Improved alkali metal ion capturing utilizing crown ether-based diblock copolymers in a sandwich-type complexation

Oral, Iklima; Abetz, Volker

doi:10.1039/d1sm01815a

Cited by 12 publications

(10 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Mit B9C3 funktionalisierte Blockcopolymere ko ¨nnen auf diese Weise selektiv Lithium aus einer wa ¨ssrigen Phase u ¨ber die Grenzfla ¨che in eine organische Phase u ¨berfu ¨hrt werden, da der la ¨ngere hydrophobe Block den hydrophilen Block abschirmt, d.h. der hydrophile Block bildet vermutlich den Kern einer Mizelle (Abb. 7) [43,90,91].…”

Section: Stabilisierung Der Membranenunclassified

Filtrationsmembranen und spezifische Adsorber auf der Basis von maßgeschneiderten selbst‐organiserenden Blockcopolymeren

Abetz

2023

Chemie Ingenieur Technik

Self Cite

View full text Add to dashboard Cite

Blockcopolymere bieten aufgrund ihrer Fähigkeit, selbstorganisierte Strukturen zu bilden, verschiedene Möglichkeiten für die Stofftrennung. Flach‐ und Hohlfadenmembranen mit regelmäßig angeordneten Poren gleichen Durchmessers und hoher Porenzahldichte können aus selbstorganisierenden Blockcopolymeren hergestellt werden. Die Porengrößen und Funktionalitäten dieser Membranen und damit deren Einsatzmöglichkeiten in der Stofftrennung können auf verschiedenen Wegen eingestellt werden, wobei die Einstellung dieser Parameter an fertigen Membranstrukturen besonders interessant ist. Weiterhin können maßgeschneiderte amphiphile Blockcopolymere zur spezifischen Extraktion von Stoffen aus wässrigen (hydrophilen) Lösungen in organische (hydrophobe) Lösungen eingesetzt werden.

show abstract

Section: Stabilisierung Der Membranenunclassified

Filtrationsmembranen und spezifische Adsorber auf der Basis von maßgeschneiderten selbst‐organiserenden Blockcopolymeren

Abetz

2023

Chemie Ingenieur Technik

Self Cite

View full text Add to dashboard Cite

show abstract

“…It implies that molecular chemical reactions, established in organic chemistry, can be employed to provide functionality while mechanical frameworks of the 2D materials are maintained. Crown ethers are macrocyclic host molecules that selectively bind alkali metal cations due to their electron-rich cavities. , The introduction of supramolecular “host–guest” chemistry of crown ethers has led to various applications in cation recognition, , biological systems, and catalysis. , For example, 18-crown-6 structure is an excellent activated agent for KI in CO 2 fixation with epoxides. , However, they have limited binding strength and selectivity due to the flexibility of the macrocyclic polyether rings. , Early studies have established that rigidifying the crown ether structure through chemical modification enhances the binding affinity. For example, Guo et al found that the crown ether incorporated in graphene generates larger binding energy (∼1.4 eV) than those obtained with free crown ether molecules …”

Section: Introductionmentioning

confidence: 99%

“…Crown ethers are macrocyclic host molecules that selectively bind alkali metal cations due to their electronrich cavities. 33,34 The introduction of supramolecular "host− guest" chemistry of crown ethers has led to various applications in cation recognition, 35,36 biological systems, 37 sis. 38,39 For example, 18-crown-6 structure is an excellent activated agent for KI in CO 2 fixation with epoxides.…”

