Homochiral Dodecanuclear Lanthanide “Cage in Cage” for Enantioselective Separation Academic Article uri icon

abstract

  • It is extremely difficult to anticipate the structure and the stereochemistry of a complex, particularly when the ligand is flexible and the metal node adopts diverse coordination numbers. When trivalent lanthanides (LnIII) and enantiopure amino acid ligands are utilized as building blocks, self-assembly sometimes yields rare chiral polynuclear structures. In this study, an enantiopure carboxyl-functionalized amino acid-based ligand with C3 symmetry reacts with lanthanum cations to give a homochiral porous coordination cage, (Δ/Λ)12-PCC-57. The dodecanuclear lanthanide cage has an unprecedented octahedral "cage-in-cage" framework. During the self-assembly, the chirality is transferred from the enantiopure ligand and fixed by the binuclear lanthanide cluster to give 12 metal centers that have either Δ or Λ homochiral stereochemistry. The cage exhibits excellent enantioselective separation of racemic alcohols, 2,3-dihydroquinazolinones, and multiple commercially available drugs. This finding exhibits a rare example of a multinuclear lanthanide complex with a dual-walled topology and homochirality. The highly ordered self-assembly and self-sorting of flexible amino acids and lanthanides shed light on the chiral transformation between different complicated artificial systems that mimic natural enzymes.

author list (cited authors)

  • Zhu, C., Tang, H., Yang, K., Fang, Y. u., Wang, K., Xiao, Z., ... Zhou, H.

complete list of authors

  • Zhu, Chengfeng||Tang, Haitong||Yang, Keke||Fang, Yu||Wang, Kun-Yu||Xiao, Zhifeng||Wu, Xiang||Li, Yougui||Powell, Joshua A||Zhou, Hong-Cai

publication date

  • January 1, 2021 11:11 AM