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DOI number:10.1021/acscentsci.1c01571
Journal:ACS Central Science
Abstract:Efficient enantioselective separation using porous materials requires tailored and diverse pore environments to interact with chiral substrates; yet, current cage materials usually feature uniform pores. Herein, we report two porous assemblies, PCC-60 and PCC67, using isostructural octahedral cages with intrinsic microporous cavities of 1.5 nm. The PCC-67 adopts a densely packed mode, while the PCC-60 is a hierarchically porous assembly featuring interconnected 2.4 nm mesopores. Compared with PCC-67, the PCC-60 demonstrates excellent enantioselectivity and recyclability in separating racemic diols and amides. This solid adsorbent PCC-60 is further utilized as a chiral stationary phase for highperformance liquid chromatography (HPLC), enabling the complete separation of six valuable pharmaceutical intermediates. According to quantitative dynamic experiments, the hierarchical pores facilitate the mass transfer within the superstructure, shortening the equilibrium time for adsorbing chiral substrates. Notably, this hierarchically porous material PCC-60 indicates remarkably higher enantiomeric excess (ee) values in separating racemates than PCC-67 with uniform microporous cavities. Control experiments confirm that the presence of mesopores enables the PCC-60 to separate bulky substrates. These results uncover the traditionally underestimated role of hierarchical porosity in poroussuperstructure-based enantioseparation.
Indexed by:Journal paper
Correspondence Author:Zhu Chengfeng* et al.,
Volume:8
Issue:5
Page Number:562-570
Translation or Not:no
Date of Publication:2022-04-22
Included Journals:SCI
Links to published journals:https://pubs.acs.org/doi/10.1021/acscentsci.1c01571