Section: Introductionmentioning

confidence: 99%

Covalent-Frameworked 2D Crown Ether with Chemical Multifunctionality

Kim,

Park

et al. 2024

J. Am. Chem. Soc.

View full text Add to dashboard Cite

Here, we present the synthesis and characterization of a novel 2D crystalline framework, named C 2 O, which mainly consists of carbon and oxygen in a 2:1 molar ratio and features crown ether holes in its skeletal structure. The covalentframeworked 2D crown ether can be synthesized on a gram-scale and exhibits fine chemical stability in various environments, including acid, base, and different organic solvents. The C 2 O efficiently activates KI through the strong coordination of K + with crown ether holes in a rigid framework, which enhances the nucleophilicity of I − and significantly improves its catalytic activity for CO 2 fixation with epoxides. The presence of C 2 O with KI results in remarkable increases in CO 2 conversion from 5.7% to 99.9% and from 2.9% to 74.2% for epichlorohydrin and allyl glycidyl ether, respectively. Moreover, C 2 O possesses both electrophilic and nucleophilic sites at the edge of its framework, allowing for the customization of physicochemical properties by a diverse range of chemical modifications. Specifically, incorporating allyl glycidyl ether (AGE) as an electrophile or ethoxyethylamine (EEA) as a nucleophile into C 2 O enables the synthesis of C 2 O-AGE or C 2 O-EEA, respectively. These modified frameworks exhibit improved conversions of 97.2% and 99.9% for CO 2 fixation with allyl glycidyl ether, outperforming unmodified C 2 O showing a conversion of 74.2%. This newly developed scalable, durable, and customizable covalent framework holds tremendous potential for the design and preparation of outstanding materials with versatile functionalities, rendering them highly attractive for a wide range of applications.

show abstract

“…Previous research with crown ethers led to an appreciation that the stability of Na + in appropriately designed sandwich complexes is greater than in the corresponding monomeric complex due to the approximately twofold increase in ion–dipole interactions. , We thus envisioned that the conjugation of a calix[4]pyrrole core with two benzo-12-crown-4 subunits, which are known to form sandwich complexes with the Na + ion, − would allow us to create an ion pair receptor capable of recognizing and extracting NaOH. The calix[4]pyrrole-based ion pair receptors cis / trans - 1 and cis / trans - 2 (Figure ) were designed to test this hypothesis.…”

Section: Introductionmentioning

confidence: 99%

Direct Extraction of Sodium Hydroxide by Calix[4]pyrrole-Based Ion-Pair Receptors

et al. 2023

View full text Add to dashboard Cite

Described in this work are calix [4]pyrrole-based ionpair receptors, cis/trans-1 and cis/trans-2, designed for the extraction of sodium hydroxide. An X-ray diffraction analysis of a single crystal of the cis-1•NaOH isomer isolated from a mixture of cis/trans-1 revealed a unique dimeric supramolecular structure. An average dimer in toluene-d 8 solution was inferred on the basis of diffusion-ordered spectroscopy (DOSY). Support for the proposed stoichiometry came from density functional theory (DFT) calculations. The structural stability of the dimeric cis-1•NaOH complex in toluene solution was further confirmed by ab initio molecular dynamics (AIMD) simulation with explicit representation of solvent. Under conditions of liquid−liquid extraction (LLE), purified receptors cis-and trans-2 were both found to remove NaOH from a pH 11.01 aqueous source phase into toluene with extraction efficiencies (E%) of 50−60% when used equimolar to NaOH. However, in all cases, precipitation was observed. Complexities associated with precipitation could be avoided by immobilization of the receptors onto a chemically inert poly(styrene) resin by means of solvent impregnation. The use of solvent-impregnated resins (SIRs) eliminated precipitation in solution while retaining the extraction efficiency toward NaOH. This allowed both the pH and salinity of the alkaline source phase to be lowered.

show abstract

Improved alkali metal ion capturing utilizing crown ether-based diblock copolymers in a sandwich-type complexation

Abstract: The compexation behavior of metals with free crown ethers (CE) and diblock copolymer-based CE is investigated. The latter shows at least 10000 times stronger complexation than free CEs. On this...

Cited by 12 publications

References 36 publications

Filtrationsmembranen und spezifische Adsorber auf der Basis von maßgeschneiderten selbst‐organiserenden Blockcopolymeren

Filtrationsmembranen und spezifische Adsorber auf der Basis von maßgeschneiderten selbst‐organiserenden Blockcopolymeren

Covalent-Frameworked 2D Crown Ether with Chemical Multifunctionality

Direct Extraction of Sodium Hydroxide by Calix[4]pyrrole-Based Ion-Pair Receptors

Contact Info

Product

Resources

About