Peripheral Ruthenium(II) Complexes and Orthogonal, Ferrocyanide-Linked Bilayers of (β-Tetraethyl-β-p- and m-Tetrapyridyl)porphyrins in Bulk Water
| Autor: | Dan Donner, Ulrich Siggel, Christian Messerschmidt, Jürgen-Hinrich Fuhrhop, Christoph Böttcher |
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| Rok vydání: | 1999 |
| Předmět: | |
| Zdroj: | Langmuir. 15:5029-5039 |
| ISSN: | 1520-5827 0743-7463 |
| DOI: | 10.1021/la981791+ |
| Popis: | 2,8,12,18-Tetraethyl-3,9,13,17-tetra-m- and p-pyridylporphyrins have been synthesized via dipyrromethanes. They form strongly fluorescing planar monolayer leaflets in water. Upon titration with ferrocyanide the m-pyridylporphyrin adsorbs these anions and the fluorescence decreases drastically. One ferrocyanide ion quenches the fluorescence of about 50 porphyrin units. In the case of the p-isomer the quenching effect is much less pronounced. The zinc complex gives no defined monolayer in water, but assembles in the presence of equimolar amounts of ferrocyanide to a triple layer. Here, the central porphyrins are rotated into two different orthogonal positions: one of these porphyrin molecules provides its β-pyridyl groups as axial ligands of the central zinc ions for the outer layers, the other takes part in a closed hydrophobic region, in which the β-ethyl groups of two orthogonal porphyrin ligands interact. Transmission electron and atomic force microscopy were used to characterize this new type of molecular assembly. |
| Databáze: | OpenAIRE |
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