Solvent Effects in Supramolecular Chemistry: Linear Free Energy Relationships for Common Intermolecular Interactions

The Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 87(3), P. 1602 - 1615

Published: May 11, 2021

The proper choice of solvent is major importance for all studies in supramolecular chemistry, including molecular recognition host-guest systems, intramolecular folding, self-assembly, and polymerization. In this Perspective, the usefulness linear free energy relationships (LFERs) highlighted to unravel effect solvents on coordinate bonding (e.g., cation-crown ether), hydrogen bonding, halogen dipolar aggregation, π-π-stacking. For these intermolecular interactions widely applied LFER between Gibbs binding energies common polarity scales ET(30), π*, α or β based solvatochromic dyes, derived from processes such as Gutmann donor acceptor numbers bond scales, physical functions like Kirkwood-Onsager Liptay-Onsager could be demonstrated. These can now toward a better understanding prevailing forces interactions. They further enable rational selection most suitable preparation self-assembled materials estimation constants without need time-consuming comprehensive investigations solvents.

Language: Английский

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Molecular Engineering of Noncovalent Dimerization

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(33), P. 14962 - 14975

Published: Aug. 15, 2022

Dimers are probably the simplest model to facilitate understanding of fundamental physical and chemical processes that take place in much-expanded systems like aggregates, crystals, other solid states. The molecular interplay within a dimer differentiates it from corresponding monomeric state determines its features. Molecular engineering noncovalent dimerization through applied supramolecular restrictions enables additional control over interplay, particularly dynamic aspect. This Perspective introduces recent effort has been made dimerization, including dimers, folda-dimers, macrocyclic dimers. It showcases how variation endows molecular-based materials with improved performance and/or functions enhanced emission, room-temperature phosphorescence, effective catalysis. We discuss pseudostatic dimers can sustain for long period time, yet still flexible enough adapt variations. feature allows active species decay along an alternate pathway, thereby spinning off emerging features not readily accessible conventional systems.

Language: Английский

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Intramolecular Energy and Solvent‐Dependent Chirality Transfer within a BINOL‐Perylene Hetero‐Cyclophane

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(31)

Published: May 31, 2022

Multichromophoric macrocycles and cyclophanes are important supramolecular architectures for the elucidation of interchromophoric interactions originating from precise spatial organization. Herein, by combining an axially chiral binaphthol bisimide (BBI) a bay-substituted conformationally labile twisted perylene (PBI) within cyclophane well-defined geometry, we report PBI hetero-cyclophane (BBI-PBI) that shows intramolecular energy solvent-regulated chirality transfer BBI to subunit. Excellent spectral overlap arrangement lead efficient excitation subsequent emission with high quantum yield (80-98 %) in various solvents. In contrast, is strongly dependent on respective solvent as revealed circular dichroism (CD) spectroscopy. The combination affords bright red circularly polarized luminescence (CPL) chromophore BBI.

Language: Английский

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Ultrafast Symmetry-Breaking Charge Separation in a Perylene Bisimide Dimer Enabled by Vibronic Coupling and Breakdown of Adiabaticity

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(34), P. 15539 - 15548

Published: Aug. 11, 2022

Perylene bisimides (PBIs) have received great attention in their applicability to optoelectronics. Especially, symmetry-breaking charge separation (SB-CS) PBIs has been investigated mimic the efficient light capturing and generation natural light-harvesting systems. However, unlike ultrafast CS dynamics donor-acceptor heterojunction materials, SB-CS a stacked homodimer still challenging due excimer formation absence of rigidifying surroundings such as special pair Herein, we present detailed mechanism photoinduced occurring 1,7-bis(N-pyrrolidinyl) PBI dimer within cyclophane. Through narrow-band broad-band transient absorption spectroscopy, demonstrate that is enabled by combination (1) vibrationally coherent charge-transfer resonance-enhanced (2) breakdown adiabaticity (formation diabats) state via structural solvent fluctuation. Quantum chemical calculations also underpin participation strong electron-donating substituents overall vibrational modes plays crucial role triggering SB-CS. Therefore, our work provides an alternative route facilitate thereby establishes novel strategy for design optoelectronic materials.

Language: Английский

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Orderly Self‐Assembly of Organic Fluorophores for Sensing and Imaging

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(37)

Published: May 23, 2023

Fluorescence imaging utilizing traditional organic fluorophores is extensively applied in both cellular and vivo studies. However, it faces significant obstacles, such as low signal-to-background ratio (SBR) spurious positive/negative signals, primarily due to the facile diffusion of these fluorophores. To cope with this challenge, orderly self-assembled functionalized have gained attention past decades. These can create nanoaggregates via a well-ordered self-assembly process, thus prolonging their residency time within cells settings. The development self-assembled-based an emerging field, such, review, we present summary progress challenges fluorophores, focusing on history, mechanisms, biomedical applications. We hope that insights provided herein will assist scientists further developing for situ imaging, sensing, therapy.

