Design and Catalytic Asymmetric Construction of Axially Chiral 3,3′‐Bisindole Skeletons

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(10), P. 3014 - 3020

Published: Nov. 21, 2018

Abstract The first catalytic asymmetric construction of 3,3′‐bisindole skeletons bearing both axial and central chirality has been established by organocatalytic addition reactions 2‐substituted 3,3′‐bisindoles with 3‐indolylmethanols (up to 98 % yield, all >95:5 d.r., >99 ee ). This reaction also represents the highly enantioselective axially chiral skeletons, utilizes strategy introducing a bulky group ortho ‐position prochiral 3,3′‐bisindoles. not only provides good example for simultaneously controlling in one operation, but serves as new backbones from substrates.

Language: Английский

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Enantioselective C(sp³)–H Amidation of Thioamides Catalyzed by a Cobalt^III/Chiral Carboxylic Acid Hybrid System

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(4), P. 1153 - 1157

Published: Nov. 27, 2018

Abstract Recent advances in Cp x M III catalysis (M=Co, Rh, Ir) have enabled a variety of enantioselective C(sp 2 )−H functionalization reactions, but 3 is still largely unexplored. We describe an asymmetric amidation thioamides using achiral Co /chiral carboxylic acid hybrid catalytic system, which provides easy and straightforward access to chiral β‐amino thiocarbonyl carbonyl building blocks with quaternary carbon stereocenter.

Language: Английский

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Chiral Cyclopentadienyl Ligands: Design, Syntheses, and Applications in Asymmetric Catalysis

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(24), P. 13198 - 13224

Published: July 16, 2020

The creation of new chiral ligands capable providing high stereocontrol in metal-catalyzed reactions is crucial modern organic synthesis. production bioactive molecules as single enantiomers increasingly required, and asymmetric catalysis with metal complexes constitutes one the most efficient synthetic strategies to access optically active compounds. Herein we offer a historical overview on development derivatives ubiquitous cyclopentadienyl ligand (CpX ), detail their successful application broad range transformations. Those include functionalization challenging C-H bonds beyond, giving an extensive catalogue valuable molecules. A critical comparison existing families, design, synthesis, complexation different metals also provided. In addition, future research directions are discussed further enhance performance CpX enantioselective catalysis.

Language: Английский

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Diverse Approaches for Enantioselective C−H Functionalization Reactions Using Group 9 Cp^xM^III Catalysts

Chemistry - A European Journal, Journal Year: 2020, Volume and Issue: 26(33), P. 7346 - 7357

Published: Jan. 29, 2020

Transition-metal-catalyzed C-H functionalization reactions with Cp*MIII catalysts (M=Co, Rh, Ir) have found a wide variety of applications in organic synthesis. Albeit the intrinsic difficulties achieving catalytic stereocontrol using these due to their lack additional coordination sites for external chiral ligands and conformational flexibility Cp ligand, enantioselective Group 9 metal triad Cp-type been intensively studied since 2012. In this minireview, progress according type catalyst used are summarized discussed. The development Cpx complexes thereof, artificial metalloenzymes, carboxylate-assisted activations, alkylations assisted by carboxylic acids or sulfonates, transient directing groups

Language: Английский

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Enantioselective Synthesis of Biaryl Atropisomers by Pd‐Catalyzed C−H Olefination using Chiral Spiro Phosphoric Acid Ligands

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(20), P. 6708 - 6712

Published: March 25, 2019

Abstract The discovery of proper ligands to simultaneously modulate the reactivity and effectively control stereoselectivity is a central topic in field enantioselective C−H activation. Herein, we reported synthesis axially chiral biaryls by Pd‐catalyzed atroposelective olefination. A novel spiro phosphoric acid, STRIP, was identified as superior ligand for this transformation. broad range quinoline derivatives were synthesized good yields with excellent enantioselectivities (up 98 % ee ). Density functional theory used gain theoretical understanding reaction.

Language: Английский

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Enantioselective Synthesis of Chiral‐at‐Sulfur 1,2‐Benzothiazines by Cp^xRh^III‐Catalyzed C−H Functionalization of Sulfoximines

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(47), P. 15539 - 15543

Published: Oct. 10, 2018

Abstract Sulfoximines with stereogenic sulfur atoms are attractive structural motifs in drug discovery. A direct catalytic enantioselective method for the synthesis of sulfur‐chiral 1,2‐benzothiazines from readily accessible diaryl sulfoximines is presented. Rhodium(III) complexes equipped chiral cyclopentadienyl ligands and paired suitable carboxylic acid additives engage an enantiodetermining C−H activation directed by sulfoximine group. Subsequent trapping rhodacycle a broad range diazoketones gives access to S‐chiral synthetically highly substitution patterns good yields enantioselectivities.

Language: Английский

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Enantioselective Synthesis of C−N Axially Chiral N‐Aryloxindoles by Asymmetric Rhodium‐Catalyzed Dual C−H Activation

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(20), P. 6732 - 6736

Published: March 20, 2019

The first enantioselective Satoh-Miura-type reaction is reported. A variety of C-N axially chiral N-aryloxindoles have been enantioselectively synthesized by an asymmetric rhodium-catalyzed dual C-H activation and alkynes. High yields enantioselectivities were obtained (up to 99 % yield up ee). To date, it also the example synthesis compounds such a strategy.

Language: Английский

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Pd‐Catalyzed Atroposelective C−H Allylation through β‐O Elimination: Diverse Synthesis of Axially Chiral Biaryls

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(52), P. 17151 - 17155

Published: Nov. 9, 2018

Abstract Biaryl atropisomers are of great importance in natural products, pharmaceuticals, and asymmteric synthesis. The efficient synthesis these chiral scaffolds with full enantiocontrol high diversity remains challenging. Reported herein is a Pd‐catalyzed atroposelective C−H allylation tert ‐leucine as an catalytic transient auxiliary. A wide range enantioenriched biaryl aldehydes were prepared synthetically useful yields excellent enantioselectivity (up to >99 % ee ) through β‐O elimination. reaction could be carried out on gram scale without erosion the value. variety axially carboxylic acids obtained enantiopurity. resulting might used asymmetric ligands and/or organocatalysts.

Language: Английский

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A Strategy for Synthesizing Axially Chiral Naphthyl‐Indoles: Catalytic Asymmetric Addition Reactions of Racemic Substrates

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(42), P. 15104 - 15110

Published: Aug. 23, 2019

Abstract A new strategy for enantioselective synthesis of axially chiral naphthyl‐indoles has been established through catalytic asymmetric addition reactions racemic with bulky electrophiles. Under phosphoric acid catalysis, azodicarboxylates and o ‐hydroxybenzyl alcohols served as but reactive electrophiles that were attacked by C2‐unsubstituted naphthyl‐indoles, which underwent a dynamic kinetic resolution to afford two series in good yields (up 98 %) high enantioselectivities 98:2 er).

Language: Английский

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Palladium‐Catalyzed Enantioselective Cacchi Reaction: Asymmetric Synthesis of Axially Chiral 2,3‐Disubstituted Indoles

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(5), P. 2105 - 2109

Published: Nov. 22, 2019

We report herein the first examples of a palladium-catalyzed enantioselective Cacchi reaction for synthesis indoles bearing chiral C2-aryl axis. In presence catalytic amount Pd(OAc)2 and (R,R)-QuinoxP* ligand, N-aryl(alkyl)sulfonyl-2-alkynylanilides with arylboronic acids under oxygen atmosphere afforded enantioenriched 2,3-disubstituted in high yields enantioselectivity. The indole ring is constructed de novo this process complexation-induced chirality transfer proposed to account observed

Language: Английский

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