Recent Advances in Metal‐Catalyzed Functionalization of Indoles

Advanced Synthesis & Catalysis, Journal Year: 2021, Volume and Issue: 363(11), P. 2723 - 2739

Published: April 7, 2021

Abstract Indole is one of the most important heterocycles in organic synthesis, natural products, and drug discovery. Recently, tremendous advances selective functionalization indoles have been reported. Although powered by transition metal catalysis, exceedingly useful methods absence metals also In this review, we provide an overview reactions that published last years with a focus on recent advances, aims, future trends. The review organized positional selectivity type used for functionalization. particular, discuss major transition‐metal‐catalyzed C−H at classical C2/C3 positions, remote C4/C7 cross‐coupling, transition‐metal‐free magnified image

Language: Английский

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Ligand‐Enabled Palladium(II)‐Catalyzed Enantioselective β‐C(sp³)−H Arylation of Aliphatic Tertiary Amides**

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(17)

Published: March 5, 2023

Amide is one of the most widespread functional groups in organic and bioorganic chemistry, it would be valuable to achieve stereoselective C(sp3 )-H functionalization amide molecules. Palladium(II) catalysis has been prevalently used C-H activation chemistry past decades, however, due weakly-coordinating feature simple amides, challenging their direct with enantiocontrol by PdII catalysis. Our group developed sulfoxide-2-hydroxypridine (SOHP) ligands, which exhibited remarkable activity Pd-catalyzed C(sp2 activation. In this work, we demonstrate that chiral SOHP ligands served as an ideal solution enantioselective amides. Herein, report efficient asymmetric /SOHP-catalyzed β-C(sp3 arylation aliphatic tertiary ligand plays a key role deprotonation-metalation step.

Language: Английский

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Transition-Metal-Catalyzed Divergent C–H Functionalization of Five-Membered Heteroarenes

Accounts of Chemical Research, Journal Year: 2021, Volume and Issue: 54(24), P. 4518 - 4529

Published: Dec. 10, 2021

Conversion of common reactants to diverse products is a key objective organic syntheses. Recent developments in transition-metal-catalyzed C-H functionalization have increased the interest such conversions. Both position and type substituent can be varied, allowing systematic diversification structural cores. Because five-membered heteroarenes (pyrazole, imidazole, thiazole, pyrrole, thiophene) are ubiquitous pharmaceuticals functional materials, selective these heterocyclic cores facilitates both optimization their physicochemical properties streamlining preparation. In addition, parent forms heterocycles more readily available inexpensive than any other derivatives families. Hence, nondirected highly desirable. Although various regioselective reactions been developed, many them target most reactive site; hence, except for some extensively studied arylation reactions, regiodivergent two or sites has limited.This Account summarizes our work on regiodivergent, with alkenes alkynes. These unsaturated hydrocarbons available, all composing atoms incorporated into high atom efficiency. Furthermore, installed alkenyl groups transformed useful groups. To achieve comparable selectivity that observed traditional electrophilic reagents strong bases, transition metal catalytic system was carefully devised streamlined synthesis. A judicious choice metals, ligands, acid base additives, solvents orchestrates divergent transformations using electronic steric effects heteroarenes. cleavage rate- site-selectivity-determining step cases, subsequent steps involving formation C-C bonds often critical steps. For step, modulating catalysts make allows preferential alkenylation at nucleophilic position. presence an internal exploited concerted metalation-deprotonation acidic bond offers alternative regioselectivity. we developed own ligand based conformationally rigid pyrazolonaphthyridine scaffold enables aerobic control. We showed further extended chemodivergent norbornene derivatives. Depending whether palladacycle formed, selectively undergo 1:2 annulation three-component azoles through Pd-norbornene adducts Catellani 2:1 intermediates.Other research also contributed development investigations ranging from pioneering studies early days recent new ligands. discussed context. approaches provide access systematically varied substituents. believe systems mechanistic insights gained will enrich fields beyond

