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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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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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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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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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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Further Developments and Applications of Oxazoline-Containing Ligands in Asymmetric Catalysis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 121(11), P. 6373 - 6521

Published: May 21, 2021

The chiral oxazoline motif is present in many ligands that have been extensively applied a series of important metal-catalyzed enantioselective reactions. This Review aims to provide comprehensive overview the most significant applications oxazoline-containing reported literature starting from 2009 until end 2018. are classified not by reaction which their metal complexes but nature denticity, chirality, and donor atoms involved. As result, continued development ligand architectural design mono(oxazolines), bis(oxazolines), tris(oxazolines) tetra(oxazolines) variations thereof can be more easily monitored reader. In addition, key transition states selected asymmetric transformations will given illustrate features give rise high levels induction. further aid reader, we summarize majority schemes with representative examples highlight variation % yields ees for carefully substrates. should particular interest experts field also serve as useful point new researchers this area. It hoped stimulate both development/design novel transformations.

Language: Английский

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Dispersion and Steric Effects on Enantio-/Diastereoselectivities in Synergistic Dual Transition-Metal Catalysis

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(4), P. 1971 - 1985

Published: Jan. 20, 2022

Comprehensive computational studies were carried out to explore the mechanisms of enantioselective Cu/Pd and stereodivergent Cu/Ir dual-catalytic syntheses α,α-disubstituted α-amino acids (α-AAs). A chiral copper azomethine ylide undergoes facile α-allylation with racemic π-allylpalladium species or stereopure π-allyliridium complex stereoconvergently stereodivergently furnish single/double stereocenters, respectively. Stereoselectivity at α-center is controlled by facial selectivity respect prochiral nucleophile. Despite apparently similar transition-state assemblies, models distortion/interaction analyses disclose versatile modes stereoinduction wherein can face-selectively intercept metal−π-allyl intermediates utilizing attractive dispersion interactions and/or sterically caused distortions. Generation β-stereocenter in system relies on a stereospecifically generated allyliridium electronically branched-to-linear selectivity, while dual yields linear monochiral product due steric factors π–π stacking interactions. The demonstrate molecular level how ligand-encoded information transferred α-/β-sites resulting α-AAs mode regio-/stereoselection altered differences transition-metal-stabilized coupling partners. To facilitate stereoselective catalysis, suite analytical tools extract controlling for asymmetric induction demonstrated.

Language: Английский

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Synergistic Pd/Cu Catalysis in Organic Synthesis

Chemistry - A European Journal, Journal Year: 2019, Volume and Issue: 26(22), P. 4895 - 4916

Published: Nov. 25, 2019

Synergistic Pd/Cu catalysis has been utilized in the Sonogashira reaction since 1975. However, this strategy not received much attention from organic chemist community until recently. is becoming a proficient method for development of catalytic reactions, including several new and efficient cross-coupling reactions. Additionally, challenging asymmetric stereodivergent synthesis, have discovered by combined use chiral metal catalyst second achiral or two catalysts. This review provides an overview field, with aims highlighting both synergistic synthesis mechanisms involved research area.

Language: Английский

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Cooperative Ni/Cu‐Catalyzed Asymmetric Propargylic Alkylation of Aldimine Esters

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(34), P. 14270 - 14274

Published: May 18, 2020

A novel Ni/Cu dual catalysis gives rise to fundamentally new cooperative reactivity and enables the regio- enantioselective propargylic alkylation reaction. diverse set of α-quaternary propargylated amino ester derivatives were synthesized in good yields with excellent enantioselectivity (up 99 % ee). This work highlights power catalysis, which can be expected have broad implications homogeneous beyond highly valuable synthetic intermediates.

Language: Английский

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