Helicity adaptation within a quadruply stranded helicate by encapsulation

Abstract

The helical chirality can be tuned by both the size and number of anion guests.

Balancing Ligand Flexibility versus Rigidity for the Stepwise Self‐Assembly of M12L24 via M6L12 Metal–Organic Cages

“…This motif has been widely used for the development of aromatic oligoamide foldamers with highly predictable and stable structures . For metal based self‐assembly, ligands of this type have been used for the formation of small Pd 2 L 4 cages but never been shown to be applicable for larger structures . As the above interactions should limit the flexibility of the bend angle, we reasoned that large cages could be accessible.…”

A Charge-Neutral Self-Assembled L2Zn2 Helicate as Bench-Stable Receptor for Anion Recognition at Nanomolar Concentration

“…The final assembly of the receptor is conducted by metal coordination which generally proceeds in a quantitative manner and does not require the use of suitable templates often seen, e.g., in organic macrocyclization reactions. An overwhelming number of helicates and lantern-shaped metallacages with the ability to encapsulate different anions have been reported in the last two decades − since the pioneering work of McMorran and Steel, who observed encapsulation of hexafluorophosphate in a [L 4 Pd 2 ] 4+ complex in 1998. All reported structures have a common ground besides their structural variety, which is their positively charged nature.…”

Maximized axial helicity in a Pd2L4cage: inverse guest size-dependent compression and mesocate isomerism

“…This may relate to their acute azimuthal angles ( α < 90°), where only subtle structural distortions are required to invert helicity. 74 This means that nearly all so far postulated M 2 L 4 mesocates are transient species, rather than isolable ones. 75,76…”