The Scholl Reaction as a Powerful Tool for Synthesis of Curved Polycyclic Aromatics

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(18), P. 14554 - 14593

Published: Aug. 12, 2022

The past decade has witnessed remarkable success in the synthesis of curved polycyclic aromatics through Scholl reactions which enable oxidative aryl-aryl coupling even company with introduction significant steric strain. These are not only unique objects structural organic chemistry relation to nature aromaticity but also play an important role bottom-up approaches precise nanocarbons topology. Moreover, they have received considerable attention fields supramolecular and functional materials because their interesting properties promising applications. Despite great aromatics, outcome a newly designed substrate reaction still cannot be predicted generic manner largely due limited understanding on mechanism possible rearrangement processes. This review provides overview focus applications structures aims shed light key factors that affect synthesizing sterically strained aromatics.

Language: Английский

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Enantioselective Synthesis of Azahelicenes through Organocatalyzed Multicomponent Reactions

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(27)

Published: May 5, 2023

We have developed an efficient modular asymmetric synthesis of azahelicenes through organocatalyzed multicomponent reaction from readily available polycyclic aromatic amines, aldehydes, and (di)enamides, by employing a central-to-helical chirality conversion strategy. A series aza[5]- aza[4]helicenes bearing various substituents were afforded this one-pot sequential enantioselective Povarov reaction/oxidative aromatization process, with good yields high enantioselectivities. The fruitful diverse derivatizations the chiral azahelicene products demonstrated potential method, preliminary application derivative as organocatalyst was showcased. photophysical chiroptical properties these azahelicenes, particularly acid/base-triggered switching properties, also well studied, which may find applications in development novel organic optoelectronic materials.

Language: Английский

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Design and enantioselective synthesis of 3D π-extended carbohelicenes for circularly polarized luminescence

Nature Synthesis, Journal Year: 2024, Volume and Issue: 3(6), P. 774 - 786

Published: April 19, 2024

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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Electrochemical Syntheses of Polycyclic Aromatic Hydrocarbons (PAHs)

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(49)

Published: March 25, 2023

Polycyclic aromatic hydrocarbons (PAHs) have surfaced as increasingly viable components in optoelectronics and material sciences. The development of highly efficient atom-economic tools to prepare PAHs under exceedingly mild conditions constitutes a long-term goal. Traditional syntheses largely relied on multistep approaches or the conventional Scholl reaction. However, reactions are inefficient with electron-deficient substrates, require stoichiometric chemical oxidants, typically occur presence strong acid. In sharp contrast, electrochemistry has gained considerable momentum during past decade an alternative for facile straightforward assembly, generally via electro-oxidative dehydrogenative annulation, releasing molecular hydrogen sole byproduct by evolution This review provides overview recent significant advances field electrochemical various until January 2023.

Language: Английский

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Divergent asymmetric synthesis of heterohelicenes via sequential organocatalyzed Povarov reaction and aromatization

Cell Reports Physical Science, Journal Year: 2024, Volume and Issue: 5(6), P. 101993 - 101993

Published: May 27, 2024

Incorporating main-group elements into the backbone of chiral carbohelicenes can significantly alter their electronic and optical properties, which renders asymmetric synthesis heterohelicenes an appealing research field. Herein, we present divergent two distinct types from same starting material by employing key Povarov reaction with phosphoric acid catalysts. Specifically, one-pot reaction/oxidative aromatization yielded C1-ortho-phenol-substituted [5]/[6]pyridohelicenes, while subsequent Pd(II)/base-mediated furan formation resulted in longer [7]/[8]heterohelicenes bearing both pyridine moieties. Fruitful derivatizations helicenes, along promising photophysical chiroptical have underscored value this method.

Language: Английский

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Chalcogen-doped, (seco)-hexabenzocoronene-based nanographenes: synthesis, properties, and chalcogen extrusion conversion

Chemical Science, Journal Year: 2023, Volume and Issue: 14(33), P. 8905 - 8913

Published: Jan. 1, 2023

A series of chalcogen-doped nanographenes were obtained by insertion different chalcogens into the HBC or seco -HBC backbone. The chalcogen-dependent photophysical properties and chalcogen-extrusion reactions investigated.

Language: Английский

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Synthesis of Highly Luminescent Chiral Nanographene

Angewandte Chemie, Journal Year: 2022, Volume and Issue: 135(4)

Published: Nov. 26, 2022

Abstract Chiral nanographenes with both high fluorescence quantum yields ( Φ F ) and large dissymmetry factors g lum are essential to the development of circularly polarized luminescence (CPL) materials. However, most studies have been focused on improvement , whereas how design highly emissive chiral is still unclear. In this work, we propose a new strategy achieve 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 B 32 M −1 cm .

Language: Английский

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Electrochemical Continuous-Flow Scholl Reaction toward Polycyclic Aromatic Hydrocarbons

Organic Letters, Journal Year: 2024, Volume and Issue: 26(11), P. 2243 - 2248

Published: March 8, 2024

The preparation of polycyclic aromatic hydrocarbons (PAHs) by the Scholl reaction is typically performed using superstoichiometric oxidants. Herein, we develop an electrochemical continuous-flow to access PAHs that features a reduction in use supporting electrolytes and easy scale-up without changing conditions setups. This allows synthesis distorted containing three [5]helicene units possess intriguing electronic optical properties.

Language: Английский

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Double [8]Helicene Featuring a Dibenzo[g,p]chrysene Core: Synthesis and Chiroptical Response

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 2, 2025

Double [8]helicene 1, featuring a dibenzo[g,p]chrysene core, was synthesized via the Scholl reaction, and its structure unambiguously confirmed by single-crystal X-ray diffraction analysis of dicationic salt [1-Cl]2+·(SbCl6-)2. The compound exhibits red fluorescence with an emission maximum at 618 nm (λem) quantum yield 16.2%, highlighting potential in optoelectronic applications. Furthermore, circular dichroism (CD) circularly polarized luminescence (CPL) measurements reveal notable chiroptical activity, absorption dissymmetry factors |gabs| = 5.11 × 10-3 |glum| 7.1 10-4, respectively.

Language: Английский

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