Preprint: Squarephaneic tetraanhydride – A building block for redox-active porous organic materials

Our preprint reporting a unique new aromatic carboxylic anhydride building block for the synthesis of redox-active porous organic materials has been posted on ChemRxiv.


Some time ago, we showed that switching between local and global aromaticity in the macrocycle PCT enables high-performance organic sodium-ion battery anodes. However, until now, a suitable building block for a broader use of PCT as a (sub)structure in organic materials was missing.


In our new preprint, we present such a building block: Squarephaneic tetraanhydride. It can be synthesised in just three steps and features PCT as an integral component as well as four carboxylic anhydride groups for further functionalisation, e.g. conversion into imides.


The crystal structures of the tetraanhydride and one of the synthesised tetraimides demonstrate the high degree of porosity achievable with the new building block. We also found excellent electrochemical properties for all tetraimides. Considering the short synthesis and unique properties, we expect widespread use of the new building block in the development of redox-active porous organic materials.


S. Eder, D. B. Thornton, B. Ding, D. Sammut, A. J. P. White, F. Plasser, I. E. L. Stephens, M. Heeney, S. Mezzavilla, F. Glöcklhofer,* Squarephaneic Tetraanhydride: A Conjugated Square-Shaped Cyclophane for the Synthesis of Porous Organic Materials, ChemRxiv 2022, preprint, DOI:10.26434/chemrxiv-2022-p4p5d. [Preprint link, open access]