Recent Progress toward the Construction of Axially Chiral Molecules Catalyzed by an N-heterocyclic Carbene

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(20), P. 12520 - 12531

Published: Sept. 28, 2021

Axial chirality widely exists in natural products, pharmaceutical compounds, and other functional molecules; these axially chiral compounds also find wide utility as catalysts or ligands organic synthetic chemistry. Nevertheless, whereas significant progress has been made toward the synthesis of enantioenriched molecules over past two decades, strategies involving organocatalysis have only started to emerge recently. N-heterocyclic carbene (NHC) organocatalysts recognized be powerful tools for rapid construction complex molecular architectures. However, previous works mainly focused on assembly point recently it realized that asymmetric axial could achieved by using NHCs organocatalysts. This Perspective highlights developments advances scaffolds catalyzed NHCs. The aim this is provide an overview area serve a stepping stone future investigations.

Language: Английский

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Atroposelective Synthesis of Conjugated Diene-Based Axially Chiral Styrenes via Pd(II)-Catalyzed Thioether-Directed Alkenyl C–H Olefination

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(31), P. 12335 - 12344

Published: Aug. 3, 2021

The efficient stereoselective synthesis of conjugated dienes, especially those with axial chirality, remains a great challenge. Herein, we report the highly atroposelective axially chiral styrenes 1,3-diene scaffold via Pd(II)-catalyzed thioether-directed alkenyl C-H olefination strategy. This strategy features easy operation, mild reaction conditions, high functional group tolerance (69 examples), complete Z-selectivity, and excellent enantioselectivities (up to 99% ee). Notably, enantioselective atropisomers two stereogenic axes were also achieved using this ee 97:3 dr). Moreover, could be scaled up, resulting easily oxidized into sulfoxide derivatives diastereoselectivities, which showed promise as new type sulfur-olefin ligand.

Language: Английский

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Enantioselective Synthesis of Nitrogen–Nitrogen Biaryl Atropisomers via Copper-Catalyzed Friedel–Crafts Alkylation Reaction

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(37), P. 15005 - 15010

Published: Sept. 8, 2021

Nitrogen–nitrogen bonds containing motifs are ubiquitous in natural products and bioactive compounds. However, the atropisomerism arising from a restricted rotation around an N–N bond is largely overlooked. Here, we describe method to access first enantioselective synthesis of biaryl atropisomers via Cu-bisoxazoline-catalyzed Friedel–Crafts alkylation reaction. A wide range axially chiral bisazaheterocycle compounds were efficiently prepared high yields with excellent enantioselectivities desymmetrization kinetic resolution. Heating experiments showed that have rotational barriers.

Language: Английский

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Transition Metal-Catalyzed Biaryl Atropisomer Synthesis via a Torsional Strain Promoted Ring-Opening Reaction

Accounts of Chemical Research, Journal Year: 2022, Volume and Issue: 55(12), P. 1620 - 1633

Published: June 1, 2022

ConspectusArising from the restricted rotation of a single bond caused by steric or electronic effects, atropisomerism is one few fundamental categories for molecules to manifest their three-dimensional characters into which axially chiral biaryl compounds fall. Despite widespread occurrence skeletons in natural products, bioactive molecules, and ligands/organocatalysts, catalytic asymmetric methods synthesis these structures still lag behind demand. Major challenges preparation biaryls include accessing highly sterically hindered variants while controlling stereoselectivity. A couple useful strategies have emerged direct last two decades.Recently, we engaged atropisomers via transition metal catalysis, including ring-openings dibenzo cyclic compounds. During studies, serendipitously discovered that substituents adjacent axis cause be distorted minimize repulsion. The display higher reactivity ring-opening reactions than non-distorted molecules. In other words, torsional strain can promote reaction. On basis this concept, successfully realized reaction diaryliodoniums, silanes, 9H-fluoren-9-ols, delivered several differently substituted ortho tetra-substituted high enantioselectivity. not only activates substrates toward under mild conditions but also changes chemoselectivity bond-breaking events. palladium-catalyzed carboxylation S-aryl dibenzothiophenium, inversed selectivity exocyclic C–S cleavage reaction.In Account, summarize our studies on copper-, rhodium-, as collection straightforward with enantiopurity above-mentioned strain-promoted coupling strategy. part, energies are discussed aid density functional theory (DFT) calculations.

Language: Английский

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Rational design and atroposelective synthesis of N–N axially chiral compounds

Chem, Journal Year: 2021, Volume and Issue: 7(10), P. 2743 - 2757

Published: Aug. 18, 2021

Language: Английский

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Covalent organic framework atropisomers with multiple gas-triggered structural flexibilities

Nature Materials, Journal Year: 2023, Volume and Issue: 22(5), P. 636 - 643

Published: April 10, 2023

Language: Английский

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Rhodium-Catalyzed Asymmetric C–H Functionalization Reactions

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(16), P. 10079 - 10134

Published: Aug. 1, 2023

This review summarizes the advancements in rhodium-catalyzed asymmetric C–H functionalization reactions during last two decades. Parallel to rapidly developed palladium catalysis, rhodium catalysis has attracted extensive attention because of its unique reactivity and selectivity reactions. In recent years, Rh-catalyzed have been significantly many respects, including catalyst design, reaction development, mechanistic investigation, application synthesis complex functional molecules. presents an explicit outline catalysts ligands, mechanism, scope coupling reagents, applications.

Language: Английский

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Catalytic Asymmetric Synthesis of Axially Chiral 3,3'‐Bisindoles by Direct Coupling of Indole Rings

Chinese Journal of Chemistry, Journal Year: 2022, Volume and Issue: 40(18), P. 2151 - 2160

Published: May 31, 2022

Comprehensive Summary A new strategy for the enantioselective synthesis of axially chiral 3,3'‐bisindoles was devised by direct coupling two indole rings. This makes use C3‐umpolung reactivity 2‐indolylmethanols, which enables catalytic asymmetric addition reaction 2‐indolylmethanols with rationally designed 2‐substituted indoles, thus constructing 3,3'‐bisindole scaffolds in overall excellent yields (up to 98%) high enantioselectivities 96 : 4 er). approach not only has overcome challenges five‐five‐membered heterobiaryls, but also represents a application catalysis. More importantly, this class can undergo variety post‐functionalizations give 3,3'‐bisindole‐based organocatalysts, have found their preliminary applications

Language: Английский

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Cobalt-Catalyzed Enantioselective C–H Arylation of Indoles

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(2), P. 798 - 806

Published: Jan. 10, 2022

Atropoisomeric (hetero)biaryls are scaffolds with increasing importance in the pharmaceutical and agrochemical industries. Although it is most obvious disconnection to construct such compounds, direct enantioselective C–H arylation through concomitant induction of chiral information remains extremely challenging uncommon. Herein, unprecedented earth-abundant 3d-metal-catalyzed atroposelective reported, furnishing rare atropoisomeric C2-arylated indoles. Kinetic studies DFT computation revealed an uncommon mechanism for this asymmetric transformation, oxidative addition being rate- enantio-determining step. Excellent stereoselectivities were reached (up 96% ee), while using unusual N-heterocyclic carbene ligand bearing essential remote substituent. Attractive dispersion interactions along positive C–H---π exerted by identified as key factors guarantee excellent enantioselection.

Language: Английский

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Construction of axial chirality via asymmetric radical trapping by cobalt under visible light

Nature Catalysis, Journal Year: 2022, Volume and Issue: 5(9), P. 788 - 797

Published: Sept. 15, 2022

Language: Английский

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