Enantio- and Diastereodivergent Construction of 1,3-Nonadjacent Stereocenters Bearing Axial and Central Chirality through Synergistic Pd/Cu Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(32), P. 12622 - 12632

Published: Aug. 5, 2021

In contrast to the widely explored methods for asymmetric synthesis of molecules bearing a single stereocenter or adjacent stereocenters, concurrent construction 1,3-stereogenic centers in an enantio- and diastereoselective manner remains challenge, especially acyclic systems. Herein, we report diastereodivergent 1,3-nonadjacent stereocenters allenyl axial central chirality through synergistic Pd/Cu-catalyzed dynamic kinetic allenylation with racemic allenylic esters. The protocol is suitable wide range substrates including challenging esters less sterically bulky substituents provided chiral products high levels diastereoselectivities (up >20:1 dr >99% ee). Furthermore, several representative transformations involving axial-to-central transfer were conducted, affording useful structural motifs containing nonadjacent manner.

Language: Английский

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Copper-catalyzed functionalization of enynes

Chemical Science, Journal Year: 2020, Volume and Issue: 11(42), P. 11380 - 11393

Published: Jan. 1, 2020

The copper-catalyzed functionalization of enyne derivatives has recently emerged as a powerful approach in contemporary synthesis. Enynes are versatile and readily accessible substrates that can undergo variety reactions to yield densely functionalized, enantioenriched products. In this perspective, we review transformations enynes, such boro- hydrofunctionalizations, copper-mediated radical difunctionalizations, cyclizations. Particular attention is given the regiodivergent 1,3-enynes, current mechanistic understanding processes.

Language: Английский

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Asymmetric desymmetrization of alkene-, alkyne- and allene-tethered cyclohexadienones using transition metal catalysis

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 50(1), P. 658 - 666

Published: Dec. 7, 2020

This review is covering the recent development of catalytic asymmetric domino reactions for desymmetrization alkene-, alkyne- and allene-tethered cyclohexadienones using transition metals chiral ligands.

Language: Английский

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Decarboxylative 1,4-carbocyanation of 1,3-enynes to access tetra-substituted allenes via copper/photoredox dual catalysis

Chemical Science, Journal Year: 2021, Volume and Issue: 12(34), P. 11316 - 11321

Published: Jan. 1, 2021

We disclose herein the first example of merging photoredox catalysis and copper for radical 1,4-carbocyanations 1,3-enynes. Alkyl N-hydroxyphthalimide esters are utilized as precursors, reported mild redox-neutral protocol has broad substrate scope remarkable functional group tolerance. This strategy allows synthesis diverse multi-substituted allenes with high chemo- regio-selectivities, also permitting late stage allenylation natural products drug molecules.

Language: Английский

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Synthesis of Chiral Endocyclic Allenes by Palladium‐Catalyzed Asymmetric Annulation Followed by Cope Rearrangement

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(24)

Published: March 25, 2022

Catalytic asymmetric synthesis of chiral endocyclic allenes remains a challenge in allene chemistry owing to unfavored tension and complex chirality. Here, we present new relay strategy merging Pd-catalyzed [3+2] annulation with enyne-Cope rearrangement, providing facile route 9-membered high efficiency enantioselectivity. Moreover, theoretical calculations experimental studies were performed illustrate the critical, but unusual Cope rearrangement that allows for complete central-to-axial chirality transfer.

Language: Английский

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Axial chirality reversal and enantioselective access to Si-stereogenic silylallene

Chem, Journal Year: 2023, Volume and Issue: 9(10), P. 2956 - 2970

Published: July 18, 2023

Language: Английский

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Enantio‐ and Diastereoselective Synthesis of Chiral Tetrasubstituted α‐Amino Allenoates Bearing a Vicinal All‐Carbon Quaternary Stereocenter with Dual‐Copper‐Catalysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(31)

Published: June 1, 2023

The skeletons of chiral tetrasubstituted allenes bearing a vicinal all-carbon quaternary stereocenter are importance but still challenging to synthesize. Herein, we report enantio- and diastereoselective γ-additions 1-alkynyl ketimines with dual-copper-catalysis under mild conditions, affording α-amino allenoates in high yields (up 99 % yield) excellent enantioselectivities ee) diastereoselectivities >20 : 1 dr). Importantly, the stereodivergent synthesis products was realized by asymmetric γ-addition reaction Grignard reagent promoted epimerization. Moreover, dual-copper-catalyzed reactions were smoothly applied gram-scale adopted introduce allenyl moieties into bioactive molecules. Mechanistic experiments density functional theory (DFT) calculations demonstrated that catalyzed double copper catalysts.

Language: Английский

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Challenging Task of Ni-Catalyzed Highly Regio-/Enantioselective Semihydrogenation of Racemic Tetrasubstituted Allenes via a Kinetic Resolution Process

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(11), P. 7419 - 7430

Published: March 6, 2024

The first earth-abundant transition metal Ni-catalyzed highly regio- and enantioselective semihydrogenation of racemic tetrasubstituted allenes via a kinetic resolution process as challenging task was well established. This protocol furnishes expedient access to diversity structurally important enantioenriched chiral allylic molecules with high regio-, enantio-, Z/E-selectivity. Remarkably, this proceeded one carbon–carbon double bond allenes, which regioselective complementary the Rh-catalyzed asymmetric version. Deuterium labeling experiments density functional theory (DFT) calculations were carried out reveal reasonable reaction mechanism explain regio-/stereoselectivity.

Language: Английский

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Nickel-Catalyzed Enantioconvergent and Diastereoselective Allenylation of Alkyl Electrophiles: Simultaneous Control of Central and Axial Chirality

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(11), P. 7173 - 7177

Published: March 6, 2024

In recent years, remarkable progress has been described in the development of methods that simultaneously control vicinal stereochemistry, wherein both stereochemical elements are central chirality; contrast, and axial chirality comparatively rare. Herein we report a chiral nickel catalyst achieves enantioconvergent diastereoselective coupling racemic secondary alkyl electrophiles with prochiral 1,3-enynes (in presence hydrosilane) to generate tetrasubstituted allenes bear an adjacent stereogenic center. A carbon–carbon carbon–hydrogen bond formed this process, which provides good stereoselectivity is compatible array functional groups.

Language: Английский

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Recent advances in the asymmetric transformations of achiral cyclohexadienones

Organic Chemistry Frontiers, Journal Year: 2020, Volume and Issue: 8(4), P. 825 - 843

Published: Dec. 21, 2020

This review describes recent developments in the asymmetric transformations of achiral cyclohexadienones, including enantioselective desymmetrization prochiral cyclohexadienones and kinetic resolution racemic cyclohexadienones.

Language: Английский

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