Selective binding of anions by rigidified nanojars: sulfate <i>vs.</i> carbonate

Isawi, Wisam A. Al; Salome, Austin Z.; Ahmed, Basil M.; Zeller, Mat­thias; Mezei, Gellert

doi:10.1039/d1ob01318a

Cited by 8 publications

(12 citation statements)

References 117 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…All commercially available chemicals were used as received. (Bu 4 N) 2 [SO 4 ⊂{Cu n (OH) n (pzCH 2 CH 2 pz) n /2 }] ( n = 26–30) was synthesized according to a published procedure . NMR spectra were collected on a Jeol JNM-ECZ400S instrument.…”

Section: Methodsmentioning

confidence: 99%

“…(Bu 4 N) 2 [SO 4 ⊂{Cu n (OH) n (pzCH 2 CH 2 pz) n/2 }] (n = 26−30) was synthesized according to a published procedure. 47 NMR spectra were collected on a Jeol JNM-ECZ400S instrument. Synthesis of N,N,N-Tribenzyl-N-methylammonium Iodide (TBMAI).…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

“…Thus, nanojars can selectively bind either carbonate or sulfate from an equimolar mixture of the two anions by using either an ethylene or a propylene tether between pairs of pyrazole moieties. 46,47 With incarcerated CO 3 2− , SO 4 2− , HPO 4 2− , and HAsO 4 2− ions, single crystals suitable for X-ray diffraction were readily obtained by vapor diffusion of hexane into toluene solutions of the (Bu 4 N) 2 [anion⊂{Cu(OH)(pz)} n ] nanojars. 41,48,49 With other anions, such as SeO 3 2− and HPO 3 2− described here, no suitable crystals could be obtained using the same solvent system.…”

Section: ■ Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Tribenzyl(methyl)ammonium: A Versatile Counterion for the Crystallization of Nanojars with Incarcerated Selenite and Phosphite Ions and Tethered Pyrazole Ligands

Isawi

Zeller

Mezei

2022

Crystal Growth & Design

Self Cite

View full text Add to dashboard Cite

One hundred and thirty-five years after its initial discovery, the crystal structure of the tribenzyl(methyl)ammonium (TBMA + ) cation is reported for the first time (as the nitrate salt). It is shown that TBMA + is an excellent counterion for the crystallization of large supramolecular assemblies. Thus, single crystals of previously uncrystallizable nanojars with incarcerated selenite and phosphite ions, as well as tethered pyrazole ligands, have been successfully grown by solvent vapor diffusion into solutions with added (TBMA)NO 3 . X-ray diffraction studies reveal a variety of possible noncovalent interactions between pairs of TBMA + cations. Indeed, the structurally adaptable TBMA + dimer can take on different shapes and sizes to maximize supramolecular interactions with neighboring molecules and to fill up voids in the crystal lattice. The new nanojar crystal structures (TBMA)(Bu 4 N)[SeO 3 ⊂{Cu(OH)(pz)} 28 ] and (TBMA) 2 [HPO 3 ⊂{Cu(OH)(pz)} 29 ] (pz = pyrazolate) provide unprecedented examples of noncovalently bound selenite and phosphite ions in supramolecular complexes. The use of TBMA + counterions has also allowed for the crystallization of a nanojar based on tethered pyrazole ligands, (TBMA) 2 [SO 4 ⊂{Cu 28 (OH) 28 (pzCH 2 CH 2 pz) 14 }]. The synthesis and mass spectrometric studies of the new nanojars are presented along with crystallographic studies detailing the nanojar structure, anion binding, and nanojar− counterion/counterion−counterion supramolecular interactions in the crystal lattice. Finally, the binding of SeO 3 2− and SO 4 2− ions by the same Cu 28 nanojar and the binding of HPO 3 2− , CO 3 2− , and SO 4 2− ions by the same Cu 29 nanojar are contrasted, and the δ/λ chelate-ring isomerism in the tethered-ligand nanojar is discussed.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: ■ Experimental Sectionmentioning

confidence: 99%

Section: ■ Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Tribenzyl(methyl)ammonium: A Versatile Counterion for the Crystallization of Nanojars with Incarcerated Selenite and Phosphite Ions and Tethered Pyrazole Ligands

Isawi

Zeller

Mezei

2022

Crystal Growth & Design

Self Cite

View full text Add to dashboard Cite

show abstract

“…9 Selective binding of oxyanions has recently been achieved by tethering pairs of pyrazolate ligands together. 10,11 Aiming at detecting NJs using fluorescence and ultimately developing NJ-based sensors for oxyanions, we pursued the synthesis and characterization of fluorescent NJs. Various polar substituents (including nitro, amine, aldehyde, carboxylate) as well as acidic groups (phenol, thiol, carboxylic acid) interfere with NJ formation.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Consequently, NJs have been developed into highly efficient anion-extracting agents, capable of binding trace amounts of oxyanions and transferring even the most hydrophilic ones from water into long-chain aliphatic hydrocarbon solvents . Selective binding of oxyanions has recently been achieved by tethering pairs of pyrazolate ligands together. , …”

