Melville Laboratory for Polymer Synthesis, Department of Chemistry, University of Cambridge , Lensfield Road, Cambridge CB2 1EW, United Kingdom.
J Am Chem Soc. 2014 Jun 25;136(25):9053-60. doi: 10.1021/ja5032437. Epub 2014 Jun 17.
We report the self-assembly of a series of highly charged supramolecular complexes in aqueous media composed of cyclobis(4,4'-(1,4-phenylene)bispyridine-p-phenylene)tetrakis(chloride) (ExBox) and three dicationic perylene diimides (PDIs). Efficient energy transfer (ET) is observed between the host and guests. Additionally, we show that our hexacationic complexes are capable of further complexation with neutral cucurbit[7]uril (CB[7]), producing a 3-polypseudorotaxane via the self-assembly of orthogonal recognition moieties. ExBox serves as the central ring, complexing to the PDI core, while two CB[7]s behave as supramolecular stoppers, binding to the two outer quaternary ammonium motifs. The formation of the 3-polypseudorotaxane results in far superior photophysical properties of the central PDI unit relative to the binary complexes at stoichiometric ratios. Lastly, we also demonstrate the ability of our binary complexes to act as a highly selective chemosensing ensemble for the neurotransmitter melatonin.
我们报告了一系列在水溶液中自组装的高度荷电超分子复合物，它们由环双（4,4'-(1,4-亚苯基)双吡啶-p-亚苯基)四（氯化物）（ExBox）和三种二阳离子苝二酰亚胺（PDI）组成。在主体和客体之间观察到有效的能量转移（ET）。此外，我们表明我们的六阳离子配合物能够与中性瓜环[7]（CB[7]）进一步络合，通过正交识别部分的自组装产生 3 元假轮烷。ExBox 作为中环，与 PDI 核络合，而两个 CB[7]作为超分子止动器，结合到两个外部季铵盐图案上。假轮烷的形成导致中央 PDI 单元的光物理性质相对于化学计量比的二元复合物有了显著改善。最后，我们还证明了我们的二元配合物能够作为神经递质褪黑素的高选择性化学传感组件。
