Palladium-catalyzed asymmetric hydrophosphination of internal alkynes: Atroposelective access to phosphine-functionalized olefins

Chem, Год журнала: 2022, Номер 8(12), С. 3346 - 3362

Опубликована: Сен. 23, 2022

Язык: Английский

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Synergistic Pd/Cu-Catalyzed 1,5-Double Chiral Inductions

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(13), С. 9241 - 9251

Опубликована: Март 19, 2024

Much attention has been focused on the catalytic asymmetric creation of single chiral centers or two adjacent stereocenters. However, construction nonadjacent stereocenters is significant importance but challenging because lack remote induction models. Herein, based a C═C bond relay strategy, we report synergistic Pd/Cu-catalyzed 1,5-double model. All four stereoisomers target products bearing 1,5-nonadjacent involving both allenyl axial and central chirality could be obtained divergently by simply changing combination catalysts with different configurations. Control experiments DFT calculations reveal novel mechanism 1,5-oxidative addition, contra-thermodynamic η3-allyl palladium shift, conjugate nucleophilic substitution, which play crucial roles in control reactivity, regio-, enantio-, diastereoselectivity. It expected that this strategy may provide general protocol for synthesis structural motifs distant

Язык: Английский

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Copper‐Phosphido Catalysis: Enantioselective Addition of Phosphines to Cyclopropenes**

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(36)

Опубликована: Июнь 19, 2023

We describe a copper catalyst that promotes the addition of phosphines to cyclopropenes at ambient temperature. A range cyclopropylphosphines bearing different steric and electronic properties can now be accessed in high yields enantioselectivities. Enrichment phosphorus stereocenters is also demonstrated via Dynamic Kinetic Asymmetric Transformation (DyKAT) process. combined experimental theoretical mechanistic study supports an elementary step featuring insertion Cu

Язык: Английский

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Ni-catalyzed propargylic substitution reaction: A general and versatile tool to assemble axially chiral phosphorus-containing allenes

Chem Catalysis, Год журнала: 2024, Номер 4(3), С. 100903 - 100903

Опубликована: Фев. 1, 2024

Язык: Английский

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Novel Stereo‐Induction Pattern in Pudovik Addition/Phospha‐Brook Rearrangement Towards Chiral Trisubstituted Allenes

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(22)

Опубликована: Март 23, 2024

Abstract Despite the significance of chiral allene skeletons in catalysis, organic synthesis and medicinal chemistry et al., there is a scarcity reports on axially allenyl phosphorus compounds. Here, we disclosed an efficient straightforward cascade reaction between ethynyl ketones phosphine oxides, resulting broad array trisubstituted allenes incorporating moiety high yields with excellent stereoselectivities facilitated by peptide‐mimic phosphonium salt (PPS) Additionally, comprehensive series mechanistic experiments have been conducted to elucidate that this proceeds via asymmetric Pudovik addition followed subsequent phospha ‐Brook rearrangement occurs concomitantly kinetic resolution, representing stereospecific protonation process facilitating central‐to‐axial chirality transfer manner. We anticipate our research will pave way for promising exploration novel stereo‐induction pattern addition/ reaction.

Язык: Английский

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Stereoselective synthesis of substituted 1,3-dienes from propargylic esters: electrophilic-metal or redox catalysis?

Science China Chemistry, Год журнала: 2024, Номер 67(5), С. 1384 - 1396

Опубликована: Март 22, 2024

Язык: Английский

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Visible-Light-Induced Regioselective Radical-Polar Crossover 1,4-Hydrophosphinylation of 1,3-Enynes: Access to Trisubstituted Allenes Bearing a Phosphine Oxide Group

Organic Letters, Год журнала: 2024, Номер 26(22), С. 4678 - 4683

Опубликована: Май 24, 2024

The radical 1,4-functionalizations of 1,3-enynes have emerged as a powerful strategy for the synthesis multisubstituted allenes. However, phosphorus-centered radical-initiated transformations remain largely elusive. Herein, visible-light photoredox catalytic regioselective hydrophosphinylation with diaryl phosphine oxides phosphinoyl precursors has been realized. This protocol features mild conditions, wide substrate scope, and good functional group tolerance, producing diverse range phosphinoyl-substituted allenes in moderate to yields high atom economy. Detailed mechanistic experiments revealed radical-polar crossover process reaction.

Язык: Английский

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Palladium-Catalyzed Allylic Alkylation Reactions of Nucleophilic Allenones: Asymmetric Allylic Alkylation, Z/E Divergent Allylic Alkylation, and [5 + 2] Annulation

ACS Catalysis, Год журнала: 2024, Номер 14(13), С. 9940 - 9954

Опубликована: Июнь 19, 2024

Metal-catalyzed allenylic substitution reactions where allenes serve as electrophilic precursors have been recognized a rapid way for novel allene construction. On the contrary, chemistry in which act nucleophiles has far less investigated, especially powerful platform such metal-catalyzed allylic alkylation reactions. We herein describe two unprecedented palladium-catalyzed of an nucleophile. In first reaction, using vinyloxazolidinones allyl precursor, asymmetric allylation trisubstituted allenones worked well to prepare array axially chiral tetrasubstituted allenes. Mechanistic studies and density functional theory (DFT) calculations indicated that weak hydrogen-bonding interaction between acidic C(sp2)–H allenone nitrogen anion π-azaallyl-Pd species is key success stereocontrol. This reaction revealed intriguing reactivity nucleophilic time. second with use allenylethylene carbonates π-oxyallyl-Pd precursors, presented unique under different conditions provide divergent synthetic access (E)- (Z)-allenyl diene products. Interestingly, subsequent sequential intramolecular cyclization/isomerization (Z)-product delivered dihydrooxepine derivatives [5 + 2] annulation

Язык: Английский

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Enantioselective Synthesis of Dihydropyrazoles by Palladium/Xu‐Phos‐Catalyzed Alleneamination of β,γ‐Unsaturated Hydrazones with Propargylic Acetates

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(20)

Опубликована: Март 10, 2023

The palladium-catalyzed asymmetric carboamination reaction is one of the most significant transformations in organic chemistry. Herein, we report first alleneamination β,γ-unsaturated hydrazones with propargylic acetates. This protocol enables efficient installation various multisubstituted allene groups onto dihydropyrazoles good yields excellent enantioselectivities. chiral sulfinamide phosphine ligand Xu-5 exhibits highly stereoselective control this protocol. salient features include readily available starting materials, a broad substrate scope, an easy scale-up, mild conditions and versatile transformations.

Язык: Английский

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Photoredox cobalt-catalyzed regio-, diastereo- and enantioselective propargylation of aldehydes via propargyl radicals

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Авг. 10, 2023

Catalytic enantioselective introduction of a propargyl group constitutes one the most important carbon-carbon forming reactions, as it is versatile to be transformed into diverse functional groups and frequently used in synthesis natural products biologically active molecules. Stereoconvergent transformations racemic precursors single enantiomer via radicals represent powerful strategy provide new reactivity. However, only few Cu- or Ni-catalyzed protocols have been developed with limited reaction modes. Herein, photoredox/cobalt-catalyzed regio-, diastereo- addition aldehydes presented, enabling construction broad scope homopropargyl alcohols that are otherwise difficult access high efficiency stereoselectivity from carbonates. Mechanistic studies DFT calculations provided evidence for involvement radicals, origin stereoconvergent process stereochemical models.

Язык: Английский

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