Ferrocene as an iconic redox marker: From solution chemistry to molecular electronic devices

Coordination Chemistry Reviews, Год журнала: 2022, Номер 473, С. 214816 - 214816

Опубликована: Сен. 9, 2022

Язык: Английский

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Red Emissive Double Aza[7]helicenes with Antiaromaticity / Aromaticity Switching via the Redox‐Induced Radical Cation and Dication Species

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(18)

Опубликована: Март 6, 2023

We herein present the synthetic approach to a new antiaromatic double aza[7]helicene C that features NN-embedded polycyclic aromatic hydrocarbons (PAHs). This heteroatom-doped helicene showed rarely obtained long-wavelength emission and far-red circularly polarized luminescence (CPL) in solid state. These optical chiroptical properties could be ascribed both NN-PAH core structure further extension through angular ring fusions. Such unique electronic also culminated facile chemical oxidations of neutral positively charged chiral radical (C⋅+ ) dication species (C2+ ). Interestingly, DFT computations revealed pyridazine central an antiaromaticity-to-aromaticity switching, contrast inversed transition for helical periphery cationic states. The reported approaches are anticipated lead development redox-active systems potential applications chiroptoelectronics, spintronics as well fluorescent bioimaging.

Язык: Английский

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Chiroptical Amplification of Induced Circularly Polarized Luminescence in Nucleotide‐Templated Supramolecular Polymer

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(38)

Опубликована: Авг. 3, 2023

Efficient circularly polarized luminescence (CPL) from purely organic molecules holds great promise for applications in displays, sensing, and bioimaging. However, achieving high dissymmetry values (glum ) chromophores remains a significant challenge. Herein, we present bioinspired approach using adenosine triphosphate (ATP)-triggered supramolecular polymerization of naphthalene diimide-derived monomer (ANSG) to induce CPL with remarkable glum value 1.1×10-2 . The ANSG undergo templated, chiral self-assembly through cooperative growth mechanism the presence ATP, resulting scrolled nanotubes aggregation-induced enhanced emission (AIEE) induced CPL. Furthermore, demonstrate concept chiroptical amplification by efficiently amplifying asymmetry mixture ATP achiral pyrophosphate. This innovative opens numerous opportunities emerging field luminescence.

Язык: Английский

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π-Extended Helical Multilayer Nanographenes with Layer-Dependent Chiroptical Properties

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(49), С. 26824 - 26832

Опубликована: Дек. 4, 2023

Helical nanographenes (NGs) have attracted increasing attention recently because of their intrinsic chirality and exotic chiroptical properties. However, the efficient synthesis extended helical NGs featuring a multilayer topology is still underdeveloped, layer-dependent properties remain elusive. In this study, we demonstrate modular synthetic strategy to construct series novel (1-3) with through consecutive Diels-Alder reaction regioselective cyclodehydrogenation from readily accessible phenanthrene-based precursors bearing ethynyl groups. The resultant exhibit bilayer, trilayer, tetralayer structures elongated π extension rigid backbones, as unambiguously confirmed by single-crystal X-ray or electron diffraction analysis. We find that photophysical these are notably influenced degree extension, which varies number layers, leading obvious redshifted absorption, fast rising molar extinction coefficient (ε), markedly boosted fluorescence quantum yield (Φf). Moreover, embedded [7]helicene subunits in result stable chirality, enabling both chiral resolution exploration Profiting good alignment electric magnetic dipole moments determined structure, excellent circular dichroism circularly polarized luminescence response unprecedented high CPL brightness up 168 M-1 cm-1, rendering them promising candidates for emitters.

Язык: Английский

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Synthesis of Aza[n]helicenes up to n = 19: Hydrogen-Bond-Assisted Solubility and Benzannulation Strategy

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(25), С. 17428 - 17437

Опубликована: Июнь 12, 2024

Synthetic challenges toward anomalous structures and electronic states often involve handling problems such as insolubility in common organic solvents oxidative degradation under aerobic conditions. We designed benzo-annulated aza[n]helicenes, which benefit from both the suppressed elevation of highest occupied molecular orbital (HOMO) energies high solubility due to hydrogen bonding with solvent molecules overcome these challenges. This strategy enabled synthesis six new aza[n]helicenes ([n]AHs) different lengths (n = 9–19) acyclic precursors via one-pot intramolecular fusion reactions. The all synthesized were determined by X-ray diffraction (XRD) analysis, their electrochemical potentials measured cyclic voltammetry. Among [17]AH [19]AH are first heterohelicenes a triple-layered helix. noncovalent interaction (NCI) plots confirm existence an effective π–π between layers. absorption fluorescence spectra red-shifted helical increased, without any distinct saturation points. optical resolutions N-butylated [9]AH, [11]AH, [13]AH, [15]AH accomplished, circular dichroism (CD) circularly polarized luminescence (CPL) measured. Thus, structural, (chir)optical, properties comprehensively analyzed.

