Bimetallic Catalysis in Stereodivergent Synthesis

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(45)

Опубликована: Авг. 2, 2022

Abstract Bimetallic catalysis has emerged as an efficient strategy for the development of new chemical reactions. Importantly, this also provides a simple and powerful platform stereodivergent synthesis, whereby all possible stereoisomers products bearing two stereocenters can be easily prepared from same set starting materials. In Minireview, allylic substitution, propargylic hydrofunctionalization, annulation based on bimetallic been summarized. It is expected that more catalytic systems will developed applied synthesis valuable molecules.

Язык: Английский

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Enantio‐ and Diastereodivergent Synthesis of Spirocycles through Dual‐Metal‐Catalyzed [3+2] Annulation of 2‐Vinyloxiranes with Nucleophilic Dipoles

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(47), С. 24941 - 24949

Опубликована: Сен. 17, 2021

The development of efficient and straightforward methods for obtaining all optically active isomers structurally rigid spirocycles from readily available starting materials is great value in drug discovery chiral ligand development. However, the stereodivergent synthesis bearing multiple stereocenters remains an unsolved challenge owing to steric hindrance ring strain. Herein, we report enantio- diastereodivergent through dual-metal-catalyzed [3+2] annulation oxy π-allyl metallic dipoles with less commonly employed nucleophilic (imino esters). A series spiro compounds a pyrroline olefin were easily synthesized manner (up 19:1 dr, >99 % ee), which showed promise as new type N-olefin ligand. Preliminary mechanistic studies also carried out understand process this bimetallic catalysis.

Язык: Английский

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Stereodivergent Synthesis of Enantioenriched γ‐Butyrolactones Bearing Two Vicinal Stereocenters Enabled by Synergistic Copper and Iridium Catalysis

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(47), С. 24930 - 24940

Опубликована: Окт. 11, 2021

By virtue of a fundamentally new reaction model azomethine ylide serving as two-atom synthon, we present the first example stereodivergent preparation γ-butyrolactones via synergistic Cu/Ir-catalyzed asymmetric cascade allylation/lactonization, and all four stereoisomers bearing two vicinal stereocenters are accessible with excellent diastereoselective enantioselective control. The chiral IrIII -π-allyl intermediate was separated characterized to understand origin regio- stereoselectivity initial C-C bond formation process. Control experiments shed some light on catalyst/substrate catalyst/catalyst interactions in this dual catalytic system rationalize related kinetic/dynamic kinetic resolution process different catalyst combinations. enantioenriched γ-butyrolactone products were converted into an array structurally complex molecules organocatalysts that otherwise inaccessible.

Язык: Английский

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Stereodivergent Construction of 1,4‐Nonadjacent Stereocenters via Hydroalkylation of Racemic Allylic Alcohols Enabled by Copper/Ruthenium Relay Catalysis

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(36)

Опубликована: Июнь 28, 2022

An unprecedented hydroalkylation of racemic allylic alcohols and ketimine esters enabled by Cu/Ru relay catalysis has been developed via merging the ruthenium-catalyzed asymmetric borrowing-hydrogen reaction with a copper-catalyzed Michael addition in one-pot procedure. The current method enables efficient preparation highly functionalized δ-hydroxyesters bearing 1,4-nonadjacent stereocenters good yields high levels diastereoselectivity excellent enantioselectivity under mild conditions. full complement four stereoisomers products could be readily accessed orthogonal permutations two chiral metal catalysts. work highlights power for stereodivergent construction that were otherwise inaccessible.

Язык: Английский

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Stereodivergent Synthesis of Allenes with α,β‐Adjacent Central Chiralities Empowered by Synergistic Pd/Cu Catalysis

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(9)

Опубликована: Янв. 3, 2023

The stereodivergent synthesis of allene compounds bearing α,β-adjacent central chiralities has been realized via the Pd/Cu-catalyzed dynamic kinetic asymmetric alkylation racemic allenylic esters. matched reactivity bimetallic catalytic system enables challenging reaction aryl-substituted acetates with sterically crowded aldimine esters smoothly under mild conditions. Various chiral non-natural amino acids a terminal allenyl group are easily synthesized in high yields and excellent diastereo- enantioselectivities (up to >20 : 1 dr, >99 % ee). Importantly, all four stereoisomers product can be readily accessed by switching configurations two metal catalysts. Furthermore, easy interconversion between uncommon η3 -butadienyl palladium intermediate featuring weak C=C/Pd coordination bond stable Csp2 -Pd is beneficial for transformation process (DyKAT).

