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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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 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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Synergistic Pd/Amine-Catalyzed Stereodivergent Hydroalkylation of 1,3-Dienes with Aldehydes: Reaction Development, Mechanism, and Stereochemical Origins

Journal of the American Chemical Society, Journal Year: 2021, Volume and Issue: 143(29), P. 10948 - 10962

Published: July 15, 2021

Metal-hydride-catalyzed hydroalkylation of 1,3-dienes with enolizable carbonyl compounds is an atom- and step-economical method for preparing chiral molecules allylic stereocenters. Although high diastereo- enantioselectivities have been achieved many coupling partners, aldehydes not yet used this purpose because they are less stable than other under basic conditions the potential to rapidly epimerize at α-position. Moreover, stereodivergent reactions access complementary diastereomers vicinal stereocenters challenging. Herein, we describe a synergistic palladium/amine catalyst system that allowed us achieve first aldehydes. By choosing appropriate combination palladium amine catalysts, could obtain either syn or anti products, therefore provides highly enantioselective α,β-vicinal Density functional theory calculations revealed mechanism involving PdH formation migratory insertion into alkene, followed by C–C bond formation. The origin stereoselectivities was investigated means distortion/interaction analysis.

Language: 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, Journal Year: 2021, Volume and Issue: 60(47), P. 24930 - 24940

Published: Oct. 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.

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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Stereodivergent total synthesis of rocaglaol initiated by synergistic dual-metal-catalyzed asymmetric allylation of benzofuran-3(2H)-one

Chem, Journal Year: 2022, Volume and Issue: 8(7), P. 2011 - 2022

Published: May 2, 2022

Language: Английский

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