Transition Metal-Catalyzed Tandem Reactions of Ynamides for Divergent N-Heterocycle Synthesis

Accounts of Chemical Research, Journal Year: 2020, Volume and Issue: 53(9), P. 2003 - 2019

Published: Sept. 1, 2020

ConspectusYnamides are electron-rich heteroatom-substituted alkynes with a C-C triple bond directly attached to the amide group. Importantly, this group is able impose an electronic bias, thus resulting in highly regioselective attack of polarized alkyne by large variety nucleophiles. Over past two decades, catalytic reactions ynamides have experienced dramatic developments, especially those catalyzed transition metals. As result, been widely applied rapid and efficient assembly versatile structurally complex N-containing molecules, atom-economic stereoselective way.On basis newly developed ynamide preparations new transformations, we first oxidation-initiated tandem such as zinc-catalyzed oxidation/C-H functionalization copper-catalyzed oxidation/carbene metathesis, leading divergent synthesis isoquinolones, β-carbolines, pyrrolo[3,4-c]quinolin-1-ones. protocol represents non-noble-metal-catalyzed intermolecular oxidation N-oxide type oxidants, related overoxidation could be dramatically inhibited non-noble-metal catalysis. Then, achieved gold-catalyzed amination-initiated via α-imino gold carbenes for construction various 2-aminoindoles, 3-amino-β-carbolines, 2-aminopyrroles, where types nitrene transfer reagents (benzyl azides isoxazoles) were discovered. In particular, use isoxazoles generation metal has also elegantly exploited Hashmi, Liu, many other groups, providing ready access wide range functionalized N-heterocycles. Moreover, revealed that donor/donor copper generated diyne cyclization under mild conditions. These novel undergo asymmetric C-H insertion, cyclopropanation, formal [3 + 2] cycloaddition produce diverse chiral polycyclic pyrroles good excellent enantioselectivities. Thus, strategy may open avenues reaction ynamides, which remain largely unexplored deserve more attention. Meanwhile, accomplished practical medium-sized lactams yttrium-catalyzed cascade allyl alcohol-tethered combination radical chemistry based on visible-light photoredox catalysis useful 2-benzhydrylindoles 3-benzhydrylisoquinolines.In Account, describe panoramic picture our recent contributions since 2015 development application organic metal-catalyzed focusing tetrafunctionalization ynamides. studies provide not only attractive methods valuable N-heterocycles but some insights into exploration carbene chemistry.

Language: Английский

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Brønsted acid-mediated reactions of ynamides

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(24), P. 8897 - 8909

Published: Jan. 1, 2020

This review summarizes the latest trends and developments of Brønsted acid-mediated reactions ynamides, including cycloaddition, cyclization so on.

Language: Английский

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Asymmetric synthesis with ynamides: unique reaction control, chemical diversity and applications

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(23), P. 8543 - 8583

Published: Jan. 1, 2020

The diversity, utility and mechanistic aspects of asymmetric synthesis with ynamides developed during the last decade is discussed.

Language: Английский

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Ynamide Smiles Rearrangement Triggered by Visible-Light-Mediated Regioselective Ketyl–Ynamide Coupling: Rapid Access to Functionalized Indoles and Isoquinolines

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(7), P. 3636 - 3644

Published: Jan. 31, 2020

In the past decades, significant advances have been made on radical Smiles rearrangement. However, eventually formed intermediates in these reactions are limited to amidyl radical, except for few examples initiated by a N-centered radical. Here, novel and practical rearrangement triggered photoredox-catalyzed regioselective ketyl-ynamide coupling is reported, which represents first of ynamides. This method enables facile access variety valuable 2-benzhydrylindoles with broad substrate scope generally good yields under mild reaction conditions. addition, this chemistry can also be extended divergent synthesis versatile 3-benzhydrylisoquinolines through similar rearrangement, followed dehydrogenative oxidation. Moreover, such an ynamide intermolecular photoredox catalysis via addition external sources achieved. By control experiments, was shown proceed key ketyl α-imino carbon intermediates.

Language: Английский

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Reactivity of ynamides in catalytic intermolecular annulations

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 50(4), P. 2582 - 2625

Published: Dec. 24, 2020

This review comprehensively summarizes the advances achieved in catalytic intermolecular annulations of ynamides from 2010 to 2020.

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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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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Copper-Catalyzed Asymmetric Reaction of Alkenyl Diynes with Styrenes by Formal [3 + 2] Cycloaddition via Cu-Containing All-Carbon 1,3-Dipoles: Access to Chiral Pyrrole-Fused Bridged [2.2.1] Skeletons

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(16), P. 7618 - 7626

Published: April 2, 2020

The generation of metal-containing 1,3-dipoles from metal carbenes represents a significant advance in 1,3-dipolar cycloaddition reactions. However, these transformations have so far been limited to reactions based on diazo compounds or triazoles as precursors. Herein, we disclose copper-catalyzed enantioselective reaction alkenyl N-propargyl ynamides with styrene derivatives by formal [3 + 2] via Cu-containing all-carbon 1,3-dipoles, which constitutes novel way for the carbenes. This protocol allows practical and atom-economical synthesis valuable chiral pyrrole-fused bridged [2.2.1] skeletons moderate good yields (up 90% yield) excellent diastereoselectivities (dr > 50/1) generally enantioselectivities >99% ee).

Language: Английский

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Copper‐Catalyzed Azide–Ynamide Cyclization to Generate α‐Imino Copper Carbenes: Divergent and Enantioselective Access to Polycyclic N‐Heterocycles

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(41), P. 17984 - 17990

Published: July 4, 2020

Here an efficient copper-catalyzed cascade cyclization of azide-ynamides via α-imino copper carbene intermediates is reported, representing the first generation carbenes from alkynes. This protocol enables practical and divergent synthesis array polycyclic N-heterocycles in generally good to excellent yields with broad substrate scope diastereoselectivities. Moreover, asymmetric azide-ynamide has been achieved high enantioselectivities (up 98:2 e.r.) by employing BOX-Cu complexes as chiral catalysts. Thus, this constitutes example azide-alkyne cyclization. The proposed mechanistic rationale for further supported theoretical calculations.

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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