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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Recent advances in Pd-catalyzed asymmetric cyclization reactions

Chemical Society Reviews, Journal Year: 2023, Volume and Issue: 53(2), P. 883 - 971

Published: Dec. 18, 2023

This review aims to collect advancements in enantioselective palladium-catalyzed cyclization reactions over the past eleven years, and it is organized into thirteen sections depending on different types of transformations involved.

Language: Английский

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Enantioselective synthesis of chiral quinohelicenes through sequential organocatalyzed Povarov reaction and oxidative aromatization

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: June 8, 2023

Heterohelicenes are of increasing importance in the fields materials science, molecular recognition, and asymmetric catalysis. However, enantioselective construction these molecules, especially by organocatalytic methods, is challenging, few methods available. In this study, we synthesize enantioenriched 1-(3-indol)-quino[n]helicenes through chiral phosphoric acid-catalyzed Povarov reaction followed oxidative aromatization. The method has a broad substrate scope offers rapid access to an array quinohelicenes with enantioselectivities up 99%. Additionally, photochemical electrochemical properties selected explored.

Language: Английский

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Enantioselective synthesis of [4]helicenes by organocatalyzed intermolecular C-H amination

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Jan. 25, 2024

Abstract Catalytic asymmetric synthesis of helically chiral molecules has remained an outstanding challenge and witnessed fairly limited progress in the past decades. Current methods to construct such compounds almost entirely rely on catalytic enantiocontrolled fused-ring system extension. Herein, we report a direct terminal peri -functionalization strategy, which allows for efficient assembling 1,12-disubstituted [4]carbohelicenes via organocatalyzed enantioselective amination reaction 2-hydroxybenzo[ c ]phenanthrene derivates with diazodicarboxamides. The key feature this approach is that stereochemical information catalyst could be transferred into not only helix sense but also remote C-N axial chirality products, thus enabling [4]- [5]helicenes both structural diversity complexity good efficiency excellent enantiocontrol. Besides, large-scale preparations representative transformations helical products further demonstrate practicality protocol. Moreover, DFT calculations reveal hydrogen bonds C-H---π interactions between substrates contribute ideal control.

Language: Английский

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Helicoselective Synthesis of Indolohelicenoids through Organocatalytic Central‐to‐Helical Chirality Conversion

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(9)

Published: Jan. 10, 2024

We report the helicoselective and convergent construction of indolohelicenoids with excellent efficiency stereocontrol. This reaction proceeds through a chiral-phosphoric-acid-catalyzed enantioselective cycloaddition eliminative aromatization sequence, which can be finely controlled by adjusting temperature. Mechanistic studies reveal that chiral phosphoric acid cooperatively serves as both bifunctional Brønsted catalyst, enabling one-pot central-to-helical chirality conversion. Additionally, optical properties synthesized were characterized to explore their potential applications in organic photoelectric materials.

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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Electrochemical Synthesis of Hetero[7]helicenes Containing Pyrrole and Furan Rings via an Oxidative Heterocoupling and Dehydrative Cyclization Sequence

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(3), P. 373 - 380

Published: Jan. 11, 2023

Abstract The electrochemical synthesis of hetero[7]helicenes including pyrrole and furan rings has been established. A single operation led to an oxidative heterocoupling dehydrative cyclization sequence afford oxaza[7]helicenes in 50–86% yields with 45–77% Faradic efficiencies. Their derivatization chiroptical properties were also investigated. magnified image

Language: Английский

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Copper-catalyzed modular synthesis of aromatic-interrupted Aza[6]helicenes with chiroptical properties

Cell Reports Physical Science, Journal Year: 2025, Volume and Issue: unknown, P. 102370 - 102370

Published: Jan. 1, 2025

Language: Английский

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Recent development of azahelicenes showing circularly polarized luminescence

Chemical Communications, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

This feature article summarizes the recent developments of azahelicenes showing circularly polarized luminescence.

Language: Английский

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Catalytic asymmetric construction of helicenes via transformation of biaryls

Organic & Biomolecular Chemistry, Journal Year: 2024, Volume and Issue: 22(16), P. 3186 - 3197

Published: Jan. 1, 2024

This review showcases a systematic overview of the available tools for catalytic asymmetric transformation biaryl substrates toward construction challenging enantioenriched helicenes and conceptual aspects associated with each type transformation. Depending on properties nature process, several methodologies have been developed, including olefin metathesis, hydroarylation alkynes, C-X (X = C, O, N) coupling, C-H functionalization. Pioneering studies an array representative reactions are discussed to underscore potential these synthetic protocols.

Language: Английский

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