Chiral Cyclopentadienyl Ligands: Design, Syntheses, and Applications in Asymmetric Catalysis

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(24), P. 13198 - 13224

Published: July 16, 2020

The creation of new chiral ligands capable providing high stereocontrol in metal-catalyzed reactions is crucial modern organic synthesis. production bioactive molecules as single enantiomers increasingly required, and asymmetric catalysis with metal complexes constitutes one the most efficient synthetic strategies to access optically active compounds. Herein we offer a historical overview on development derivatives ubiquitous cyclopentadienyl ligand (CpX ), detail their successful application broad range transformations. Those include functionalization challenging C-H bonds beyond, giving an extensive catalogue valuable molecules. A critical comparison existing families, design, synthesis, complexation different metals also provided. In addition, future research directions are discussed further enhance performance CpX enantioselective catalysis.

Language: Английский

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Transition Metal Catalyzed Enantioselective C(sp²)–H Bond Functionalization

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(23), P. 13748 - 13793

Published: Nov. 12, 2020

Direct catalytic transformation of C–H bonds to new functionalities has provided a powerful strategy synthesize complex molecular scaffolds in straightforward way. Unstinting efforts the synthetic community have helped overcome long-standing major challenge regioselectivity by introducing directing group concept. However, full potential cannot be realized unless activated are stereochemically controlled. The enantioselective bond functionalization could provide an imperative tool for sustainable way synthesizing chiral scaffolds. Despite intrinsic challenges achieving stereocontrol, developed different tools order achieve stereoselective functionalization. In this review, we discuss remarkable recent advances emerging area C(sp2)–H highlight and opportunities, emphasizing techniques so far.

Language: Английский

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Rhodium-Catalyzed Asymmetric C–H Functionalization Reactions

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(16), P. 10079 - 10134

Published: Aug. 1, 2023

This review summarizes the advancements in rhodium-catalyzed asymmetric C–H functionalization reactions during last two decades. Parallel to rapidly developed palladium catalysis, rhodium catalysis has attracted extensive attention because of its unique reactivity and selectivity reactions. In recent years, Rh-catalyzed have been significantly many respects, including catalyst design, reaction development, mechanistic investigation, application synthesis complex functional molecules. presents an explicit outline catalysts ligands, mechanism, scope coupling reagents, applications.

Language: Английский

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Oxygen‐Linked Cyclopentadienyl Rhodium(III) Complexes‐Catalyzed Asymmetric C−H Arylation of Benzo[h]quinolines with 1‐Diazonaphthoquinones

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(28), P. 15510 - 15516

Published: April 16, 2021

Abstract Chiral cyclopentadienyl rhodium (CpRh) complex‐catalyzed asymmetric C−H functionalization reactions have witnessed a significant progress in organic synthesis. In sharp contrast, the reported chiral Cp ligands are limited to C‐linked and often synthetically challenging. To address these issues, we developed novel class of tunable bearing oxygen linkers, which were efficient catalysts for arylation benzo[ h ]quinolines with 1‐diazonaphthoquinones, affording axially heterobiaryls excellent yields enantioselectivity (up 99 % yield, 98.5:1.5 er). Mechanistic studies suggest that reaction is likely proceed by electrophilic activation, followed coupling cyclometalated rhodium(III) complex 1‐diazonaphthoquinones.

Language: Английский

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Cobalt-Catalyzed Enantioselective C–H Arylation of Indoles

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(2), P. 798 - 806

Published: Jan. 10, 2022

Atropoisomeric (hetero)biaryls are scaffolds with increasing importance in the pharmaceutical and agrochemical industries. Although it is most obvious disconnection to construct such compounds, direct enantioselective C–H arylation through concomitant induction of chiral information remains extremely challenging uncommon. Herein, unprecedented earth-abundant 3d-metal-catalyzed atroposelective reported, furnishing rare atropoisomeric C2-arylated indoles. Kinetic studies DFT computation revealed an uncommon mechanism for this asymmetric transformation, oxidative addition being rate- enantio-determining step. Excellent stereoselectivities were reached (up 96% ee), while using unusual N-heterocyclic carbene ligand bearing essential remote substituent. Attractive dispersion interactions along positive C–H---π exerted by identified as key factors guarantee excellent enantioselection.