Язык: Английский

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Diastereodivergent Aldol‐Type Coupling of Alkoxyallenes with Pentafluorophenyl Esters Enabled by Synergistic Palladium/Chiral Lewis Base Catalysis

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(33)

Опубликована: Июнь 17, 2022

As a fundamental and synthetically useful C-C bond formation reaction, the aldol reaction is one of most versatile transformations in organic synthesis. However, despite extensive research on asymmetric versions unified method for stereoselective access to complementary syn anti diastereomeric products remains be developed. In this study, we developed synergistic palladium/chiral Lewis base system that overcomes inherent diastereoselectivity bias reactions and, as result, allowed us achieve first diastereodivergent coupling alkoxyallenes with pentafluorophenol esters. Computational studies suggest mechanism involving an intermolecular protonative hydropalladation pathway rather than palladium-hydride migratory insertion pathway. The origin stereochemistry catalysis rationalized by DFT calculations.

Язык: Английский

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Dual Catalysis in Organic Synthesis: Current Challenges and New Trends

European Journal of Organic Chemistry, Год журнала: 2022, Номер 26(1)

Опубликована: Дек. 9, 2022

Abstract Dual catalysis is one of the most powerful strategies for development chemical reactions in organic synthesis. This strategy can be divided into cooperative catalysis, relay and sequential according to actual mode operation communication between catalysts. In recent years, such has been applied a large number studies since it advantages of: 1) increasing reactivity enabling challenging transformations; 2) offering way controlling stereoselectivity asymmetric reactions, which traditional catalytic systems; 3) catalyze stereodivergent synthesis molecules bearing or more stereocenters from same starting materials. Perspective, intends introduce reader EurJOC special collection on Catalysis , aims summarize different categories dual demonstrate their benefits constructing new bonds selective manner. Finally, current challenges trends will also presented.

Язык: Английский

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Cooperative Catalyst‐Enabled Regio‐ and Stereodivergent Synthesis of α‐Quaternary α‐Amino Acids via Asymmetric Allylic Alkylation of Aldimine Esters with Racemic Allylic Alcohols

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(46)

Опубликована: Сен. 26, 2022

We describe cooperative bimetallic catalysis that enables regio-/stereodivergent asymmetric α-allylations of aldimine esters. By employing Et3 B as the key activator, racemic allylic alcohols can be directly ionized to form Pd or Ir-π-allyl species in presence achiral chiral Ir complexes, respectively. The less more substituted termini metal-π-allyl are amenable nucleophilic attack by Cu-azomethine ylide, formation which is simultaneously facilitated B, affording α-quaternary α-amino acids with high regioselectivity and excellent stereoselectivity. use readily available electrophilic precursors represents an improvement from environmental atom/step economy perspective. Computational mechanistic studies reveal crucial role additive origins stereo- regioselectivities analyzing steric effects, dispersion interactions, frontier orbital population.

Язык: Английский

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Stereodivergent Construction of Csp³−Csp³Bonds Bearing Vicinal Stereocenters by Synergistic Palladium and Phase‐Transfer Catalysis

Angewandte Chemie International Edition, Год журнала: 2022, Номер 62(2)

Опубликована: Ноя. 16, 2022

Abstract Synergistic catalysis has emerged as one of the most powerful tools for stereodivergent formation Csp 3 −Csp bonds bearing vicinal stereocenters. Despite many successes that have been achieved in this field, coupling reactions involving stabilized nucleophiles remain challenging because competing single‐catalysis pathway. Herein, we report a synergistic palladium/phase‐transfer catalyst system enables diastereodivergent 1,3‐dienes with nucleophile oxindoles. Both syn and anti products, quaternary tertiary stereocenters, could be selectively produced good yields high enantio‐ diastereoselectivities. Non‐covalent activation via chiral ion pair biphasic is crucial success factor achieving diastereodivergence.

Язык: Английский

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Synergistic Palladium/Copper‐Catalyzed 1,4‐Difunctionalization of 1,3‐Dienes for Stereodivergent Construction of 1,5‐Nonadjacent Stereocenters

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(21)

Опубликована: Март 21, 2024

Abstract The construction of two distal stereocenters through a single catalytic process is great interest in organic synthesis. While there are some successful reports regarding stereodivergent preparation 1,3‐ or 1,4‐stereocenters, the more challenged 1,5‐nonadjacent have never been achieved fashion. Herein we describe synergistic palladium/copper catalysis for 1,4‐difunctionalization reactions 1,3‐dienes, providing access to quaternary stereocenters. Because each catalysts separately controlled one newly formed stereocenters, synthesis all four diastereomers products could readily be simply by choosing an appropriate combination chiral catalysts. Experimental and computational studies supported mechanism involving Heck/Tsuji–Trost cascade reaction, origins stereoselectivity were elucidated.

Язык: Английский

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