| Abstrakt: |
1,3‐Dipyrrolyl‐1,3‐propanediones, synthesized from pyrroles and malonyl chloride, form BF2complexes, which represent a new class of naked‐eye sensors for halide and oxoanions. The association mode for the interactions of both the pyrrolyl NH and bridging CH protons with anions was confirmed by 1H NMR chemical shifts in CD2Cl2and supported by theoretical studies. The binding constants (Ka) were estimated as 8.1×104, 2.0×103, 3.3×102, 1.3×104, and 80m−1for F−, Cl−, Br−, H2PO4−, and HSO4−by UV/Vis absorption spectral changes in CH2Cl2. Augmentation of Kacompared with dipyrrolylquinoxaline for H2PO4−is much larger than those for other anions. Contrary to other anions, F−quenches the emission almost completely, which was detected by the fluorescence spectrum as well as the naked‐eye. In the case of the chloride anion complex, the formation of Cl−‐bridged 1D networks, in which anion is associated with two BF2complexes, is observed in the solid state. |
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