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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Diverse Approaches for Enantioselective C−H Functionalization Reactions Using Group 9 Cp^xM^III Catalysts

Chemistry - A European Journal, Journal Year: 2020, Volume and Issue: 26(33), P. 7346 - 7357

Published: Jan. 29, 2020

Transition-metal-catalyzed C-H functionalization reactions with Cp*MIII catalysts (M=Co, Rh, Ir) have found a wide variety of applications in organic synthesis. Albeit the intrinsic difficulties achieving catalytic stereocontrol using these due to their lack additional coordination sites for external chiral ligands and conformational flexibility Cp ligand, enantioselective Group 9 metal triad Cp-type been intensively studied since 2012. In this minireview, progress according type catalyst used are summarized discussed. The development Cpx complexes thereof, artificial metalloenzymes, carboxylate-assisted activations, alkylations assisted by carboxylic acids or sulfonates, transient directing groups

Language: Английский

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Chiral Carboxylic Acid Assisted Enantioselective C–H Activation with Achiral Cp^xM^III (M = Co, Rh, Ir) Catalysts

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(11), P. 6455 - 6466

Published: May 17, 2021

Enantioselective C–H functionalization is a powerful tool for synthesizing chiral molecules. In the past few years, combination of high-valent group 9 metals with achiral Cpx ligands and carboxylic acids (CCA) has emerged as promising catalytic system to enable selective cleavage enantiotopic bonds. This Perspective summarizes background, catalyst design, applied reactions in detail, followed by discussion future directions.

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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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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Recent Advances in Asymmetric Organometallic Electrochemical Synthesis (AOES)

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

Published: Jan. 19, 2025

ConspectusIn recent years, our research group has dedicated significant effort to the field of asymmetric organometallic electrochemical synthesis (AOES), which integrates electrochemistry with transition metal catalysis. On one hand, we have rationalized that compounds can serve as molecular electrocatalysts (mediators) reduce overpotentials and enhance both reactivity selectivity reactions. other conditions for catalysis be substantially improved through electrochemistry, enabling precise modulation metal's oxidation state by controlling potentials regulating electron transfer rate via current adjustments. This synergistic approach addresses key challenges inherent in traditional catalysis, particularly those related use redox-active chemical reagents. Furthermore, redox conveniently tuned modifying their ligands, thereby governing reaction regioselectivity stereoselectivity. As a result, AOES emerged powerful promising tool chiral compounds.In this Account, summarize contextualize efforts AOES. Our primary strategy involves leveraging controllability potential regulate organometallics, facilitating desired An efficient platform was established under mild conditions, significantly reducing reliance on been systematically categorized into three sections based distinct electrolysis modes: combined anodic oxidation, cathodic reduction, paired electrolysis. In each section, highlight innovative discoveries tailored unique characteristics respective modes.In many transformations, metal-catalyzed reactions involving reagents utilizing exhibit similar reactivities. However, also observed notable differences certain cases. These findings include following: (1) Enhanced efficiency synthesis: instance, Rh-catalyzed enantioselective functionalization C–H bonds demonstrates superior efficiency. (2) Expanded scope transformations: previously challenging achieved due tunability potentials. A example is reductive coupling aryl chlorides, expands range accessible transformations. Additionally, mechanistic studies explore techniques intrinsic such controlled experiments, impact electrode materials catalyst performance, cyclic voltammetry studies. investigations provide more intuitive understanding behavior catalysts study mechanisms, guide design new catalytic systems.The advancements offer robust environmentally friendly sustainable selective By integrating developed versatile organic not only enhances but reduces environmental impact. We anticipate Account will stimulate further innovation realm AOES, leading discovery systems development synthetic methodologies.

Language: Английский

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Absolute Configurations of Synthetic Molecular Scaffolds from Vibrational CD Spectroscopy

The Journal of Organic Chemistry, Journal Year: 2019, Volume and Issue: 84(14), P. 8797 - 8814

Published: May 2, 2019

Vibrational circular dichroism (VCD) spectroscopy is one of the most powerful techniques for determination absolute configurations (AC), as it does not require any specific UV/vis chromophores, no chemical derivatization, and growth suitable crystals. In past decade, has become increasingly recognized by chemists from various fields synthetic chemistry such total synthesis drug discovery well developers asymmetric catalysts. This perspective article gives an overview about important experimental aspects a VCD-based AC explains theoretical analysis. The comparison computational spectra that leads to final conclusion target molecules described. addition, review summarizes unique VCD studies carried out in period 2008–2018 focus on unknown ACs new compounds, which were obtained its enantiopure form either through direct or chiral chromatography.

Language: Английский

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Rhodium(III)‐Catalyzed Atroposelective Synthesis of Biaryls by C−H Activation and Intermolecular Coupling with Sterically Hindered Alkynes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(32), P. 13288 - 13294

Published: April 16, 2020

Abstract Reported herein is the atroposelective synthesis of biaryl NH isoquinolones by Rh III ‐catalyzed C−H activation benzamides and intermolecular [4+2] annulation for a broad scope 2‐substituted 1‐alkynylnaphthalenes, as well sterically hindered, symmetric diarylacetylenes. The axial chirality constructed based on dynamic kinetic transformation alkyne in redox‐neutral with benzamides, insertion being stereodetermining. reaction accommodates both heteroaryl carboxamides proceeds excellent regioselectivity (if applicable) enantioselectivities (average 91.8 % ee ). An enantiomerically diastereomerically pure rhodacyclic complex was prepared offers insight into enantiomeric control coupling system, wherein steric interactions between amide directing group substrate dictate regio‐ enantioselectivity.

Language: Английский

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Chiral Transient Directing Groups in Transition-Metal-Catalyzed Enantioselective C–H Bond Functionalization

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(21), P. 12898 - 12919

Published: Oct. 21, 2020

Transition-metal-catalyzed C–H bond functionalization has known a rapid evolution in the last years, offering modern strategies for reaching high molecular complexity step- and atom-economical way. Despite indisputable advances, selectivity issues still remain, given ubiquity of bonds on molecules; thus, several approaches have been developed to tackle this challenge. Among them, use transient directing group emerged as an effective tool, circumventing need extra synthetic steps install then cleave molecule. More recently, strategy successfully applied even more challenging transition-metal-catalyzed enantioselective functionalization. This review will highlight discuss main advances made chiral C(sp2)–H C(sp3)–H by transition-metal catalysis.

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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