Supramolecular Snub Cubes

Snub cubes are chiral polyhedral structures formed by combining 32 triangular and six square faces, and in supramolecular chemistry, as reported by reserchers from China and the US, the chiral structures are dynamic, non-covalently assembled systems with unique geometries and functional properties, mimicking biological encapsulants such as viral capsids or which might be useful for chiral separations or asymmetric catalysis.

Huang Wu (Tianjin University, China, and The University of Hong Kong), Wenping Hu and Yu Wang (Tianjin University), and J. Fraser Stoddart (The University of Hong Kong, Northwestern University, Evanston, IL, USA, University of New South Wales, Sydney, Australia, Zhejiang University, Hangzhou, China, and ZJU-Hangzhou Global Scientific and Technological Innovation Centre, Hangzhou, China) have synthesized enantiomerically pure snub cubes comprising of 12 helical macrocycles, which are held together by 144 weak C–H hydrogen bonds. The cubes have external diameters of 5.1 nm, contain 2,712 atoms, and chiral cavities with volumes of 6,215 Å.

The synthesis began with the photoactivation of diarylethene-based dialdehydes using ultraviolet light, converting them into their closed enantiopure forms, (2R)- and (2S)-closed diarylethene, which were then isolated through chiral high-performance liquid chromatography. Subsequently, (4R)-diaminocyclohexane-functionalized naphthalenediimide and (2R)-closed diarylethene were refluxed together in chloroform for two days, producing a [2 + 2] macrocycle, which further self-assembled into the large supramolecular structure.

In addition to their reversible photochromic behavior, the elasticity and hardness of the snub cubes can be reversibly regulated by light. Furthermore, the snub cubes have the capacity to accommodate numerous small guest molecules simultaneously and can separately encapsulate two different guest molecules in the different compartments of their framework.

This research belive that their work represents an important advance in mimicking biological encapsulants, from chiral topological superstructures to dynamic and binding properties, and lays the foundation for the development of advanced biomimetic materials.

Dynamic supramolecular snub cubes,
Huang Wu, Yu Wang, Luka Đorđević, Pramita Kundu, Surojit Bhunia, Aspen X.-Y. Chen, Liang Feng, Dengke Shen, Wenqi Liu, Long Zhang, Bo Song, Guangcheng Wu, Bai-Tong Liu, Moon Young Yang, Yong Yang, Charlotte L. Stern, Samuel I. Stupp, William A. Goddard III, Wenping Hu, J. Fraser Stoddart,
Nature 2025, 637, 347–353.
https://doi.org/10.1038/s41586-024-08266-3