Molecular acrobatics: Self-assembly of calixarene-porphyrin cages
Molecular acrobatics: Self-assembly of calixarene-porphyrin cages
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DOI：
10.1021/ja036758a
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发表时间：
2003-11-19
影响因子：
15
通讯作者：
Ungaro, R
中科院分区：
文献类型：
--
作者：
Baldini, L;Ballester, P;Ungaro, R
已经制备了两个和四个锌卟啉的杯[4]芳烃，它们与双齿配体DABCO的自组装性能表现出显著的灵活性。杯-双卟啉与DABCO形成2：2的络合物，形成一个很大的空腔，有可能作为超分子宿主。另一方面，根据化学计量比和浓度的不同，杯四卟啉与DABCO形成四种不同的络合物。在滴定过程中，所有四个络合物都被填充，导致了大的构象变化，形成了分子内和分子间的杯-四卟啉-DABCO夹心络合物。用紫外-可见光谱和核磁共振氢谱对该体系进行了充分的表征。当杯-四-卟啉：DABCO的比例为2：4时，主要的物种是二聚体笼状组装，其特征是有一个大的内腔供客体络合。
Calix[4]arenes equipped with two and four zinc porphyrins have been prepared, and they show remarkable flexibility in their self-assembly properties with the bidentate ligand DABCO. The calix-bisporphyrin forms a 2:2 complex with DABCO, generating a large cavity that has the potential to act as a supramolecular host. The calix-tetraporphyrin, on the other hand, forms four different complexes with DABCO depending on the stoichiometry and concentration. During the course of a titration, all four complexes are populated, leading to large conformational changes and the formation of both intramolecular and intermolecular calix-tetraporphyrin-DABCO sandwich complexes. The system was fully characterized using a combination of UV-visible and H-1 NMR spectroscopy to identify the complexes. At a calix-tetraporphyrin: DABCO ratio of 2:4, the major species is dimeric cage assembly that features a large internal cavity for guest complexation.