Language: Английский

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Nondirected Pd-Catalyzed C–H Perdeuteration and meta-Selective Alkenylation of Arenes Enabled by Pyrazolopyridone Ligands

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(7), P. 4042 - 4052

Published: March 16, 2023

The development of ligands and the elucidation their roles in catalytic cycle are key to achieving high efficiency selectivity nondirected transition-metal-catalyzed C–H functionalization. In particular, careful ligand design can enable functionalization previously inaccessible substrate positions, which lead regiodivergent transformations common reactants. this study, a series pyrazolopyridone (PzPyOH) that be easily prepared single step was developed for Pd-catalyzed perdeuteration meta-selective alkenylation arenes. system, 2-pyridone moiety incorporated function as an internal base, facilitating cleavage rendering activation reversible, even at challenging sp2 bonds, thus enabling perdeuteration. addition, reversible bonds implies site is determined during migratory insertion reaction, thereby preferentially functionalizing meta-positions rather than typically more reactive ortho- para-positions anisole derivatives. Further, electronic structural properties pyrazole provide flexibility binding Pd, facile coordination alkene coupling partner alkenylation. process, hydrogen bonding between pyridone acetate crucial stabilize intermediates, allowing different types modes, including L,L- L,X-type bidentate monodentate binding. Kinetic computational studies support proposed mechanisms alkenylation, findings reveal factors functionalization, will useful further pyrazole- pyridone-containing transition metal catalysis.

Language: Английский

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Weak Chelation-Assisted C4-Selective Alkylation of Indoles with Cyclopropanols via Sequential C–H/C–C Bond Activation

Organic Letters, Journal Year: 2022, Volume and Issue: 24(32), P. 6000 - 6005

Published: Aug. 10, 2022

A Rh-catalyzed weak chelation-guided C4-alkylation of indoles has been accomplished using cyclopropanols as an alkylating agent via the cascade C–H and C–C bond activation. The substrate scope, functional group tolerance, late-stage mutation drug molecules are important practical features.

Language: Английский

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Extended π-conjugated systems by external ligand-assisted C−H olefination of heterocycles: Facile access to single-molecular white-light-emitting and NIR fluorescence materials

Chinese Chemical Letters, Journal Year: 2024, Volume and Issue: unknown, P. 110113 - 110113

Published: June 1, 2024

Language: Английский

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Chiral Ligands for Palladium-Catalyzed Coordination-Assisted Enantioselective C(sp³)—H Functionalization Reactions

Chinese Journal of Organic Chemistry, Journal Year: 2025, Volume and Issue: 45(2), P. 602 - 602

Published: Jan. 1, 2025

Language: Английский

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Ligand-Enabled Palladium(II)-Catalyzed γ-C(sp³)–H Arylation of Primary Aliphatic Amines

Organic Letters, Journal Year: 2023, Volume and Issue: 26(1), P. 29 - 34

Published: Dec. 21, 2023

The Pd(II)/sulfoxide-2-hydroxypyridine catalytic system shows promising activity in C–H activation chemistry. In this study, we showcase how solves the problem of native primary amine-directed γ-C(sp3)–H arylation. Primary amines with different complexities are compatible established methodology, and range applicable substrates can be expanded to include pyridine, oxime ether, pyridine N-oxide.

Language: Английский

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Sterically controlled C–H alkenylation of pyrroles and thiophenes

Chemical Communications, Journal Year: 2021, Volume and Issue: 57(89), P. 11791 - 11794

Published: Jan. 1, 2021

Pd-catalyzed C-H alkenylations targeting the least hindered position of N-alkyl pyrroles and 3-substituted thiophenes, as opposed to electronically controlled approaches, are developed. The steric demand stable bidentate binding mode pyrazolonaphthyridine ligand key success these sterically using oxygen an oxidant.

Language: Английский

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Unveiling the Mechanistic Role of Chiral Palladacycles in Pd(II)‐Catalyzed Enantioselective C(sp³)−H Functionalization

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(29)

Published: May 7, 2024

Palladium-catalyzed enantioselective C(sp

Language: Английский

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