Iridium-Catalyzed Asymmetric Allylic Substitution Reactions

Chemical Reviews, Journal Year: 2018, Volume and Issue: 119(3), P. 1855 - 1969

Published: Dec. 24, 2018

In this review, we summarize the origin and advancements of iridium-catalyzed asymmetric allylic substitution reactions during past two decades. Since first report in 1997, Ir-catalyzed have attracted intense attention due to their exceptionally high regio- enantioselectivities. been significantly developed recent years many respects, including ligand development, mechanistic understanding, substrate scope, application synthesis complex functional molecules. an explicit outline ligands, mechanism, scope nucleophiles, applications is presented.

Language: Английский

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Synergistic Dual Transition Metal Catalysis

Chemical Reviews, Journal Year: 2020, Volume and Issue: 120(24), P. 13382 - 13433

Published: Nov. 29, 2020

Synergistic catalysis, a type of plural catalysis which utilizes at least two different catalysts to enable reaction between separately activated substrates, has unlocked plethora previously unattainable transformations and novel chemical reactivity. Despite the appreciable utility synergistic specific examples involving transition metals have been limited, as ensuring judicious choice parameters prevent deactivation catalysts, undesirable monocatalytic event(s) leading side products, or premature termination other potentially troublesome outcomes present formidable challenge. Excluding those driven by photocatalytic mechanisms, this review will highlight reported reactions that make use simultaneous catalytic cycles metal catalysts.

Language: Английский

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Stereodivergent Allylic Substitutions with Aryl Acetic Acid Esters by Synergistic Iridium and Lewis Base Catalysis

Journal of the American Chemical Society, Journal Year: 2016, Volume and Issue: 139(1), P. 87 - 90

Published: Dec. 17, 2016

The preparation of all possible stereoisomers a given chiral molecule bearing multiple stereocenters by simple and unified method is significant challenge in asymmetric catalysis. We report stereodivergent allylic substitutions with aryl acetic acid esters catalyzed synergistically metallacyclic iridium complex benzotetramisole. Through permutations the enantiomers two catalysts, four products adjacent are accessible high diastereoselectivity enantioselectivity. resulting activated ester can be converted readily to enantioenriched amides, unactivated esters, carboxylic acids one-pot manner.

Language: Английский

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Stereoselective and Site-Specific Allylic Alkylation of Amino Acids and Small Peptides via a Pd/Cu Dual Catalysis

Journal of the American Chemical Society, Journal Year: 2017, Volume and Issue: 139(29), P. 9819 - 9822

Published: July 7, 2017

We report a stereoselective and site-specific allylic alkylation of Schiff base activated amino acids small peptides via Pd/Cu dual catalysis. A range noncoded α,α-dialkyl α-amino were easily synthesized in high yields with excellent enantioselectivities (up to >99% ee). Furthermore, direct highly synthesis enantiopure α-alkyl or residues incorporated at specific sites was accomplished using this catalyst system.

Language: Английский

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Asymmetric [4+2] Annulation of C1 Ammonium Enolates with Copper‐Allenylidenes

Angewandte Chemie International Edition, Journal Year: 2017, Volume and Issue: 56(19), P. 5212 - 5216

Published: March 31, 2017

Abstract An asymmetric catalytic decarboxylative [4+2] annulation of 4‐ethynyl dihydrobenzooxazinones and carboxylic acids has been established by cooperative copper nucleophilic Lewis base catalysis. A C1 ammonium enolate copper–allenylidene complex, each catalytically generated from different substrates, underwent a cascade propargylation lactamization process to yield optically active 3,4‐dihydroquinolin‐2‐one derivatives with excellent levels stereoselectivity (up 99 % ee , 95:5 d.r.).

Language: Английский

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Cooperative bimetallic catalysis in asymmetric allylic substitution

Organic & Biomolecular Chemistry, Journal Year: 2017, Volume and Issue: 15(46), P. 9747 - 9759

Published: Jan. 1, 2017

Synergistic catalysis is gaining increasing attention due to its advantages over traditional catalytic methodologies, such as improved activity, broader substrate scope, increased selectivity and lower cost. Methodologies involving the synergistic combination of metal catalysts organocatalysts have been intensively studied. Given clear benefits bimetallic catalyst systems consisting two distinct catalysts, cooperative has proved be successful for a number difficult asymmetric transformations. This review highlights recent advances in allylic substitution reactions. Strategies using chiral effect second achiral transformations are discussed. Additionally, several challenging reactions realized by employing different manner also covered.

Language: Английский

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Organo/Transition-Metal Combined Catalysis Rejuvenates Both in Asymmetric Synthesis

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(6), P. 2415 - 2437

Published: Jan. 20, 2022

Since its advent two decades ago, asymmetric organo/transition-metal combined catalysis (AOMC), including cooperative and relay catalysis, has leveraged redistribution of chemical bonds to build up molecular complexity enantio-differentiation form individual enantiomers with activations from versatile organocatalysts transition-metal complexes. The goal this perspective is provide readers the fundamental attributes AOMC─orthogonality, kinetics, mechanism, selectivity─to understand how an organocatalyst a complex would collaborate enable fruitful new reaction development what are intrinsic pathways unproductive events, such as catalyst self-quenching. In closing, future opportunities AOMC have been directed toward prediction effective combination, introducing enzyme focus on transient radical intermediate, animate area in years come.

Language: Английский

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Recent Developments and Trends in Asymmetric Organocatalysis

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 26(1)

Published: Oct. 17, 2022

Asymmetric organocatalysis has experienced a long and spectacular way since the early reports over century ago by von Liebig, Knoevenagel Bredig, showing that small (chiral) organic molecules can catalyze (asymmetric) reactions. This was followed impressive first highly enantioselective in second half of last century, until hype initiated 2000 milestone publications MacMillan List, which finally culminated 2021 Nobel Prize Chemistry. short Perspective aims at providing brief introduction to field looking on historical development more classical methods concepts, discussing selected advanced recent examples opened new directions diversity within this still growing field.

Language: Английский

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Synergizing palladium with Lewis base catalysis for stereodivergent coupling of 1,3-dienes with pentafluorophenyl acetates

Chem, Journal Year: 2022, Volume and Issue: 8(10), P. 2784 - 2796

Published: Aug. 17, 2022

Language: Английский

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Synergistic Cu/Pd Catalysis for Enantioselective Allylic Alkylation of Aldimine Esters: Access to α,α‐Disubstituted α‐Amino Acids

Angewandte Chemie International Edition, Journal Year: 2017, Volume and Issue: 56(40), P. 12312 - 12316

Published: July 25, 2017

Abstract An unprecedented enantioselective allylic alkylation of readily available aldimine esters has been developed, and is catalyzed by a synergistic Cu/Pd catalyst system. This strategy provides facile access to nonproteinogenic α,α‐disubstituted α‐amino acids in high yield with excellent enantioselectivity. The more challenging double glycinate‐derived imine was also realized. Furthermore, this methodology applied for the construction key intermediate PLG peptidomimetics.

Language: Английский

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