Binding Studies of a Luminescent Pt(II) Organometallic Calix[4]pyrrole with Halide Salts
We report the synthesis of a luminescent Pt(II) complex, PtL2, based on a “two-wall” aryl-extended calix[4]pyrrole (C[4]P). We characterize its binding properties as a receptor of methyl trioctyl ammonium chloride (MTOA·Cl) in a dichloromethane solution. To this end, we performed 1H NMR and UV−vis s...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 2025 |
| País: | España |
| Institución: | Universidad de Barcelona |
| Repositorio: | Dipòsit Digital de la UB |
| OAI Identifier: | oai:diposit.ub.edu:2445/228317 |
| Acceso en línea: | https://hdl.handle.net/2445/228317 |
| Access Level: | acceso abierto |
| Palabra clave: | Compostos organometàl·lics Compostos d'halògens Química organometàl·lica Organometallic compounds Halogen compounds Organometallic chemistry |
| Sumario: | We report the synthesis of a luminescent Pt(II) complex, PtL2, based on a “two-wall” aryl-extended calix[4]pyrrole (C[4]P). We characterize its binding properties as a receptor of methyl trioctyl ammonium chloride (MTOA·Cl) in a dichloromethane solution. To this end, we performed 1H NMR and UV−vis spectroscopic titrations. The singular luminescent properties of PtL2 allowed the use of highly sensitive emission spectroscopy to</p><p>monitor the binding. The binding affinity of PtL2 for MTOA·Cl is 2-fold smaller than that of the C[4]P precursor. This difference is attributed to dissimilar anion−π interactions and binding geometries in the ion-paired complexes of the two receptors, (Cl⊂PtL2/C[4]P)@MTOA. Isothermal titration calorimetry (ITC) experiments revealed subtle differences in enthalpy and entropy. The entropic term, although negative, was very small, suggesting the relevance of the dissociation/association processes of the salt and the ion-paired complexes. We investigated the binding selectivity of PtL2 toward a series of halides in acetone solution favoring ion-pair dissociation. PtL2 binds chloride selectively and with a high affinity, producing mainly an anionic complex. |
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