Gold-Catalyzed Reactions of Specially Activated Alkynes, Allenes, and Alkenes

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(14), P. 8756 - 8867

Published: Nov. 23, 2020

This review describes the gold-catalyzed reactions of specially activated alkynes, allenes, and alkenes. Such species are characterized by presence either electron-donating or electron-withdrawing groups as substituents carbon π-system. They intrinsically polarized, when compared to their nonspecially counterparts can therefore be involved in transformations featuring increased regio-, stereo-, chemoselectivities. The chemistry π-systems under homogeneous gold catalysis is extremely rich varied. reactivity observed with unsaturated systems often transposed ones without loss efficiency. However, also exhibit specific reactivities that cannot attained regular substrates. In this family π-systems, ynamides analogs, along alkynyl carbonyl derivatives, classes substrates have retained most attention. provides an overview developed all discussing general reactivities, presenting commenting on well applications.

Language: Английский

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Asymmetric dearomatization catalysed by chiral Brønsted acids via activation of ynamides

Nature Chemistry, Journal Year: 2021, Volume and Issue: 13(11), P. 1093 - 1100

Published: Oct. 11, 2021

Language: Английский

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Synthesis of Axially ChiralN‐Arylindoles via Atroposelective Cyclization of Ynamides Catalyzed by Chiral Brønsted Acids

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(20)

Published: March 5, 2022

In recent years, asymmetric catalysis of ynamides has attracted much attention, but these reactions mostly constructed central chirality, except for a few examples on the synthesis axially chiral compounds which exclusively relied noble-metal catalysis. Herein, facile access to N-heterocycles enabled by Brønsted acid-catalyzed 5-endo-dig cyclization is disclosed, represents first metal-free protocol construction from ynamides. This method allows practical and atom-economical valuable N-arylindoles in excellent yields with generally enantioselectivities. Moreover, organocatalysts ligands based such N-arylindole skeletons are demonstrated be applicable

Language: Английский

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Lewis Acid Catalyzed Cycloaddition of Bicyclobutanes with Ynamides for the Synthesis of Polysubstituted 2‐Amino‐bicyclo[2.1.1]hexenes

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(32)

Published: May 24, 2024

Abstract Synthesis of bicyclic scaffolds has gained significant attention in drug discovery due to their potential mimic benzene bioisosteres. Here, we present a mild and scalable Sc(OTf) 3 ‐catalyzed [3+2] cycloaddition bicyclo[1.1.0]butanes (BCBs) with ynamides, yielding diverse array polysubstituted 2‐amino‐bicyclo[2.1.1]hexenes good excellent yields. These products offer valuable starting materials for the construction novel functionalized bicyclo[1.1.0]butanes. Preliminary mechanistic studies indicate that reaction involves nucleophilic addition ynamides bicyclo[1.1.0]butanes, followed by an intramolecular cyclization situ generated enolate keteniminium ion. We expect these findings will encourage utilization complex bioisosteres foster further investigation into BCB‐based chemistry.

Language: Английский

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Dirhodium-Catalyzed Asymmetric Transformations of Alkynes via Carbene Intermediates

Accounts of Chemical Research, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 31, 2025