Section: Introductionmentioning

confidence: 99%

Pyrene-Functionalized Fluorescent Nanojars: Synthesis, Mass Spectrometric, and Photophysical Studies

et al. 2021

Self Cite

View full text Add to dashboard Cite

Nanojars are a class of supramolecular coordination complexes based on pyrazolate, Cu2+, and OH– ions that self-assemble around highly hydrophilic anions and serve as efficient anion binding and extraction agents. In this work, the synthesis, characterization, and photophysical properties of pyrene-functionalized fluorescent nanojars are presented. Three pyrene derivatives, 4-(pyren-1-yl)pyrazole (HL1), 4-(5-(pyren-1-yl)pent-4-yn-1-yl)pyrazole (HL2), and 4-(3-(pyrazol-4-yl)propyl)-1-(pyren-1-yl)-1,2,3-triazole (HL3), and the corresponding nanojars were synthesized and characterized using nuclear magnetic resonance spectroscopy and mass spectrometry. Electronic absorption, steady-state, and time-resolved fluorescence measurements were carried out to understand the interaction between the pyrene fluorophore and copper nanojars. Optical absorption measurements have shown minor ground state interaction between the fluorophore and nanojars. The fluorescence of pyrene is significantly quenched when attached to nanojars, suggesting strong contribution from the paramagnetic Cu2+ ions. Significant static quenching is observed in the case of L1, when pyrene is directly bound to the nanojar, whereas in the case of L2 and L3, when pyrene is attached to the nanojars using flexible tethers, both static and dynamic quenching are observed.

show abstract

Selectivity Rule of Cryptands for Anions: Molecular Rigidity and Bonding Site

Wang

2023

Chemistry A European J

View full text Add to dashboard Cite

Cryptands utilize inside CH or NH groups as hydrogen bond (H‐bond) donors to capture anions such as halides. In this work, the nature and selectivity of confined hydrogen bonds inside cryptands were computationally analyzed with the energy decomposition scheme based on the block‐localized wavefunction method (BLW‐ED), aiming at an elucidation of governing factors in the binding between cryptands and anions. It was revealed that the intrinsic strengths of inward hydrogen bonds are dominated by the electrostatic attraction, while the anion preferences (selectivity) of inner CH and NH hydrogen bonds are governed by the Pauli exchange repulsion and electrostatic interaction, respectively. Typical conformers of cages are classified into two groups, including the C3(h)‐symmetrical conformers, in which all halide anions are located near the centroids of cages, and the “semi‐open” conformers, which exhibit shifted bonding sites for different halide anions. Accordingly, the difference in governing factors of selectivity is attributed to either the rigidity of cages or the binding site of anions for these two groups. In details, the C3 conformers of NH cryptands can be enlarged more remarkably than the C3(h)‐symmetrical conformers of CH cryptands as the size of anion (ionic radius) increases, resulting in the relaxation of the Pauli repulsion and a dramatic reduction in electrostatic attraction, which eventually rules the selectivity of NH cryptands for halide anions. By contrary, the CH cryptands are more rigid and cannot effectively reduce the Pauli repulsion, which subsequently governs the anion preference. Unlike C3 conformers whose rigidity determines the selectivity, semi‐open conformers exhibit different binding sites for different anions. From F− to I−, the bonding site shifts toward the outside end of the pocket inside the semi‐open NH cryptand, leading to the significant reduction of the electrostatic interaction that dominates the anion preference. Differently, binding sites are much less affected by the size of anion inside the semi‐open CH cryptand, in which the Pauli exchange repulsion remains the key factor for the selectivity of inner hydrogen bonds.

show abstract

Selective binding of anions by rigidified nanojars: sulfate vs. carbonate

Abstract: By using nanojars as anion binding agents, selectivity for either carbonate or sulfate can be achieved upon rigidification of the nanojar outer-shell with tethers of varying lengths between pairs of pyrazole ligands.

Cited by 8 publications

References 117 publications

Tribenzyl(methyl)ammonium: A Versatile Counterion for the Crystallization of Nanojars with Incarcerated Selenite and Phosphite Ions and Tethered Pyrazole Ligands

Tribenzyl(methyl)ammonium: A Versatile Counterion for the Crystallization of Nanojars with Incarcerated Selenite and Phosphite Ions and Tethered Pyrazole Ligands

Pyrene-Functionalized Fluorescent Nanojars: Synthesis, Mass Spectrometric, and Photophysical Studies

Selectivity Rule of Cryptands for Anions: Molecular Rigidity and Bonding Site

Contact Info

Product

Resources

About