Atropisomers beyond the C–C axial chirality: Advances in catalytic asymmetric synthesis

Chem, Journal Year: 2022, Volume and Issue: 8(7), P. 1855 - 1893

Published: May 6, 2022

Language: Английский

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Organocatalytic Atroposelective Synthesis of N−N Axially Chiral Indoles and Pyrroles by De Novo Ring Formation

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(17)

Published: Jan. 26, 2022

Abstract The first highly atroposelective construction of N−N axially chiral indole scaffolds was established via a new strategy de novo ring formation. This makes use the organocatalytic asymmetric Paal–Knorr reaction well‐designed N ‐aminoindoles with 1,4‐diketones, thus affording ‐pyrrolylindoles in high yields and excellent atroposelectivities (up to 98 % yield, 96 ee). In addition, this is applicable for synthesis bispyrroles 97 More importantly, such heterocycles can be converted into organocatalysts applications catalysis, some molecules display potent anticancer activity. work not only provides but also offers members atropisomer family promising synthetic medicinal chemistry.

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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Organocatalytic Enantioselective Synthesis of Axially ChiralN,N′‐Bisindoles

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(15)

Published: Feb. 7, 2023

This study establishes the first organocatalytic enantioselective synthesis of axially chiral N,N'-bisindoles via phosphoric acid-catalyzed formal (3+2) cycloadditions indole-based enaminones as novel platform molecules with 2,3-diketoesters, where de novo indole-ring formation is involved. Using this new strategy, various were synthesized in good yields and excellent enantioselectivities (up to 87 % yield 96 ee). More importantly, class exhibited some degree cytotoxicity toward cancer cells was derived into phosphine ligands high catalytic activity. provides a strategy for using asymmetric organocatalysis realize applications such scaffolds medicinal chemistry catalysis.

Language: Английский

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Atroposelective Synthesis of 1,1′‐Bipyrroles Bearing a Chiral N−N Axis: Chiral Phosphoric Acid Catalysis with Lewis Acid Induced Enantiodivergence

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(16)

Published: Feb. 17, 2022

Abstract We present herein a highly efficient atroposelective synthesis of axially chiral 1,1′‐bipyrroles bearing an N−N linkage from simple hydrazine and 1,4‐diones. Further product derivatizations led to bifunctional compounds with high potential in asymmetric catalysis. For this chrial phosphoric acid (CPA)‐catalyzed double Paal–Knorr reaction, intriguing Fe(OTf) 3 ‐induced enantiodivergence was also observed.

Language: Английский

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Enantioselective Synthesis of N−N Bisindole Atropisomers

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(44)

Published: Sept. 15, 2022

N-N Atropisomers are a common motif in natural products and represent significant dimension for exploration modern pharmaceutical medicinal chemistry. However, the catalytic atroposelective synthesis of such molecules remains challenging, hampering meaningful development. In particular, an enantioselective bisindole atropisomers is unprecedented. Herein, first via palladium-catalyzed de novo construction one indole skeleton presented. A wide variety axially chiral bisindoles were generated good yields with excellent enantioselectivities cascade condensation/N-arylation reaction. Structurally diverse indole-pyrrole, indole-carbazole, non-biaryl-indole possessing axis accessed using this protocol. Moreover, investigations density functional theory (DFT) calculations provided insight into reaction mechanism enantiocontrol.

Language: Английский

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Enantioselective Synthesis of N−N Biaryl Atropisomers through Iridium(I)‐Catalyzed C−H Alkylation with Acrylates

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(37)

Published: May 4, 2023

Abstract Enantioselective synthesis of N−N biaryl atropisomers is an emerging area but remains underexplored. The development efficient in great demand. Herein, the construction through iridium‐catalyzed asymmetric C−H alkylation reported for first time. In presence readily available Ir precursor and Xyl‐BINAP, a variety axially chiral molecules based on indole‐pyrrole skeleton were obtained good yields (up to 98 %) with excellent enantioselectivity 99 % ee). addition, bispyrrole could also be synthesized enantioselectivity. This method features perfect atom economy, wide substrate scope, multifunctionalized products allowing diverse transformations.

