Synergistic Covalent and Hydrogen-Bonding Interactions Drive the Assembly of a Gigantic Snub Cube

Spontaneous self-assembly processes that lead to gigantic discrete cage architectures via weak interactions are common in nature. However, the rational design of large, robust artificial hydrogen-bonded organic cages (HOCs) presents significant challenges. Herein, an extra-large hydrogen-bonded snub cube (HSC), one of the 13 Archimedean solids, has been designed and synthesized from 6 tetraformyl-calix[4]resorcinarene and 24 amine-functionalized pyrazole building blocks via dual covalent and hydrogen-bond linkage strategy. Single-crystal X-ray crystallography revealed that HSC was stabilized by 24 intramolecular β-ketoenamine N–H···O, 24 intramolecular calix[4]resorcinarene O–H···O, and 24 intermolecular pyrazole N–H···N hydrogen-bonding interactions. Its cavity volume reaches 5391 Å3, making it one of the largest reported HOCs. Moreover, host–guest studies revealed the selectivity of HSC for C70 over C60, highlighting its potential as supramolecular adsorbent for fullerene separation.