Molecular Carbon Imides

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(33), P. 14976 - 14991

Published: July 29, 2022

The creation and development of new forms nanocarbons have fundamentally transformed the scientific landscape in past three decades. As members nanocarbon family with accurate size, shape, edge structure, molecular carbon imides (MCIs) shown unexpected unique properties. Particularly, imide functionalization strategy has endowed these rylene-based carbons fascinating characteristics involving flexible syntheses, tailor-made structures, diverse properties, excellent processability, good stability. This Perspective elaborates design evolution to functional landscapes, illustrative examples are given, including a promising library multi-size multi-dimensional MCIs rigidly conjugated π-architectures, ranging from 1D nanoribbon 2D nanographene cross-dimensional MCIs. Although researchers achieved substantial progress using as components for exploration charge transport, photoelectric conversion, chiral luminescence performances, they far unleashing their full potential. Developing highly efficient regioselective coupling/ring-closure reactions formation multiple C–C bonds annulation electron-deficient aromatic units is crucial. Prediction by theory help machine learning artificial intelligence research along reliable nanotechnology characterization will give an impetus blossom related fields. Future investigations also advance toward─or even focus on─the emerging potential functions, especially fields electronics spin electronics, which expected open avenues.

Language: Английский

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B‐N Covalent Bond Embedded Double Hetero‐[n]helicenes for Pure Red Narrowband Circularly Polarized Electroluminescence with High Efficiency and Stability

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(5)

Published: Sept. 12, 2023

Chiral B/N embedded multi-resonance (MR) emitters open a new paradigm of circularly polarized (CP) organic light-emitting diodes (OLEDs) owing to their unique narrowband spectra. However, pure-red CP-MR and devices remain exclusive in literature. Herein, by introducing B-N covalent bond lower the electron-withdrawing ability para-positioned B-π-B motif, first pair double hetero-[n]helicenes (n = 6 7) emitter peaking 617 nm with small full-width at half-maximum 38 high photoluminescence quantum yield ≈100% toluene is developed. The intense mirror-image CP light produced enantiomers characterized dissymmetry factors (g

Language: Английский

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Helical Synthetic Nanographenes with Atomic Precision

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(3), P. 363 - 373

Published: Jan. 26, 2023

ConspectusUnderstanding and harnessing the properties of nanoscale molecular entities are considered as new frontiers in basic chemistry. In this regard, synthetic nanographene with atomic precision has attracted much attention recently. For instance, taking advantage marvelous bonding capability carbon, flat, curved, ribbon-type, or cone-shaped nanographenes have been prepared highly controllable elegant manner, allowing one to explore fascinating architectures intriguing optical, electrochemical, magnetic characteristics. This stands stark contrast other carbon-rich nanomaterials, such graphite oxides carbon quantum dots, which preclude thorough investigations because complicate structural defects. Undoubtedly, contributes strongly modern aromatic chemistry represents a vibrant field that may deliver transforming functional materials crucial for optoelectronics, nanotechnologies, biomedicine.Nonetheless, many cases, synthesis characterization compounds demanding. Low solubility, high strain, undesired selectivity, well incomplete excessive C-C bond formation common impediments, require formidable efforts control geometry, modulate edge structure, achieve accurate doping, push upper size boundary. These endeavors indispensable establishing structure-property relationships, lay down foundation exploring at level sophistications.In Account, we summarize our contributions by presenting series helical nanographenes, hexapole [7]helicene (H7H), nitrogen-doped H7H, [9]helicene (H9H), superhelicene, supertwistacene. kind giant reaches domain albeit precise structure. It provides unique platform study chirality nanoscale. We discuss methods point out, particular, strengths pitfalls Scholl oxidation, expected be valuable making general. addition, illustrate their exciting electrochemical photophysical performance, include, but not limited to, reversible multielectron redox chemistry, record panchromatic absorption, impressive photothermal behavior, extremely strong Cotton effect. unusual characteristics convincingly traced back three-dimensional conjugated architectures, highlighting critical roles π-electron delocalization, heteroatom-doping, substitution, symmetry determining nanographenes' functions. Lastly, put forward understanding on challenges opportunities lies ahead hope Account will inspire ever more ambitious achievements from attractive area research.

Language: Английский

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Functionalized Phenanthrene Imide‐Based Polymers for n‐Type Organic Thin‐Film Transistors

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(17)

Published: March 6, 2024

Abstract High‐performing n‐type polymers are crucial for the advance of organic electronics field, however strong electron‐deficient building blocks with optimized physicochemical properties constructing them still limited. The imide‐functionalized polycyclic aromatic hydrocarbons ( PAH s) extended π‐conjugated framework, high electron deficiency and good solubility serve as promising candidates developing high‐performance polymers. Among s, phenanthrene PhA ) features a well‐delocalized π‐system multiple modifiable active sites . However, ‐based imides seldom studied, mainly attributed to synthetic challenge. Herein, we report two functionalized CPOI CPCNI , by simultaneously incorporating imide carbonyl or dicyanomethylene onto Notably, dicyanomethylene‐modified exhibits well stabilized LUMO energy level (−3.84 eV), synergetic inductive effect from cyano groups. Subsequently, based on PCPOI‐Tz PCPCNI‐Tz were developed. Applied thin‐film transistors, owing electron‐deficiency polymer shows an improved mobility largely decreased threshold voltage compared This work affords structurally novel highlights effectiveness dual functionalization s electron‐withdrawing groups devising

