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

Chemical Reviews, Год журнала: 2021, Номер 121(8), С. 4373 - 4505

Опубликована: Март 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.

Язык: Английский

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Catalytic Enantioselective Ring-Opening Reactions of Cyclopropanes

Chemical Reviews, Год журнала: 2020, Номер 121(1), С. 227 - 263

Опубликована: Май 29, 2020

This review describes the development of enantioselective methods for ring opening cyclopropanes. Both approaches based on reaction nonchiral cyclopropanes and (dynamic) kinetic resolutions asymmetric transformations chiral substrates are presented. The is organized according to substrate classes, starting by more mature field donor-acceptor Emerging acceptor- or donor-only then last part reactive three-membered rings substituted with unsaturations a particular focus vinylcyclopropanes, alkylidenecyclopropanes, vinylidenecyclopropanes. In two decades, has grown from proof concept stage broad range accessing enantioenriched building blocks, further extensive developments can be expected in future.

Язык: Английский

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Transition Metal-Catalyzed Selective Carbon–Carbon Bond Cleavage of Vinylcyclopropanes in Cycloaddition Reactions

Chemical Reviews, Год журнала: 2020, Номер 121(1), С. 110 - 139

Опубликована: Авг. 6, 2020

In this review, transition metal-catalyzed methodologies and applications that exploit C–C bond cleavage of vinylcyclopropanes (VCPs) are summarized with a focus on cycloaddition related addition reactions. Transition metals, including palladium, nickel, iron, ruthenium, rhodium, cobalt, iridium, can catalyze the bonds in activated or nonactivated VCPs. Additionally, these bond-breaking reactions occur as intra- intermolecular processes. The properties VCPs discussed Introduction. Various involving then next chapter. cycloadditions following Finally, challenges potential opportunities outlined last

Язык: Английский

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Enantioselective Dicarbofunctionalization of Unactivated Alkenes by Palladium‐Catalyzed Tandem Heck/Suzuki Coupling Reaction

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(41), С. 14653 - 14659

Опубликована: Авг. 17, 2019

Abstract A highly enantioselective dicarbofunctionalization of unactivated alkenes was implemented by a Pd‐catalyzed asymmetric tandem Heck/Suzuki coupling reaction. This reaction represents the first example intramolecular cyclization/cross‐coupling olefin‐tethered aryl halides with alkyl‐, alkenyl‐ or arylboronic acids, and provides rapid access to number chiral compounds, such as dihydrobenzofurans, indolines, chromanes, indanes bearing quaternary stereocenter, in good yields excellent enantioselectivities. The practicality this validated modification biologically complex molecules peptides, piperitol, CB2 receptor agonists, etc. Moreover, synthesis two enantiomers can be easily realized simple change order steps sequence.

Язык: Английский

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Recent Advances in Metal‐Catalyzed Functionalization of Indoles

Advanced Synthesis & Catalysis, Год журнала: 2021, Номер 363(11), С. 2723 - 2739

Опубликована: Апрель 7, 2021

Abstract Indole is one of the most important heterocycles in organic synthesis, natural products, and drug discovery. Recently, tremendous advances selective functionalization indoles have been reported. Although powered by transition metal catalysis, exceedingly useful methods absence metals also In this review, we provide an overview reactions that published last years with a focus on recent advances, aims, future trends. The review organized positional selectivity type used for functionalization. particular, discuss major transition‐metal‐catalyzed C−H at classical C2/C3 positions, remote C4/C7 cross‐coupling, transition‐metal‐free magnified image

Язык: Английский

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Kinetic Studies of Donor–Acceptor Cyclopropanes: The Influence of Structural and Electronic Properties on the Reactivity

Angewandte Chemie International Edition, Год журнала: 2018, Номер 58(7), С. 1955 - 1959

Опубликована: Дек. 18, 2018

The kinetics of (3+2) cycloaddition reactions 18 different donor-acceptor cyclopropanes with the same aldehyde were studied by in situ NMR spectroscopy. Increasing electron density donor residue accelerates reaction a factor up to 50 compared standard system (donor group=phenyl), whereas electron-withdrawing substituents slow down 660. This behavior is agreement Hammett substituent parameter σ. obtained rate constants from cycloadditions correlate well data additionally (3+n) nitrone (n=3) and an isobenzofuran (n=4). A comparison kinetic bond lengths cyclopropane (obtained X-ray diffraction computation), or 1 H 13 C shifts, revealed no correlation. However, computed relaxed force proved be good indicator for reactivity three-membered ring.