ConspectusFunctionalization of alkynes is an established cornerstone organic synthesis. While numerous transition metals exhibit promising activities in the transformations via π-insertion or oxidative cyclometalation, Lewis π-acids offer a different approach. By coordinating with through π-bonding, facilitate nucleophilic addition, leading to formation alkenyl metal species. These species can undergo electron rearrangement generate carbenes, which are crucial intermediates for subsequent carbene transfer reactions. This reaction pathway provides versatile route alkyne functionalization, especially asymmetric manner. Although π-acid, gold(I), pioneered this mode, development variants remains challenging due linear coordination gold(I). Therefore, expanding range catalysts beyond gold(I) complexes other would further advances chiral molecule construction and exploration novel modes.In Account, we present concise review multifunctionalization dirhodium-catalyzed transformations, providing modulation strategies substrates plausible mechanisms. In aromatization-driven strategy, furanyl dirhodium generated from enynone, terminated by enantioselective intramolecular C-H insertion, cyclopropanation, aromatic substitution, Büchner reaction, giving dihydroindoles, dihydrobenzofurans, cyclopropane-fused tetrahydroquinolines, fluorenes, cyclohepta[b]benzofurans. The cap-tether strategy was developed study balance reactivity selectivity azo-enyne. gave first catalytic cycloisomerization azo-enyne, affording centrally axially isoindazole derivatives. synergistic activation i.e., EWG C-H···O interaction, introduced achieve enynes, cyclopropane-annulated bicyclic systems enynals. Benefiting these successes, difluoromethyl-substituted enynes were designed proven be effective substrates. With corresponding benzo-1,6-enynes as substrates, biscyclopropanation cascaded cyclopropanation/cyclopropenation achieved using dicarbene equivalents. Additionally, benzo-1,5-enynal vinyl carbene, reacted variety alkenes [2 + 1] cycloaddition, [4 3] formal allylation, spiro fused polycyclic heterocycles. Coupling desymmetrization, successfully diynals, constructing furan-fused dihydropiperidines alkyne-substituted aza-quaternary stereocenter. Notably, analyzing X-ray structures several dirhodium-alkyne π-complexes, together results DFT calculations control experiments, obtained evidence supporting making well-defined paddlewheel-like dirhodium(II) stand out among complexes. We anticipate that our research will significantly advance fields dirhodium, alkyne, chemistry.

Language: Английский

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Exploiting Remarkable Reactivities of Ynamides: Opportunities in Designing Catalytic Enantioselective Reactions

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(23), P. 13978 - 13992

Published: Nov. 17, 2020

Ynamides consisting of an electron-withdrawing group on the nitrogen atom have proven to be powerful and versatile building blocks that are involved in a variety useful chemical transformations. Nonetheless, their utilization asymmetric catalysis is still its infancy has only recently attracted attention synthetic organic community. The focus this review present overview exciting results achieved thus far field catalytic reactions ynamides with emphasis advantages, limitations, mechanisms, applications associated current approaches. In addition, personal outlook challenges limitations need overcome area also given at end.

Language: Английский

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Synthesis of axially chiral compounds through catalytic asymmetric reactions of alkynes

Chem Catalysis, Journal Year: 2021, Volume and Issue: 1(7), P. 1378 - 1412

Published: Oct. 22, 2021

Language: Английский

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Brønsted Acid Catalyzed Dearomatization by Intramolecular Hydroalkoxylation/Claisen Rearrangement: Diastereo‐ and Enantioselective Synthesis of Spirolactams

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(52), P. 27164 - 27170

Published: Oct. 21, 2021

Described herein is a novel Brønsted acid catalyzed intramolecular hydroalkoxylation/Claisen rearrangement, allowing the practical and atom-economic synthesis of range valuable spirolactams from readily available ynamides in generally good to excellent yields with diastereoselectivities broad substrate scope. Importantly, an unexpected dearomatization nonactivated arenes heteroaromatic compounds involved this tandem sequence. Moreover, asymmetric version cyclization was also achieved by efficient kinetic resolution chiral phosphoric catalysis. In addition, [3,3]-rearrangement shown be kinetically preferred over related [1,3]-rearrangement theoretical calculations.

Language: Английский

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Copper‐Catalyzed Asymmetric Diyne Cyclization via [1,2]‐Stevens‐Type Rearrangement for the Synthesis of Chiral Chromeno[3,4‐c]pyrroles

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(7)

Published: Dec. 14, 2021

Here, we report a copper-catalyzed asymmetric cascade cyclization/[1,2]-Stevens-type rearrangement via non-diazo approach, leading to the practical and atom-economic assembly of various valuable chiral chromeno[3,4-c]pyrroles bearing quaternary carbon stereocenter in generally moderate good yields with wide substrate scope excellent enantioselectivities (up 99 % ee). Importantly, this protocol not only represents first example catalytic [1,2]-Stevens-type based on alkynes but also constitutes formal carbene insertion into Si-O bond.

Language: Английский

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Recent advances towards organocatalytic enantioselective desymmetrizing reactions

Trends in Chemistry, Journal Year: 2022, Volume and Issue: 4(3), P. 191 - 205

Published: Jan. 22, 2022

Language: Английский

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