A rigid phenyl-based covalently interlocked macrocycle with inherent porosity

Abstract

The precise construction of three-dimensional (3D) carbon networks consisting solely of sp² hybridized atoms has long been pursued in carbon nanoscience. Herein, we report the bottom-up synthesis of a covalently interlocked macrocycle ([2]CIM) featuring a molecular core of 31 benzene units. X-ray crystallography unambiguously confirmed the covalently interlocked structure of [2]CIM, revealing a rigid 3D architecture with inherent porosity. Its conformational rigidity and solid-state packing enable it to be a promising molecular porous material, exhibiting a specific surface area (SA_BET) of 507 m² g⁻¹. Gas absorption studies demonstrated the preferential adsorption of ethane (C₂H₆) over ethene (C₂H₄) by the phenyl-based covalently interlocked macrocycle. [2]CIM exhibits a unique gas separation performance among discrete phenyl-based porous macrocycles.