Recent Advances in Enantioselective Pd-Catalyzed Allylic Substitution: From Design to Applications

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(8), P. 4373 - 4505

Published: March 19, 2021

This Review compiles the evolution, mechanistic understanding, and more recent advances in enantioselective Pd-catalyzed allylic substitution decarboxylative oxidative substitutions. For each reaction, catalytic data, as well examples of their application to synthesis complex molecules, are collected. Sections which we discuss key aspects for high selectivity a comparison with other metals (with advantages disadvantages) also included. asymmetric substitution, data grouped according type nucleophile employed. Because prominent position use stabilized carbon nucleophiles heteronucleophiles, many chiral ligands have been developed. To better compare results, they presented by ligand types. reactions mainly promoted PHOX or Trost ligands, justifies organizing this section chronological order. results used.

Language: Английский

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Asymmetric synthesis of allylic compoundsviahydrofunctionalisation and difunctionalisation of dienes, allenes, and alkynes

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 49(7), P. 2060 - 2118

Published: Jan. 1, 2020

This review article provides an overview of progress in asymmetric synthesis allylic compoundsviahydrofunctionalisation and difunctionalisation dienes, allenes, alkynes.

Language: Английский

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Catalytic Asymmetric Reactions with N-Metallated Azomethine Ylides

Accounts of Chemical Research, Journal Year: 2020, Volume and Issue: 53(5), P. 1084 - 1100

Published: April 22, 2020

ConspectusOptically active nitrogen-containing compounds have attracted substantial attention due to their ubiquity in the cores of natural products and bioactive molecules. Among various synthetic approaches nitrogenous frameworks, catalytic asymmetric 1,3-dipolar cycloadditions are one most attractive methods because powerful ability rapidly construct chiral N-heterocycles. In particular, N-metallated azomethine ylides, common readily available 1,3-dipoles, been extensively applied dipolar cycloaddition reactions. Despite fact that transformations ylides investigated for decades, efforts directed toward preparation pyrrolidines using glycinate-derived α-unsubstituted aldimine esters as precursors ylides. While α-substituted derived from amino other than glycinate seldom harnessed, construction non-five-membered N-heterocycles via remains underexplored. addition, α-functionalization prepare acyclic such α-amino acids, which an situ-generated ylide serves nucleophile, has not sufficiently described.In this Account, we mainly discuss achievements made past decade broadening applications compounds. We began our investigation with design synthesis a new type ligand, TF-BiphamPhos, only coordinates Lewis acids activate species but also H-bond donor increase reactivity dipolarophiles significantly enhanced stereochemical control. Using Cu(I) or Ag(I)/TF-BiphamPhos complex catalyst, achieved highly stereoselective (3+2) non-glycinate-derived diverse dipolarophiles, producing variety enantioenriched multiple stereocenters single step. To further expand utility successfully developed higher order fulvenes, tropone, 2-acyl cycloheptatrienes, pyrazolidinium serving reaction partner, provides straightforward access fused piperidines, bridged azabicyclic triazines (3+6)- (3+3)-type cycloadditions. realized Cu(I)-catalyzed 1,4-Michael additions α,β-unsaturated bisphosphates/Morita–Baylis–Hillman products, furnishing array structurally unnatural acids. Based on strategy synergistic activation, efficient dual Cu/Pd Cu/Ir catalysis allylic/allenylic alkylation Notably, allowed stereodivergent α,α-disubstituted branched allylic reaction, two distinct metal catalysts independently full control over corresponding nucleophile electrophile. Furthermore, expedient biologically important tetrahydro-γ-carbolines was through Cu/Ir-catalyzed cascade allylation/iso-Pictet–Spengler cyclization. when steric congestion allylation intermediates increased, combined provided allylation/2-aza-Cope rearrangement, optically homoallylic amines impressive results.