Language: Английский

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Synthesis of Highly Luminescent Chiral Nanographene

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 62(4)

Published: Nov. 26, 2022

Chiral nanographenes with both high fluorescence quantum yields (ΦF ) and large dissymmetry factors (glum are essential to the development of circularly polarized luminescence (CPL) materials. However, most studies have been focused on improvement glum , whereas how design highly emissive chiral is still unclear. In this work, we propose a new strategy achieve ΦF by helical π-extension strongly luminescent chromophores while maintaining frontier molecular orbital (FMO) distribution pattern. nanographene perylene as core two dibenzo[6]helicene fragments wings has synthesized, which exhibits record 93 % among reported excellent CPL brightness (BCPL 32 M-1 cm-1 .

Language: Английский

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Synthesis of a π‐Extended Double [9]Helicene

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(18)

Published: March 2, 2023

Double helicenes are appealing chiral frameworks. Their π-extension is desirable to achieve (chir)optical response in the visible and near-infrared (NIR) region, but access higher double [n]helicenes (n≥8) has remained challenging. Herein, we report an unprecedented π-extended [9]helicene (D9H), unambiguously revealing its structure by single-crystal X-ray diffraction. D9H shows remarkable NIR emission from 750 1100 nm with a high photoluminescence quantum yield of 18 %. In addition, optically pure exhibits panchromatic circular dichroism notable dissymmetry factor (gCD ) 0.019 at 590 nm, which among highest region for reported helicenes.

Language: Английский

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Molecular Carbons: How Far Can We Go?

ACS Nano, Journal Year: 2023, Volume and Issue: 17(21), P. 20734 - 20752

Published: Oct. 27, 2023

The creation and development of carbon nanomaterials promoted material science significantly. Bottom-up synthesis has emerged as an efficient strategy to synthesize atomically precise nanomaterials, namely, molecular carbons, with various sizes topologies. Different from the properties feasibly obtained mixture numerous single-component carbons have been discovered owing their well-defined structures well potential applications in fields. This Perspective introduces recent advances derived fullerene, graphene, nanotube, carbyne, graphyne, Schwarzite acquired different strategies. By selecting a variety representative examples, we elaborate on relationship between nanomaterials. We hope these multiple points view presented may facilitate further advancement this field.

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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Highly Luminescent Chiral Double π-Helical Nanoribbons

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(8), P. 5295 - 5304

Published: Feb. 16, 2024

Unveiling the mechanism behind chirality propagation and dissymmetry amplification at molecular level is of significance for development chiral systems with comprehensively outstanding chiroptical performances. Herein, we have presented a straightforward Cu-mediated Ullmann homocoupling approach to synthesize perylene diimide-entwined double π-helical nanoribbons encompassing dimer, trimer, tetramer while producing homochiral or heterochiral linking centers. A significant was achieved, absorption factors (|gabs|) increasing from 0.009 0.017 further 0.019, luminescence (|glum|) rising 0.007 0.013 eventually 0.015 oligomers. The disparity magnetic transition dipole moment (m) densities in tetramers by time-dependent density functional theory calculations confirmed that oligomerization can maximize total m, which favorable achieving ever-increasing g factors. Notably, these π-helices exhibited exceptional photoluminescence quantum yields (ΦPL) ranging 83 95%. circularly polarized brightness (BCPL) reached remarkable 575 M–1 cm–1 tetramer, among highest values reported small molecules. This kind linearly extended offers platform comprehensive understanding amplification.

Language: Английский

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Nonalternant Nanographenes Containing N-Centered Cyclopenta[ef]heptalene and Aza[7]Helicene Units

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(23), P. 16161 - 16172

Published: May 9, 2024

Introducing helical subunits into negatively curved π-systems has a significant effect on both the molecular geometry and photophysical properties; however, synthesis of these embedded with nonbenzenoid remains challenging due to high strain deriving from curvature helix. Here, we report family nonalternant nanographenes containing nitrogen (N)-doped cyclopenta[ef]heptalene unit. Among them, CPH-2 CPH-3 can be viewed as hybrids benzoannulated aza[7]helicene. The crystal structures revealed saddle for CPH-1, saddle-helix hybrid CPH-2, twist-helix CPH-3. Experimental measurements theoretical calculations indicate that moieties in CPHs undergo flexible conformational changes at room temperature, while aza[7]helicene subunit exhibits dramatically increased racemization energy barrier (78.2 kcal mol–1 143.2 CPH-3). combination lone electron pairs N-doped unit twisted helix fragments results rich photophysics distinctive fluorescence phosphorescence CPH-1 similar Both enantiopure display distinct circular dichroism (CD) signals UV–vis range. Notably, compared reported fully π-extended nanographenes, excellent chiroptical properties |gabs| value 1.0 × 10–2 |glum| 7.0 10–3; values are among highest nanographenes.

Language: Английский

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