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This content will become publicly available on March 29, 2023

Title: Synthesis of bright water-soluble circularly polarized luminescence emitters as potential sensors
We describe the synthesis of C 2 -symmetrical enantiopure lanthanide complexes (Tb, Eu, Sm, Dy) supported by the decadentate ligand N , N , N ′, N ′-tetrakis[(6-carboxypyridin-2-yl)methyl]-1,2-diaminocyclohexane (tpadac). The chiral tpadac ligand was designed to protect the lanthanide center from coordination of inner-sphere water molecules resulting in air- and water-stable, and highly luminescent complexes in water. The complexes exhibit strong chiroptical properties, with high dissymmetry factors g lum (0.11 to 0.25) and CPL brightness B CPL (up to 245 M −1 cm −1 for Tb, λ exc 295 nm, λ em 544 nm) in water. These are the first example of aqueous Sm CPL and second example of aqueous Dy CPL reported to date. The lanthanide complexes obtained gave a reversible CPL response to pH ranging from 6.0 to 8.0. In addition, distinctive CPL responses (including a change in CPL sign) towards toxic cations (Pb 2+ , Cd 2+ , and Mn 2+ ) were also observed, demonstrating the potential of our complexes to be used as aqueous probes.
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Inorganic Chemistry Frontiers
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1474 to 1480
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National Science Foundation
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