# Stereospecific Assembly of Triply Chiral Pseudopeptidic Cages Through Dynamic Dual Chirality Transfer

## TL;DR

Scientists created chiral cages using dynamic chemical processes, showing how chirality can be transferred and controlled in complex molecular structures.

## Contribution

The study introduces a dynamic dual chirality transfer mechanism for assembling triply chiral pseudopeptidic cages with high stereocontrol.

## Key findings

- Chiral information is transferred through reversible imine bonds and metal coordination in octahedral Fe(II) complexes.
- A configurationally stable Ru(II) complex enables stereospecific selection of chiral elements with high fidelity.
- The system generates water-soluble homochiral macrobicyclic pseudopeptides with unique chemical and photophysical properties.

## Abstract

A stereospecific transmission of chiral information within tripodal pseudopeptidic cages has been observed from dynamic constitutional co‐operation of reversible orthogonal processes: imine bond and metal coordination. The chiral centers from the phenylalanine amino acid moieties induce a specific chirality into the formed octahedral Fe(II) complex and into the helical twist of the macrobicycle, as confirmed by NMR, circular dichroism, X‐ray diffraction of single crystals, and theoretical calculations. Instead, when a configurationally stable Ru(II) complex is employed, the dynamic imine exchange efficiently selects the corresponding matched‐combination of the same chiral elements, leading after reduction to a water‐soluble homochiral stable macrobicyclic pseudopeptide Ru(II) complex with appealing chemical and photophysical properties. Overall, our study demonstrates how subtle structural factors from a chiral effector in a reversible dynamic system rule the generation and selection of subsequent chiral elements with high fidelity and complete stereocontrol.

The spontaneous assembly of triply chiral (L, Δ, P or D, Λ, M) cages has been achieved from a simple tripodal chiral effector based on phenylalanine tris(amidoamine), non‐chiral bipyridine dialdehyde, and a metal ion. Orthogonal imine bond and iron (II) coordination generate a single combination of chiral elements, while configurationally stable ruthenium (II) allows their stereospecific selection, reflecting a highly efficient dynamic chiral information transfer.