Ultradynamic Isoreticularly Expanded Porous Organic Crystals

Zhang, Yunjia; Liang, Rongran; Atterberry, Benjamin A.; Li, Fangzhou; Staples, Richard J.; Zhang, Jian; Samanta, Jayanta; Rossini, Aaron J.; Ke, Chenfeng

doi:10.1021/jacs.4c04245

DOE OSTI · 2368781

Ultradynamic Isoreticularly Expanded Porous Organic Crystals

Zhang, Yunjia·Liang, Rongran·Atterberry, Benjamin A.·Li, Fangzhou·Staples, Richard J.·Zhang, Jian·Samanta, Jayanta·Rossini, Aaron J.·Ke, Chenfeng

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Abstract

Porous organic materials showcasing large framework dynamics present new paths for adsorption and separation with enhanced capacity and selectivity beyond the size-sieving limits, which is attributed to their guest-responsive sorption behaviors. Porous hydrogen-bonded crosslinked organic frameworks (H C OFs) are attractive for their remarkable ability to undergo guest-triggered expansion and contraction facilitated by their flexible covalent crosslinkages. However, the voids of H C OFs remain limited, which restrains the extent of the framework dynamics. Here in this work, we synthesized a series of H C OFs characterized by unprecedented size expansion capabilities induced by solvents. These H C OFs were constructed by isoreticularly co-crystallizing two complementary sets of hydrogen bonding building blocks to generate porous molecular crystals, which were crosslinked through thiol–ene/yne single-crystal-to-single-crystal transformations. The generated H C OFs exhibit enhanced chemical durability, high crystallinity, and extraordinary framework dynamics. For instance, H C OF-104 crystals featuring a pore diameter of 13.6 Å expanded in DMF to 300 ± 10% of their original lengths within just 1 min. This expansion allows the HCOFs to adsorb guest molecules that are significantly larger than the pore sizes of their crystalline states. Through methanol-induced contraction, these large guests were encapsulated in the fast-contracted H C OFs. These advancements in porous framework dynamics pave the way for new methods of encapsulating guests for targeted delivery.

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Zhang, Yunjia, Liang, Rongran, Atterberry, Benjamin A., Li, Fangzhou, Staples, Richard J., Zhang, Jian, Samanta, Jayanta, Rossini, Aaron J., Ke, Chenfeng. 2024-05-23. Ultradynamic Isoreticularly Expanded Porous Organic Crystals. https://doi.org/10.1021/jacs.4c04245

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