The Construction of Homochiral Lanthanide Quadruple-Stranded Helicates with Multiresponsive Sensing Properties toward Fluoride Anions.

A series of unique homochiral lanthanide tetranuclear quadruple-stranded helicates have been self-assembled controllably by using the intrinsic advantages of chiral bridging ligands, (S)-H2 L and (R)-H2 L, and lanthanide ions with high coordination numbers. The self-assembly process of these chiral helicates not only ensures the structural stability and quadruple-stranded feature of lanthanide cluster in the solid state and solution, but also achieves effective transfer and amplification of the chirality code from the ligand to a higher supramolecular level. Moreover, through using optical rotation, circular dichroism spectra analysis, and luminescence measurements, we demonstrate that these chiral lanthanide helicates could serve as sensitive and multi-responsive sensors to recognize and detect F- anions based on the change of chiral signal and NIR luminescence simultaneously, which represents a meaningful exploration for developing functional lanthanide-based polynuclear clusters.