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Updated: Dec 2, 2025
Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
Structure of a Dimeric BINOL-Imine-Zn(II) Complex and Its Role in Enantioselective Fluorescent Recognition
Kai Guo1, Ping Wang1, Wanli Tan1
1Key Laboratory of Medical Electrophysiology, Ministry of Education, School of Pharmacy of Southwest Medical University, Luzhou 646000, China.
Abstract:
A pyridine containing BINOL-based aldehyde (S)- or (R)-4 is found to show highly enantioselective fluorescent response toward phenylglycinol in the presence of Zn2+. A chirality matched dimeric BINOL-imine-Zn(II) complex is isolated from the reaction of (S)-4 with l-phenylglycinol and Zn2+ whose structure is established by X-ray analysis. Comparison of the structure of this SS-complex with a molecular modeling structure of the chirality mismatched SR-complex generated from the reaction of (S)-4 with d-phenylglycinol has provided important insight into the origin of the observed highly enantioselective fluorescent response. It is found that the solvent-accessible surface area of the chirality-matched SS-complex is much smaller than that of the chirality mismatched SR-complex, which gives the more tightly packed and structurally rigid SS-complex with greatly enhanced fluorescence.
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