Issue 33, 2024

Helicity control of a polyaromatic coordination capsule through stereoselective CH–π interactions

Abstract

Although square-planar ML4 units are essential building blocks for coordination cages and capsules, the non-covalent control of the chirality and helicity of the resultant nanostructures is quite difficult. Here we report the helicity control of an M2L4 polyaromatic capsule, formed from metal ions with square-planar coordination geometry and bent bispyridine ligands, through stereoselective CH–π interactions with monosaccharide derivatives. Thanks to host–guest CH–π multi-interactions, one molecule of various permethylated monosaccharides is quantitatively bound by the capsule in water (Ka up to >108 M−1). In the polyaromatic cavity, among them, the selective binding of a β-glucose derivative (>80 : 20 ratio) is demonstrated from a mixture of the α/β-glucoses, through the equatorial-selective recognition of the anomeric (C1) group. A similar stereoselective binding is accomplished from an α/β-galactose mixture. Interestingly, single equatorial/axial configurations on the bound monosaccharides can regulate the helical conformation of the capsule in water, confirmed by CD, NMR, and theoretical analyses. An intense capsule-based Cotton effect is exclusively observed upon encapsulation of the permethylated α-glucose (>20-fold enhancement as compared to the β-glucose derivative), via the induction of a single-handed host helicity to a large extent. Inverse capsule helicity is induced by the binding of a β-galactose derivative under the same conditions.

Graphical abstract: Helicity control of a polyaromatic coordination capsule through stereoselective CH–π interactions

Supplementary files

Article information

Article type
Edge Article
Submitted
30 Mäe 2024
Accepted
29 Jun 2024
First published
05 Jul 2024
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY-NC license

Chem. Sci., 2024,15, 13234-13239

Helicity control of a polyaromatic coordination capsule through stereoselective CH–π interactions

N. Kishida, H. Sasafuchi, T. Sawada and M. Yoshizawa, Chem. Sci., 2024, 15, 13234 DOI: 10.1039/D4SC02103G

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements