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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Enantiodivergent Desymmetrization in the Rhodium(III)‐Catalyzed Annulation of Sulfoximines with Diazo Compounds

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(47), P. 15534 - 15538

Published: Oct. 11, 2018

RhIII - and IrIII -catalyzed asymmetric C-H functionalization reactions of arenes have relied on the employment chiral /IrIII cyclopentadienyl catalysts, introduction carboxylic acids to achiral Cp*RhX2 integration both strategies. Despite considerable progress, each reaction only provided a specific configuration enantioenriched product when using particular catalyst. Reported in this work is enantiodivergent coupling sulfoximines with various diazo compounds by desymmetrizing annulation. The enantiodivergence was enabled judicious choice acids, enantioselectivity correlates steric bias acid sulfoximine.

Language: Английский

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Manganese(I)‐Catalyzed Regio‐ and Stereoselective 1,2‐Diheteroarylation of Allenes: Combination of C−H Activation and Smiles Rearrangement

Angewandte Chemie International Edition, Journal Year: 2017, Volume and Issue: 56(33), P. 9939 - 9943

Published: June 20, 2017

Abstract Heteroarenes are important structural motif in functional molecules. A Mn I ‐catalyzed 1,2‐diheteroarylation of allenes via a C−H activation/Smiles rearrangement cascade is presented. The reaction occurred under additive‐free or even solvent‐free conditions, which allowed the creation two C−C and one C−N bonds single operation. series structurally diverse bicyclic tricyclic compounds bearing an exocyclic double bond were constructed good to excellent efficiency. decarboxylative ring‐opening products led facile synthesis vicinal biheteroaryls. Synthetic applications demonstrated preliminary mechanistic studies conducted.

Language: Английский

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A lesson for site-selective C–H functionalization on 2-pyridones: radical, organometallic, directing group and steric controls

Chemical Science, Journal Year: 2017, Volume and Issue: 9(1), P. 22 - 32

Published: Nov. 27, 2017

This minireview focuses on recent advances in site-selective C–H functionalization 2-pyridone which is an important heterocyclic motif medicinal and pharmaceutical chemistry.

Language: Английский

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Synthesis of Chiral Aldehyde Catalysts by Pd‐Catalyzed Atroposelective C−H Naphthylation

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(33), P. 11464 - 11468

Published: June 13, 2019

Abstract Chiral aldehyde catalysis opens new avenues for the activation of simple amines. However, lack easy access to structurally diverse chiral catalysts has hampered development this cutting‐edge field. Herein, we report a Pd‐catalyzed atroposelective C−H naphthylation with 7‐oxabenzonorbornadienes preparation axially biaryls excellent enantioselectivities (up >99 % ee ). This reaction is scalable and robust, which serves as key step provide rapid through three‐step functionalization sequence. These aldehydes exhibit better activities than previously reported organocatalysts in asymmetric glycine derived amides dipeptides. Moreover, preliminary investigation also discloses that catalyst can effectively override intrinsic facial selectivity dipeptide substrates, showcasing strong induction ability type novel catalysts.

Language: Английский

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Nitrone Directing Groups in Rhodium(III)‐Catalyzed C−H Activation of Arenes: 1,3‐Dipoles versus Traceless Directing Groups

Angewandte Chemie International Edition, Journal Year: 2016, Volume and Issue: 55(49), P. 15351 - 15355

Published: Nov. 10, 2016

Abstract Functionalizable directing groups (DGs) are highly desirable in C−H activation chemistry. The nitrone DGs explored rhodium(III)‐catalyzed of arenes and couplings with cyclopropenones. N‐tert ‐butyl nitrones bearing a small ortho substituent coupled to afford 1‐naphthols, where the acts as traceless DG. In contrast, coupling bulky group follows acylation/[3+2] dipolar addition pathway give bicyclics. N‐arylnitrones same process but delivers different

Language: Английский

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Cp*Rh(III)/Bicyclic Olefin Cocatalyzed C–H Bond Amidation by Intramolecular Amide Transfer

Journal of the American Chemical Society, Journal Year: 2017, Volume and Issue: 139(18), P. 6506 - 6512

Published: April 18, 2017

A bicyclic olefin was discovered as a cocatalyst in Cp*Rh(III)-catalyzed C–H bond amidation proceeding by an intramolecular amide transfer N-phenoxyacetamide derivatives. Combining experimental and theoretical studies, we propose that the promotes Rh(III) intermediate to undergo oxidative addition into O–N form Rh(V) nitrenoid species subsequently direct add ortho position. The directing group plays dual role cleavable coordinating moiety well essential coupling partner for amidation. This methodology successfully applied late-stage diversification of natural products marketed drug under mild conditions.

Language: Английский

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Synthesis of indoles and quinazolines via additive-controlled selective C–H activation/annulation of N-arylamidines and sulfoxonium ylides

Chemical Communications, Journal Year: 2019, Volume and Issue: 55(28), P. 4039 - 4042

Published: Jan. 1, 2019

Selective synthesis of indoles and quinazolines was achieved through a precise control C–H activation/annulation by changing additives.

Language: Английский

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Direct Access to Cobaltacycles via C–H Activation: N-Chloroamide-Enabled Room-Temperature Synthesis of Heterocycles

Organic Letters, Journal Year: 2017, Volume and Issue: 19(19), P. 5348 - 5351

Published: Sept. 19, 2017

Cobaltacycle synthesis via C-H activation has been achieved for the first time, providing key mechanistic insight into cobalt catalytic chemistry. N-Chloroamides are used as a directing synthon cobalt-catalyzed room-temperature and construction of heterocycles. Alkynes coupling partners allow convenient access to isoquinolones, class synthetically pharmaceutically important compounds. The broad substrate scope enables diverse range substitution patterns be incorporated heterocyclic scaffold.

Language: Английский

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Rh(III)-Catalyzed Mild Coupling of Nitrones and Azomethine Imines with Alkylidenecyclopropanes via C–H Activation: Facile Access to Bridged Cycles

ACS Catalysis, Journal Year: 2018, Volume and Issue: 8(5), P. 4194 - 4200

Published: April 3, 2018

Bridged cycles are an important class of structural motif in various biologically active molecules. Rh(III)-catalyzed C–H activation nitrones and azomethine imines the context dipolar addition with alkylidenecyclopropanes (ACPs) have been realized. By taking advantage ring strain ACPs, reaction aryl delivered bridged [3.2.1] bicyclic isoxazolidines, afforded tricyclic pyrazolones under same conditions, where both nitrone imine act as a directing group. All reactions occurred mild conditions broad substrates scope, high efficiency, >20:1 diastereoselectivity. The synthetic applications this protocol also demonstrated.

Language: Английский

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