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

Abstract

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,M eBP3a. MeBP3 can be synthesized in excellent yield (99 %), and ac yclic pentamer is also obtained when using 1,2-dichloroethane as the solvent. The structure of MeBP3 in the CH 3 CN@MeBP3 crystal displays at riangle-shape topology, forming 1D channels through window-to-windowp acking. Desolvated crystalline MeBP3 materials,M eBP3a,p referentially adsorb cis-DCE vapors over its trans isomer.MeBP3a is able to separate cis-DCE from a5 0:50 (v/v) cis/trans-isomer mixture,y ielding cis-DCE with ap urity of 96.4 %i nas ingle adsorption cycle.S ingle-crystal structures and powder X-ray diffraction patterns indicate that the uptake of cis-DCE triggers as olid-state structural transformation of MeBP3, suggesting the adaptivity of MeBP3a materials during the sorption process.M oreover,t he separation can be performed over multiple cycles without loss of separation selectivity and capacity.

Tiara[5]arenes: Synthesis, Solid‐State Conformational Studies, Host–Guest Properties, and Application as Nonporous Adaptive Crystals

“…More recently, pillararene‐based crystalline organic materials have also been shown to be effective for the separation of linear/branched alkanes, xylene isomers, styrene/ethylbenzene, toluene/methyl‐cyclohexane, and dihalobenzene isomers. Analogously, the triangular biphen[3]arene macrocycle was used to discriminate cis ‐ over trans ‐dichloroethene during preferential solid‐vapor uptake, and dual‐selective fractionations of chlorobenzene/chlorocyclohexane by two polymorphs of geminiarene featuring different conformations were also reported . These findings all intrigued us to investigate the solid‐state host–guest chemistry of tiara[5]arene‐based crystalline materials.…”

Capture of Sulfur Mustard by Pillar[5]arene: From Host-Guest Complexation to Efficient Adsorption Using Nonporous Adaptive Crystals

“…This novel class of materials was termed as nonporous adaptive crystals (NACs) ( Jie et al., 2018a , 2018b ). Very recently, NACs of other macrocycles such as biphen[ n ]arene ( Wang et al., 2019 ), hybrid[3]arene ( Zhou et al., 2020 ), leaning towerarene ( Wu et al., 2020 ), geminiarene ( Wu and Yang, 2019 ), and tiararenes ( Yang et al., 2020 ) have also been reported, showing interesting adsorption and separation properties. Notice that, in our vapor adsorption tests, SM simulants were utilized because no effective protection was available during the experiments for testing the real SM.…”

Multiple Stimuli-Responsive Conformational Exchanges of Biphen[3]arene Macrocycle

“…Here, we report the stimuli-responsive conformational exchanges of 2,2',4,4'-tetramethoxyl biphen [3]arene (MeBP3) [40][41][42][43][44][45][46]. The conformational exchanges between two conformers of MeBP3 were slow on the NMR timescale, and we successfully differentiated them in the 1 H NMR and 13 C NMR spectra of MeBP3.…”