Language: Английский

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Challenges and Opportunities in Multicatalysis

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(7), P. 3891 - 3915

Published: March 15, 2021

Multicatalysis is an emerging field targeting the development of efficient catalytic transformations to quickly convert relatively simple starting materials into more complex value-added products. Within multicatalytic processes either multiple catalysts execute single reactions or precise sequences occur in a "one-pot" fashion. Attractively, protocols not only enable that are inaccessible through classic approaches but also able significantly reduce time, waste, and cost synthetic processes, making organic synthesis resources efficient. In this Perspective article, we review different strategies multicatalysis bring distinct challenges opportunities. We divide overarching three main categories: cooperative, domino, relay catalysis. Each category described along with representative examples highlight its features. Special emphasis dedicated catalysis, which further discussed subcategories. Lastly, provide analysis systems incorporate higher levels complexity underscore potential systems.

Language: Английский

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Stereodivergent Pd/Cu Catalysis for the Dynamic Kinetic Asymmetric Transformation of Racemic Unsymmetrical 1,3-Disubstituted Allyl Acetates

Journal of the American Chemical Society, Journal Year: 2020, Volume and Issue: 142(18), P. 8097 - 8103

Published: April 19, 2020

A stereodivergent Pd/Cu catalyst system has been developed for the unprecedented dynamic kinetic asymmetric transformation (DyKAT) of racemic unsymmetrical 1,3-disubstituted allylic acetates with prochiral aldimine esters. series α,α-disubstituted α-amino acids bearing vicinal stereocenters were easily prepared excellent enantioselectivities (up to >99% ee) and diastereoselectivities >20:1 dr). Moreover, all four stereoisomers product can be readily obtained simply by switching configurations two chiral metal catalysts. Furthermore, present work highlights power synergistic catalysis consisting common bidentate ligands synthesis.

Language: Английский

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Catalytic Enantio- and Regioselective Addition of Nucleophiles in the Intermolecular Hydrofunctionalization of 1,3-Dienes

ACS Catalysis, Journal Year: 2019, Volume and Issue: 10(2), P. 1060 - 1076

Published: Dec. 12, 2019

Catalytic enantioselective synthesis of small-molecule building blocks with allylic stereogenic centers is an important objective in organic synthesis, but preparing this motif wherein the adjacent olefin 1,2-disubstituted a single step tremendous challenge. Late-transition-metal-catalyzed intermolecular couplings nucleophiles and 1,3-dienes hydrofunctionalization reactions have quickly emerged as compelling approach to these related compounds. In Perspective, we illustrate how diene hydrofunctionalizations provided avenue complex, highly desirable chemical space that not readily accessed by other technologies. We also aim provide some insight into varying mechanistic pathways nuances myriad help inform future reaction catalyst design.

Language: Английский

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Stereodivergent Synthesis of Tertiary Fluoride-Tethered Allenes via Copper and Palladium Dual Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(19), P. 7285 - 7291

Published: May 10, 2021

Herein we describe a protocol for the unprecedented stereodivergent synthesis of tertiary fluoride-tethered allenes bearing stereogenic center and axis via Cu/Pd synergistic catalysis. A broad scope conjugated enynes are coupled with various α-fluoroesters in high yields diastereoselectivities generally >99% ee. In addition, four stereoisomers allene products ensure precise access to corresponding fluorinated hydrofurans novel axial-to-central chirality transfer process.

Language: Английский

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Enantio- and Diastereodivergent Construction of 1,3-Nonadjacent Stereocenters Bearing Axial and Central Chirality through Synergistic Pd/Cu Catalysis

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(32), P. 12622 - 12632

Published: Aug. 5, 2021

In contrast to the widely explored methods for asymmetric synthesis of molecules bearing a single stereocenter or adjacent stereocenters, concurrent construction 1,3-stereogenic centers in an enantio- and diastereoselective manner remains challenge, especially acyclic systems. Herein, we report diastereodivergent 1,3-nonadjacent stereocenters allenyl axial central chirality through synergistic Pd/Cu-catalyzed dynamic kinetic allenylation with racemic allenylic esters. The protocol is suitable wide range substrates including challenging esters less sterically bulky substituents provided chiral products high levels diastereoselectivities (up >20:1 dr >99% ee). Furthermore, several representative transformations involving axial-to-central transfer were conducted, affording useful structural motifs containing nonadjacent manner.

Language: Английский

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Bimetallic Catalysis in Stereodivergent Synthesis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(45)

Published: Aug. 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.

Language: 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, Journal Year: 2021, Volume and Issue: 60(47), P. 24941 - 24949

Published: Sept. 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.

Language: Английский

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