Supramolecular umpolung: Converting electron-rich resorcin[4]arenes into potent CH-bonding anion receptors and transporters

Chem, Год журнала: 2024, Номер 10(6), С. 1910 - 1924

Опубликована: Март 27, 2024

CH hydrogen bonding receptors constitute an emerging class of anion sensors and transporters, which, owing to their high proteolytic pH resistance, are promising for biological applications. groups, however, considered as weak bond donors, requiring activation by strongly electron-withdrawing substituents. Accordingly, electron-rich aromatic rings have never been used this purpose thus far. In work, we demonstrate that resorcin[4]arenes, well known π-electron-rich cation receptors, can be converted into CH-bonding simple substitution with four nitro groups. Owing unique geometric features, tetranitroresorcin[4]arenes acquire large dipole moments (up 15.8 D) highly positive electrostatic potentials at the lower rim, leading remarkable affinities (Ka(Cl−) = 1.36 × 105 M−1 in THF). Moreover, show also seemingly innocent alkyl chains surrounding binding site enable transport activities (EC50 down 0.012 mol%) resistance competitive aqueous/organic media.

Язык: Английский

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Facile Synthesis of Donor–Acceptor Heterocycloarenes Based on Pyrazine Derivatives Possessing Intriguing Iodide Ion Capture Properties

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(31), С. 21922 - 21931

Опубликована: Июль 25, 2024

Donor–acceptor (D–A) conjugated systems have been extensively investigated and play important roles in organic electronics. Incorporating D–A structures into (hetero)cycloarenes endows them tunable electronic properties, while the well-defined cavity remains. However, synthetic complexity of introducing electron-acceptor moieties limits their development applications. In this paper, first family electronically heterocycloarenes (DAHCn, n = 1–5) based on pyrazine derivatives was facilely synthesized through cyclocondensation reaction from a tetraketone-functionalized heterocycloarene precursor prepared using ketal-protection strategy. The effect expanded conjugation inserted electron-withdrawing group studied systematically by X-ray crystallographic analysis, various spectroscopic measurements, theoretical calculations. Interestingly, presence an polarizes inner C(sp2)–H significantly increases binding affinities to iodide anion. Meanwhile, anion affinity can be further modulated type attached substituents distance polarization. More importantly, dicyanopyrazine derivative DAHC3 shows highest strength ion as 2:1 sandwich complex (log β2 12.3 ΔG −69.1 kJ mol–1), which is strongest receptor hydrogen bonding interactions reported date. Our finding provides new strategy design synthesize strong receptors.

Язык: Английский

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Probing the Reversible Binding of Anionic Reactive Sulfur and Nitrogen Species in Imidazolium Receptors with Directional C–H Hydrogen Bonds

Inorganic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Апрель 9, 2025

H2S and NO are physiologically important signaling molecules with complex roles in biology intermolecular crosstalk. Although these species often referred to as neutral on paper, they primarily found anionic and/or oxidized forms aerobic solutions HS- or NO2-/NO3-, respectively. Despite the prominence of anions biology, particularly NO2-, few investigations have focused molecular recognition reversible binding species. Using a library imidazolium receptors C-H hydrogen bonding interactions, we investigate influences affinity through modulation charge, multiplicity, preorganization, while also investigating how anion volume impacts binding. These factors probed by solution-state titration experiments solid-state X-ray crystallographic data showing specific interactions involved guest Both NMR crystallography support importance abundance C-H···X- facilitating well conformational changes upon recognition.

Язык: Английский

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Computer-aided design of triazolo-cages as anion receptors

Physical Chemistry Chemical Physics, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Molecular cages with three-dimensional cavities have garnered significant interest due to their enhanced encapsulation abilities.

Язык: Английский

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Proline-based tripodal cages with guest-adaptive features for capturing hydrophilic and amphiphilic fluoride substances

Nature Communications, Год журнала: 2025, Номер 16(1)

Опубликована: Апрель 4, 2025

Proteins exhibit remarkable molecular recognition by dynamically adjusting their conformations to selectively interact with ligands at specialized binding sites. To bind hydrated ligands, proteins leverage amino acid residues similar water affinities as the substrate, minimizing energy required strip molecules from hydrophilic substrates. In synthetic receptor design, replicating this sophisticated adaptability remains a challenge, most artificial receptors are optimized desolvated substances. Here, we show that proline-based can mimic conformational dynamics of achieve selective and amphiphilic fluoride substances in aqueous environments. This finding highlights critical role flexibility strategic hydrophilicity enhancing ligand affinity water. Moreover, it establishes new framework for designing versatile tunable hydrophobicity profiles.

Язык: Английский

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Reversing Selectivity of Bambusuril Macrocycles toward Inorganic Anions by Installing Spacious Substituents on Their Portals

Chemical Science, Год журнала: 2024, Номер unknown

Опубликована: Дек. 6, 2024

The order of bulky 1-phenylethyl and small methyl substituents the macrocycle building blocks has a major impact on affinity selectivity toward inorganic anions.

Язык: Английский

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