Language: Английский

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Organophotocatalytic Mechanisms: Simplicity or Naïvety? Diverting Reactive Pathways by Modifications of Catalyst Structure, Redox States and Substrate Preassemblies

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(11)

Published: Feb. 21, 2023

Abstract Photocatalysis is a powerful tool to assemble diverse chemical scaffolds, yet bottleneck on its further development the understanding of multitude possible pathways when practitioners rely only oversimplified thermodynamic and optical factors. Recently, there growing number studies in field that exploit, inter alia , kinetic parameters organophotocatalysts are synthetically more programmable terms their redox states opportunities for aggregation with target substrate. Non‐covalent interactions play key role enables access new generation reactivities such as those open‐shell organophotocatalysts. In this review, we discuss how targeted structural modifications influence organophotocatalytic mechanisms together underlying principles. We also highlight benefits strategies preassembly static quenching overcome common reactivity issues (e. g., diffusion rate limits energetic limits).

Language: Английский

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Solutes in solvent resistant and solvent tolerant nanofiltration: How molecular interactions impact membrane rejection

Journal of Membrane Science, Journal Year: 2023, Volume and Issue: 677, P. 121595 - 121595

Published: March 21, 2023

Language: Английский

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Precise Modulation of Intramolecular Aggregation‐induced Electrochemiluminescence by Tetraphenylethylene‐based Supramolecular Architectures

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(46)

Published: Sept. 25, 2023

Abstract The precisely modulated synthesis of programmable light‐emitting materials remains a challenge. To address this challenge, we construct four tetraphenylethylene‐based supramolecular architectures (SA, SB, SC, and SD), revealing that they exhibit higher electrochemiluminescence (ECL) intensities efficiencies than the tetraphenylethylene monomer can be classified as highly efficient intramolecular aggregation–induced (PI‐AIECL) systems. best‐performing system (SD) shows high ECL cathodic efficiency exceeding benchmark tris(2,2′‐bipyridyl)ruthenium(II) chloride in aqueous solution by nearly six‐fold. electrochemical characterization these an organic solvent provides deeper mechanistic insights, SD features lowest band gap. Density functional theory calculations indicate gap guest ligand structure is smallest most closely matched to host scaffold. Finally, used realize ECL‐based cysteine detection (detection limit=14.4 nM) real samples. Thus, study not only strategy allowing chromophores controllably regulated on molecular scale, but also inspires high‐performance aggregation‐induced emitters.

Language: Английский

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Engineering Soluble Diketopyrrolopyrrole Chromophore Stacks from a Series of Pd(II)‐Based Ravels**

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(40)

Published: July 17, 2023

Abstract A strategy to engineer the stacking of diketopyrrolopyrrole (DPP) dyes based on non‐statistical metallosupramolecular self‐assembly is introduced. For this, DPP backbone equipped with nitrogen‐based donors that allow for different discrete assemblies be formed upon addition Pd(II), distinguished by number π‐stacked chromophores. Pd 3 L 6 three‐ring, a heteroleptic 2 L′ ravel composed two crossing DPPs (flanked carbazoles), and unprecedented self‐penetrated motifs (a triple 4 quadruple stack), were obtained systematically investigated. With increasing counts stacked chromophores, UV/Vis absorptions red‐shift emission intensities decrease, except compound , which stands out an exceptional photoluminescence quantum yield 51 %. This extraordinary open‐shell metal containing explainable intra‐assembly FRET process. The modular design synthesis soluble multi‐chromophore building blocks offers potential preparation nanodevices materials applications in sensing, photo‐redox catalysis optics.

Language: Английский

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A Chirally Locked Bis-perylene Diimide Macrocycle: Consequences for Chiral Self-Assembly and Circularly Polarized Luminescence

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(8), P. 5470 - 5479

Published: Feb. 14, 2024

Macrocycles containing chiral organic dyes are highly valuable for the development of supramolecular circularly polarized luminescent (CPL) materials, where a preorganized framework is conducive to directing π–π self-assembly and delivering strong persistent CPL signal. Here, perylene diimides (PDIs) an excellent choice dye component because, alongside their tunable photophysical properties, functionalization PDI's core yields twisted, π-system, capable CPL. However, configurationally stable PDI-based macrocycles rare, those that also beyond dimers unprecedented, both which advantageous robust self-assembled chiroptical materials. In this work, we report first bay-connected bis-PDI macrocycle (ΔG⧧ > 155 kJ mol–1). We use chirally locked uncover new knowledge PDI perform quantitative imaging resulting single-crystal As such, discover chirality 1,7-disubstituted provides rational route designing H-, J- concomitant H- J-type important arrangements optimizing (chir)optical charge/energy transport properties. Indeed, reveal amplified in single crystals our by quantifying degree emitted light circular polarization from such materials time using CPL-Laser Scanning Confocal Microscopy.

Language: Английский

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