Porphyrin-fullerene host-guest chemistry
Porphyrin-fullerene host-guest chemistry
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DOI：
10.1021/ja002214m
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发表时间：
2000-11-01
影响因子：
15
通讯作者：
Boyd, PDW
中科院分区：
文献类型：
--
作者：
Sun, DY;Tham, FS;Boyd, PDW
富勒烯自发地被卟啉和金属卟啉吸引。这种新的超分子识别元件首次在C60和C70与四芳基卟啉1 -3和八乙基金属卟啉的共晶中发现。4，5这些结构的一个自然特征是卟啉与夹在裂缝中的富勒烯的锯齿形排列。在计算中重现了这一现象，弯曲的π表面和平坦的π表面（富勒烯与卟啉的平面距离为货车）之间出人意料的强相互作用主要源于范德华力。2有了这些知识，我们已经使用分子建模来设计一个类似于颌骨的双卟啉，具有类似富勒烯大小的咬合力。图1中所示的钯连接的间吡啶基二聚体具有较高的计算的C60“气相”结合焓（约57 kcal·mol-1），表明溶液中富勒烯紧密结合。来自双齿络合的“螯合”效应也应该有贡献。当这项工作正在进行中时，据报道，一种双束缚的双卟啉与C60形成了1：1的复合物。[6]值得注意的是，结合常数（7× 105 M-1）超过了传统的凹型宿主，如杯芳烃、环三藜芦烯和间苯二酚。7
Fullerenes are spontaneously attracted to porphyrins and metalloporphyrins. This new supramolecular recognition element was first discovered in cocrystallates of C60 and C70 with tetraarylporphyrins1-3 and octaethylmetalloporphyrins. 4, 5 A natural feature of these structures is the zigzag arrangement of porphyrins with fullerenes sandwiched in the clefts. It is reproduced in calculations, and the unexpectedly strong interaction between a curved π surface and a flat π surface (Cfullerene-to-porphyrin plane distance∼ 2.7 Å) is largely van der Waals in origin. 2With this knowledge we have used molecular modeling to design a jaw-like bis-porphyrin with a similar fullerene-sized bite. The palladium-linked m-pyridyl dimer shown in Figure 1 has a high calculated “gas phase” binding enthalpy for C60 (∼ 57 kcal ‚mol-1) suggestive of tight fullerene binding in solution. A “chelate” effect from bidentate complexation should also contribute. While this work was in progress, a doubly strapped bisporphyrin was reported to form a 1: 1 complex with C60. 6 Notably, the binding constant (7× 105 M-1) exceeds those of traditional concave hosts such as calixarenes, cyclotriveratralenes, and resorcarenes. 7