Efficient Separation of cis‐ and trans‐1,2‐Dichloroethene Isomers by Adaptive Biphen[3]arene Crystals

• Published in: Angewandte Chemie International Edition Vol. 58; no. 30; pp. 10281 - 10284
• Main Authors: Wang, Yiliang, Xu, Kaidi, Li, Bin, Cui, Lei, Li, Jian, Jia, Xueshun, Zhao, Hongbin, Fang, Jianhui, Li, Chunju
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 22.07.2019
• Subjects: adsorption; biphenarenes; Chemistry; Chemistry, Multidisciplinary; isomers; nonporous adaptive crystals; olefins; Physical Sciences; Science & Technology; nonporous adaptive crystals; adsorption; DESIGN; isomers; SIZE; MOFS; biphenarenes; olefins; METAL-ORGANIC FRAMEWORKS; MOLECULAR RECOGNITION; DIFFRACTION; HOST-GUEST COMPLEXATION; HYDROCARBON SEPARATIONS; ALKANES
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201905563

Reported here is the highly efficient separation of industrially important cis‐ and trans‐1,2‐dichloroethene (cis‐DCE and trans‐DCE) isomers by activated crystalline 2,2′,4,4′‐tetramethoxyl biphen[3]arene (MeBP3) materials, MeBP3α. MeBP3 can be synthesized in excellent yield (99 %), and a cyclic pentamer is also obtained when using 1,2‐dichloroethane as the solvent. The structure of MeBP3 in the CH3CN@MeBP3 crystal displays a triangle‐shape topology, forming 1D channels through window‐to‐window packing. Desolvated crystalline MeBP3 materials, MeBP3α, preferentially adsorb cis‐DCE vapors over its trans isomer. MeBP3α is able to separate cis‐DCE from a 50:50 (v/v) cis/trans‐isomer mixture, yielding cis‐DCE with a purity of 96.4 % in a single adsorption cycle. Single‐crystal structures and powder X‐ray diffraction patterns indicate that the uptake of cis‐DCE triggers a solid‐state structural transformation of MeBP3, suggesting the adaptivity of MeBP3α materials during the sorption process. Moreover, the separation can be performed over multiple cycles without loss of separation selectivity and capacity. Keep it separated: The separation of cis‐ and trans‐1,2‐dichloroethene (DCE) isomers by activated crystalline biphen[3]arene materials, MeBP3α, is demonstrated. MeBP3α highly selectively adsorbs cis‐DCE from a 50:50 (v/v) cis/trans‐isomer mixture, yielding cis‐DCE with a purity of 96.4 % in a single adsorption cycle. The uptake of cis‐DCE triggers a solid‐state structural transformation of the activated MeBP3α crystals.