Язык: Английский

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Enhancing Chiroptical Responses in Helical Nanographenes via Geometric Engineering of Double [7]Helicenes

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(19)

Опубликована: Фев. 19, 2024

Helical nanographenes with high quantum yields and strong chiroptical responses are pivotal for developing circularly polarized luminescence (CPL) materials. Here, we present the successful synthesis of novel π-extended double [7]helicenes (ED7Hs) where two helicene units fused at meta- or para-position middle benzene ring, respectively, as structural isomers reported ortho-fused ED7H. The geometry these ED7Hs is clearly characterized by single-crystal X-ray analysis. Notably, this class exhibits bright exceeding 40 %. Through geometric regulation embedded [7]helicene from ortho-, to para-position, display exceptional amplification in responses. This enhancement evident a remarkable approximate fivefold increase absorbance dissymmetry factors (g

Язык: Английский

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A chemical perspective on the chiral induced spin selectivity effect

National Science Review, Год журнала: 2024, Номер 11(9)

Опубликована: Июнь 20, 2024

This review discusses opportunities in chemistry that are enabled by the chiral induced spin selectivity (CISS) effect. First, begins with a brief overview of seminal studies on CISS. Next, we discuss different material systems whose properties can be tailored through chemical means, special emphasis hybrid organic-inorganic layered materials exhibit some largest filtering to date. Then, promise CISS for reactions and enantioseparation before concluding.

Язык: Английский

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Helical Ladder Oligomers Exhibit Amplified Circularly Polarized Emission

Advanced Optical Materials, Год журнала: 2025, Номер unknown

Опубликована: Янв. 30, 2025

Abstract Establishing design principles to engineer molecules that exhibit strong circularly polarized luminescence (CPL)‐brightness across the UV, visible and NIR spectral range remains an unsolved challenge. To achieve a large CPL‐brightness, main difficulty is optimize dissymmetry factor g lum . Herein described discovery multi‐helicene system based on series of annulated [6]helicenes perylenediimides, exhibits larger‐than‐linear amplification with helicene length. Large enhanced fluorescent quantum yields extinction coefficients are also observed for this length series. Consequently, oligomers exceptional CPL brightness (B ) above 1 × 10 3 mol −1 cm Using computational methods density functional theory (DFT), experimental trend shows increase glum due progressive alignment magnetic (|m|) electric transition (|µ|) dipole moment vectors, as helical backbone grows longer.

Язык: Английский

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Transmitting biomolecular chirality into carbon nanodots: a facile approach to acquire chiral light emission at the nanoscale

Chemical Science, Год журнала: 2022, Номер 14(3), С. 491 - 498

Опубликована: Ноя. 28, 2022

Since the observation of chirality at nanoscale, research focused towards design and synthesis optically active nanomaterials has been a brisk pace. In this regard, carbon based zero dimensional have attracted vast attention due to their rich optical properties, abundance raw materials, minimal environmental hazardousness, good solubility, ease surface modification. However, efforts chiral nanodots exhibiting activity both in ground excited states are rather scarce. Herein, we report facile synthetic approach for preparation three sets intrinsically that exhibit intense circularly polarized luminescence. Synthesis under optimized conditions using l- d-isomers precursors led formation displayed mirror image circular dichroism luminescence signals revealing state chirality. The experimental results supportive reported core-shell model comprising an achiral core is enclosed within amorphous shell contributing anisotropy wavelength could be tuned by varying such as temperature pH. emissive properties nanoparticles demonstrated free-standing polymeric films potential used light emitting agents devices, data storage security tags. Being first intrinsic from range nanodots, solution solid state, envisage work will open new avenues investigation stated nanoscale.

Язык: Английский

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Inverted and Amplified CP‐EL Behavior Promoted by AIE‐Active Chiral Co‐Assembled Helical Nanofibers

Advanced Materials, Год журнала: 2022, Номер 35(8)

Опубликована: Дек. 8, 2022

It is well-known that high-performance circularly polarized organic light-emitting diodes (CP-OLEDs) remain a formidable challenge to the future application of luminescent (CPL)-active materials. Herein, design pair AIE-active chiral enantiomers (L/D-HP) described construct co-assemblies with an achiral naphthalimide dye (NTi). The resulting emit inverted CPL signal compared from L/D-HP enantiomers. After thermal annealing at 120 °C, this kind L/D-HP-NTi 1:1 molar ratio shows regular and ordered helical nanofibers arranged through intermolecularly layered packing accompanied further amplified effect (|gem | = 0.032, λem 535 nm). Significantly, non-doped CP-OLEDs based on device emitting layer (EML) exhibits low turn-on voltage (Von ) 4.7 V, high maximum brightness (Lmax 2001 cd m-2 , moderate external quantum efficiency (EQEmax 2.3%, as well excellent electroluminescence (CP-EL) (|gEL 0.023, 533

Язык: Английский

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