Chiral and robust Zr(iv)-based metal–organic frameworks built from spiro skeletons

Abstract

Chiral metal–organic frameworks (CMOFs) have emerged as an important subclass of chiral materials; however, their development is hindered substantially by limited enantiopure functional linkers and poor chemical stabilities. Here we report the design and synthesis of a total of five enantiopure spiro-based tetracarboxylate linkers with diverse functionalities and their use in connecting Zr₆ clusters to form an array of highly robust and porous CMOFs. X-ray crystallographic analysis and structure examination unambiguously revealed that the resulting CMOFs possess multifarious three-dimensional networks with novel topologies and pore systems, highlighting the great potential of chiral spiro skeletons in the fabrication of intriguing structures. PXRD and N₂ adsorption experiments validated their exceptional chemical stability towards boiling water as well as aqueous acid and base solutions. Moreover, their potential applications in enantioselective catalysis and separation are also presented.