Language: Английский

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Electrooxidative palladium- and enantioselective rhodium-catalyzed [3 + 2] spiroannulations

Chemical Science, Journal Year: 2022, Volume and Issue: 13(9), P. 2783 - 2788

Published: Jan. 1, 2022

Despite indisputable progress in the development of electrochemical transformations, electrocatalytic annulations for synthesis biologically relevant three-dimensional spirocyclic compounds has as yet not been accomplished. In sharp contrast, herein, we describe palladaelectro-catalyzed C-H activation/[3 + 2] spiroannulation alkynes by 1-aryl-2-naphthols. Likewise, a cationic rhodium(iii) catalyst was shown to enable electrooxidative [3 spiroannulations via formal C(sp3)-H activations. The versatile featured broad substrate scope, employing electricity green oxidant lieu stoichiometric chemical oxidants under mild conditions. An array enones and diverse spiropyrazolones, bearing all-carbon quaternary stereogenic centers were thereby accessed user-friendly undivided cell setup, with molecular hydrogen sole byproduct.

Language: Английский

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Rhodium‐Catalyzed Atroposelective Construction of Indoles via C−H Bond Activation

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 60(15), P. 8391 - 8395

Published: Dec. 18, 2020

Reported herein is the rhodium(III)-catalyzed C-H activation of anilines bearing an N-isoquinolyl directing group for oxidative [3+2] annulation with four classes internal alkynes, leading to atroposelective indole synthesis via dynamic kinetic C-N reductive elimination constituting stereo-determining step. This reaction proceeds under mild conditions high regio- and enantioselectivity functional compatibility.

Language: Английский

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Rhodium‐Catalyzed C−H Activation‐Based Construction of Axially and Centrally Chiral Indenes through Two Discrete Insertions

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(30), P. 16628 - 16633

Published: May 19, 2021

Abstract Reported herein is asymmetric [3+2] annulation of arylnitrones with different classes alkynes catalyzed by chiral rhodium(III) complexes, the nitrone acting as an electrophilic directing group. Three indenes/indenones have been effectively constructed, depending on nature substrates. The coupling system features mild reaction conditions, excellent enantioselectivity, and high atom‐economy. In particular, N ‐benzylnitrones sterically hindered afforded C−C or C−N atropochiral pentatomic biaryls a C‐centered point‐chirality in enantio‐ diastereoselectivity (45 examples, average 95.6 % ee ). These center axis are disposed distal fashion they constructed via two distinct migratory insertions that stereo‐determining under catalyst control.

Language: Английский

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Applications of Chiral Cyclopentadienyl (Cp^x) Metal Complexes in Asymmetric Catalysis

European Journal of Organic Chemistry, Journal Year: 2020, Volume and Issue: 2020(42), P. 6512 - 6524

Published: July 21, 2020

Metal complexes containing cyclopentadienyl (Cp) ligands are versatile and robust catalysts widely applied in organic synthesis. During the last two decades chiral Cp x have been a variety of enantioselective transformations. Often associated with Group 9 metals (Co, Rh, Ir), also used combination early transition‐metals rare‐earth elements. In this minireview asymmetric reactions that successfully steered ligand metal discussed according to coordinated. Several designs diverse array reactions, particular C–H functionalisation, binaphthyl‐derived leading field. Challenges these derive from need for their multi‐step synthesis, recently new were designed, which can be accessed shorter sequences readily available starting materials.

Language: Английский

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Binaphthyl Scaffold: A Class of Versatile Structure in Asymmetric C–H Functionalization

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(15), P. 9359 - 9396

Published: July 18, 2022

Over the past decades, transition metal-catalyzed enantioselective C–H functionalization has emerged as a straightforward and powerful tool for rapid access to chiral molecules. The enormous advances achieved in this emerging area largely rely on development of ligands that can enable both high levels enantiocontrol efficiency. Chiral bearing binaphthyl scaffolds have been proven be versatile asymmetric due their availability, unique stereochemical features, ease fine-tuning steric electronic properties. In Review, we summarized advance applications basis scaffold functionalization.

Language: Английский

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