhenium complex [Ph4P][ReO2L] (LH4 = p-tBu-calix[4]arene) is synthesized by treatment of LHLi3 with [Ph4P][ReOCI4] followed by oxidation with Ag2O. [Ph4P][ReO2L] is the first calixarene rhenium complex in which the metal atom is directly bound to the body of calixarene. More importantly, [Ph4P][ReO2L] reacts with solvated cationic species [Pd(C3H5)(Me2CO)x]+ and [Rh(nbd)(Me2CO)x]+ to afford the heterobimetallic complexes [ReO2LPd(C3H5)] and [ReO2LRh(nbd)], respectively. The latter complexes provide the first examples of dinucelar calixarene complexes which possess a heterodinuclear transition metal core inside the cavity of a calixarene ligand.