Язык: Английский

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Enantioselective Difunctionalization of Alkenes by a Palladium‐Catalyzed Heck/Sonogashira Sequence

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(7), С. 2769 - 2775

Опубликована: Ноя. 22, 2019

Abstract Sonogashira‐type cross‐couplings are one of the most significant alkynylations in organic chemistry. One first palladium‐catalyzed intramolecular Heck/Sonogashira reactions alkenes with terminal alkynes is now reported. With this method, a variety uniquely substituted chiral benzene‐fused heterocycles bearing propargyl‐substituted all‐carbon quaternary stereocenter were obtained straightforward, high‐yielding, and highly stereoselective manner under mild conditions. Salient features process include use readily available substrates, high selectivities, broad substrate scope as well versatile product functionalizations.

Язык: Английский

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Pd‐Catalyzed Dearomatization of Anthranils with Vinylcyclopropanes by [4+3] Cyclization Reaction

Angewandte Chemie International Edition, Год журнала: 2019, Номер 58(17), С. 5739 - 5743

Опубликована: Фев. 27, 2019

Abstract Dearomatization of anthranils with vinylcyclopropanes (VCPs) by Pd‐catalyzed [4+3] cyclization reaction has been realized. In the presence a catalytic amount borane as an activator, bridged cyclic products were obtained in good to excellent yields stereoselectivities. By introducing chiral PHOX ligand ( L5 ), asymmetric dearomatization reactions proceeded enantioselectivity. Borane plays key role for reactivity, likely owing formation borane–anthranil complex which confirmed NMR experiments.

Язык: Английский

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Regio‐ and Enantioselective Synthesis of Sulfone‐Bearing Quaternary Carbon Stereocenters by Pd‐Catalyzed Allylic Substitution

Angewandte Chemie International Edition, Год журнала: 2019, Номер 59(3), С. 1340 - 1345

Опубликована: Сен. 10, 2019

Abstract Chiral sulfones are of great importance in medicinal chemistry and chemical synthesis. Efficient methods for preparing enantiomerically enriched sulfone‐containing molecules can therefore be significant value; such methods, however, uncommon. Herein, we report the first general palladium‐catalyzed sulfonylation vinyl cyclic carbonates with sodium sulfinates. A series tertiary allylic were synthesized good yields excellent enantiomeric ratios. Both aliphatic‐ aryl‐substituted suitable reactants results. This reaction features broad substrates scope, readily available starting materials, regio‐ enantioselectivity, synthesis sulfone‐bearing quaternary carbon stereocenters. Through geranyl derived carbonate 1 h , achieve formal total (+)‐agelasidine A.

Язык: Английский

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Tandem Allylation/1,2-Boronate Rearrangement for the Asymmetric Synthesis of Indolines with Adjacent Quaternary Stereocenters

Journal of the American Chemical Society, Год журнала: 2018, Номер 140(41), С. 13242 - 13252

Опубликована: Сен. 21, 2018

A three-component coupling using lithiated indoles, boronate esters and allylic acetates generates chiral indolines with adjacent quaternary stereocenters. Successful stereocontrol required the use of phosphoramidite ligands not previously described for organopalladium chemistry. Mechanistic studies indicate a monodentate PdL intermediate, stepwise allylation-aryl/alkyl migration. protodeborylation strategy was used to install C–H bond in place C–B bond. photoredox replace C–C highly diastereoselective manner. In specific case methyl-vinyl ketone, novel radical-mediated annulation provides polycyclic products high enantio- diastereoselectivity.

Язык: Английский

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