Language: Английский

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Catalytic Asymmetric Synthesis of Atropisomers Featuring an Aza Axis

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(18), P. 2537 - 2554

Published: Sept. 11, 2023

ConspectusAtropisomers bearing a rotation-restricted axis are common structural units in natural products, chiral ligands, and drugs; thus, the prevalence of asymmetric synthesis has increased recent decades. Research into atropisomers featuring an N-containing (N-X atropisomers) remains its infancy compared with well-developed C-C atropisomer analogue. Notably, N-X could offer divergent scaffolds, which extremely important bioactive molecules. The is recognized as both appealing challenging. Recently, we devoted our efforts to catalytic atropisomers, benzimidazole-aryl N-C indole-aryl hydrogen-bond-assisted pyrrole-pyrrole N-N pyrrole-indole indole-indole atropisomers. To obtain Buchwald-Hartwig reaction amidines or enamines was employed. Using Pd(OAc)2/(S)-BINAP Pd(OAc)2/(S)-Xyl-BINAP catalyst system, were readily obtained. address issue reduced stability diarylamine axis, six-membered intramolecular N-H-O hydrogen bond introduced scaffold. A tandem N-arylation/oxidation process used for phosphoric acid (CPA)-catalyzed N-aryl quinone For copper-mediated Friedel-Crafts alkylation/arylation developed. desymmetrization completed successfully via Cu(OTf)2/chiral bisoxazoline (CuOTf)·Tol/bis(phosphine) dioxide thereby achieving first N/N bipyrrole Asymmetric amination utilized provide bisindole excellent stereogenic control. This scaffold using de novo indole construction strategy. heterobiaryl substantially facilitated palladium-catalyzed transient directing group (TDG)-mediated C-H functionalization. Atropisomeric alkenylation, allylation, alkynylation accomplished Pd(OAc)2/l-tert-leucine system. Herein, summarize work on palladium-, copper-, CPA-catalyzed syntheses Furthermore, application molecule analogues axially ligands demonstrated. Subsequently, briefly discussed terms single crystals obtained rotational barriers. Finally, outlook provided.

Language: Английский

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Enantioselective Synthesis of N‐N Atropisomers by Palladium‐Catalyzed C−H Functionalization of Pyrroles

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(21)

Published: March 21, 2023

The catalytic asymmetric construction of N-N atropisomeric biaryls remains a formidable challenge. Studies them lag far behind studies the more classical carbon-carbon biaryl atropisomers, hampering meaningful development. Herein, first palladium-catalyzed enantioselective C-H activation pyrroles for synthesis atropisomers is presented. Structurally diverse indole-pyrrole possessing chiral axis were produced with good yields and high enantioselectivities by alkenylation, alkynylation, allylation, or arylation reactions. Furthermore, kinetic resolution trisubstituted heterobiaryls sterically demanding substituents was also achieved. Importantly, this versatile functionalization strategy enables iterative exquisite selectivity, expediting formation valuable, complex, atropisomers.

Language: Английский

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Cobalt-catalyzed atroposelective C−H activation/annulation to access N−N axially chiral frameworks

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

Published: Aug. 29, 2023

The N-N atropisomer, as an important and intriguing chiral system, was widely present in natural products, pharmaceutical lead compounds, advanced material skeletons. anisotropic structural characteristics caused by its special axial rotation have always been one of the challenges that chemists strive to overcome. Herein, we report efficient method for enantioselective synthesis axially frameworks via a cobalt-catalyzed atroposelective C-H activation/annulation process. reaction proceeds under mild conditions using Co(OAc)2·4H2O catalyst with salicyl-oxazoline (Salox) ligand O2 oxidant, affording variety products high yields enantioselectivities. This protocol provides approach facile construction atropisomers further expands range derivatives. Additionally, electrocatalysis, desired were also successfully achieved good excellent efficiencies

Language: Английский

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