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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Organocatalytic Enantioselective Synthesis of Seven‐Membered Ring with Inherent Chirality

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(8)

Published: Jan. 8, 2024

Abstract Inherent chirality is used to describe chiral cyclic molecules devoid of central, axial, planar, or helical and has tremendous applications in recognition enantioselective synthesis. Catalytic divergent syntheses inherently have attracted increasing interest from chemists. Herein, we report the synthesis tribenzocycloheptene derivatives via phosphoric acid (CPA)‐catalyzed condensation ketones hydroxylamines. This chemistry paves way accessing less stable 7‐membered rings with inherent chirality. A series oxime ethers was synthesized good yields (up 97 %) excellent enantioselectivities 99 % ee).

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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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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Catalytic Enantioselective Synthesis of Inherently Chiral Molecules: Recent Advances

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(42)

Published: Sept. 2, 2023

Abstract Inherent chirality represents a distinct category of molecular that does not fall within the traditional classification four chiral elements: central, axial, planar, and helical chirality. While extensive research has been conducted on catalytic enantioselective construction these conventional chiralities, corresponding synthesis inherently molecules remained largely unexplored. This minireview provides comprehensive summary recent advancements in this field, focusing asymmetric calixarenes, saddle‐shaped tetraphenylenes their heterocycle derivatives, mechanically planar rotaxanes multilayer 3D frameworks, as well our perspective field.

Language: Английский

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Organocatalytic Dynamic Kinetic Resolution Enabled Asymmetric Synthesis of Phosphorus‐Containing Chiral Helicenes

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(49)

Published: Oct. 17, 2023

The catalytic asymmetric synthesis of phosphorus-containing helicenes remains a formidable challenge, presumably due to the lack rational design substrates, right choice reactions together with highly effective catalysis systems. Herein, we disclosed an efficient and practical DKR-involving (dynamic kinetic resolution) cascade strategy toward synthesizing novel family phosphorus-installing by peptide-mimic phosphonium salt (PPS) catalysis. sequential process PPS-catalyzed phospha-Michael attack copper salt-facilitated aromatization led formation unprecedented oxa[5]helicene scaffolds. A wide variety substrates bearing assortment functional groups were compatible this protocol, furnishing expected helical compounds in high yields excellent stereoselectivities. Additionally, products could be conveniently elaborated promising phosphine ligands perfectly retained chirality, which turned out chiral transition metal-catalyzed reactions. These findings not only expand current library but also offer insights explore other challenging scaffolds molecular chirality.

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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Atroposelective Synthesis of Heterobiaryls through Ring Formation

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(27)

Published: March 6, 2023

Atropisomeric heterobiaryls play a vital role in natural products, chiral ligands, organocatalysts, and other research fields, which have aroused great interest from chemists recent years. Until now, growing number of optically active based on indole, quinoline, isoquinoline, pyridine, pyrrole, azole, benzofuran skeletons been successfully synthesized through metal or organic catalytic cross-coupling, functionalization prochiral racemic heterobiaryls, ring formation. Among different strategies for the atroposelective synthesis strategy formation has become tool toward this goal. In review, we summarize enantioselective axially approaches, such as cycloaddition, cyclization, chirality conversion. Meanwhile, reaction mechanism corresponding applications are also discussed.

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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Padlocking dihydrofurannulation for the control of small degree of helicity built on a fused-tetracyclic core

Chemical Science, Journal Year: 2024, Volume and Issue: 15(19), P. 7300 - 7307

Published: Jan. 1, 2024

Enantioselective construction of small molecules displaying a configurationally stable helical shape built on fused-tetracyclic core is daunting synthetic challenge even more pronounced when five-membered rings are incorporated in the structure. The resulting higher configurational lability strongly hampers their access, and therefore development new efficient methodologies timely highly desirable. In this context, we describe padlocking approach

Language: Английский

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