Chiral proline-substituted porous organic cages in asymmetric organocatalysis

The efficient preparation of chiral porous organic cages (POCs) with specific functions is challenging, and their application in asymmetric catalysis has not previously been explored. In this work, we have achieved the construction of chiral POCs based on a supramolecular tetraformyl-resorcin[4]aren...

Full description

Saved in:
Bibliographic Details
Published in:Chemical science (Cambridge) 2022-03, Vol.13 (12), p.3582-3588
Main Authors: Xu, Ning, Su, Kongzhao, El-Sayed, El-Sayed M, Ju, Zhanfeng, Yuan, Daqiang
Format: Article
Language:English
Subjects:
Aldehydes
Biomimetics
Cages
Catalysis
Chemistry
Diamines
Proline
Spatial distribution
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The efficient preparation of chiral porous organic cages (POCs) with specific functions is challenging, and their application in asymmetric catalysis has not previously been explored. In this work, we have achieved the construction of chiral POCs based on a supramolecular tetraformyl-resorcin[4]arene scaffold with different chiral proline-modified diamine ligands and utilizing dynamic imine chemistry. The incorporation of V-shaped or linear chiral diamines affords the [4 + 8] square prism and [6 + 12] octahedral POCs respectively. The appended chiral proline moieties in such POCs make them highly active supramolecular nanoreactors for asymmetric aldol reactions, delivering up to 92% ee. The spatial distribution of chiral catalytic sites in these two types of POCs greatly affects their catalytic activities and enantioselectivities. This work not only lays a foundation for the asymmetric catalytic application of chiral POCs, but also contributes to our understanding of the catalytic function of biomimetic supramolecular systems. Two calix[4]resorcinarene-based chiral POCs with different self-assembly forms were constructed. The difference in the spatial distribution of chiral organocatalytic sites leads to the two chiral POCs exhibiting distinct stereoselectivities.
ISSN:2041-6520
2041-6539
DOI:10.1039/d2sc00395c