Alkynyl cyclopropanes in organic synthesis

Russian Chemical Bulletin, Год журнала: 2024, Номер 73(1), С. 53 - 109

Опубликована: Янв. 1, 2024

Язык: Английский

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New‐Generation Ligand Design for the Gold‐Catalyzed Asymmetric Activation of Alkynes

ChemPlusChem, Год журнала: 2021, Номер 86(9), С. 1283 - 1296

Опубликована: Июль 12, 2021

Abstract Gold(I) catalysts are ideal for the activation of alkynes under very mild conditions. However, unlike allenes or alkenes, triple bond cannot be prochiral. In addition, linear coordination displayed by gold(I) complexes places chiral ligand far away from substrate resulting in an inefficient transfer information. This poses a significant challenge achievement high enantiocontrol gold(I)‐catalyzed reactions alkynes. Although considerable progress on enantioselective transformations has recently been achieved, asymmetric non‐prochiral alkyne‐containing small molecules still represents great challenge. Herein we summarize recent advances intra‐ and intermolecular involving alkynes, discussing new designs that lie at basis these developments. We also focus mode action catalysts, their possible limitations towards next‐generation more efficient designs. Finally, square planar gold(III) complexes, which offer alternative to discussed.

Язык: Английский

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Simultaneous construction of axial and planar chirality by gold/TY-Phos-catalyzed asymmetric hydroarylation

Nature Communications, Год журнала: 2021, Номер 12(1)

Опубликована: Июль 29, 2021

Abstract The simultaneous construction of two different chiralities via a simple operation poses considerable challenge. Herein cationic gold-catalyzed asymmetric hydroarylation ortho-alkynylaryl ferrocenes derivatives is developed, which enable the axial and planar chirality. here identified TY-Phos derived gold complex responsible for high yield, good diastereoselectivity (>20:1 dr), enantioselectivities (up to 99% ee) mild conditions. catalyst system also shows potential application in synthesis chiral biaryl compounds. cause enantioselectivity this investigated with density functional theory caculation.

Язык: Английский

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Ligand-Enabled Sustainable Gold Catalysis

ACS Sustainable Chemistry & Engineering, Год журнала: 2022, Номер 10(21), С. 6900 - 6918

Опубликована: Май 16, 2022

Gold catalysis has emerged as an efficient tool in the field of synthetic organic chemistry. Despite significant progress, need for high catalyst loadings mainly hampered its applicability large-scale synthesis. Recent research showcased importance ligand engineering to realize gold-catalyzed transformations at low loadings, milder reactions conditions, and greener solvents. In this perspective, we summarized reports that clearly emphasize crucial role ligands achieving highly catalysts (≤0.1 mol %) with turnover numbers frequencies. This perspective also briefly discusses challenges future potential development ppm-level gold catalysis.

Язык: Английский

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Enantioselective Total Synthesis of (+)-Aberrarone

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(34), С. 15475 - 15479

Опубликована: Авг. 19, 2022

We disclose the first total synthesis of (+)-aberrarone, a diterpenoid natural product featuring 5-5-5-6-fused tetracyclic skeleton. Key to approach is Au-catalyzed-Sn-mediated Meyer-Schuster-Nazarov-cyclopropanation-aldol cascade, which closes four rings in high yield. The convergent furnishes (+)-aberrarone stereoselectively 15 steps. highlight benefits using Sn-alkoxide considerably expand opportunities Au-catalysis for complex molecules.

Язык: Английский

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Pd(II)-Catalyzed Enantioselective C(sp³)–H Arylation of Cyclopropanes and Cyclobutanes Guided by Tertiary Alkylamines

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(9), С. 3939 - 3948

Опубликована: Фев. 25, 2022

Strained aminomethyl-cycloalkanes are a recurrent scaffold in medicinal chemistry due to their unique structural features that give rise range of biological properties. Here, we report palladium-catalyzed enantioselective C(sp3)-H arylation aminomethyl-cyclopropanes and -cyclobutanes with aryl boronic acids. A native tertiary alkylamine groups able direct C-H cleavage forge carbon-aryl bonds on the strained cycloalkanes framework as single diastereomers excellent enantiomeric ratios. Central success this strategy is use simple N-acetyl amino acid ligand, which not only controls enantioselectivity but also promotes γ-C-H activation over other pathways. Computational analysis cyclopalladation step provides an understanding how occurs revealed distinct transition structures our previous work desymmetrization N-isobutyl alkylamines. This straightforward operationally method simplifies construction functionalized aminomethyl-strained cycloalkanes, believe will find widespread academic industrial settings relating synthesis biologically active small molecules.

Язык: Английский

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Enantioselective Synthesis of Biscyclopropanes Using Alkynes as Dicarbene Equivalents

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(29)

Опубликована: Май 22, 2023

Chiral biscyclopropanes are an important skeleton in many bioactive molecules. However, there few routes to synthesize these molecules with high stereoselectivity due the nature of multiple stereocenters. Herein, we report first example Rh2 (II)-catalyzed enantioselective synthesis bicyclopropanes alkynes as dicarbene equivalents. The 4-5 vicinal stereocenters and 2-3 all-carbon quaternary centers were constructed excellent stereoselectivity. This protocol features efficiency functional group tolerance. Moreover, was also extended cascaded cyclopropanation/cyclopropenation stereoselectivities. In processes, both sp-carbons alkyne converted into stereogenic sp3 -carbons. Experimental density theory (DFT) calculations revealed that cooperative weak hydrogen bonds between substrates dirhodium catalyst may play key roles this reaction.

Язык: Английский

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Gold-catalyzed cyclization and cycloaddition in natural product synthesis

Natural Product Reports, Год журнала: 2024, Номер 41(7), С. 1091 - 1112

Опубликована: Янв. 1, 2024

This review highlights a curated selection of publications utilizing homogeneous gold-catalyzed cycloaddition and cyclization reactions for the total synthesis natural products reported from 2016 to mid-2023.

Язык: Английский

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Enantioselective [2+2] Cycloaddition of Allenyl Imide with Mono‐ or Disubstituted Alkenes

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(44)

Опубликована: Сен. 14, 2022

Abstract An efficient catalytic asymmetric [2+2] cycloaddition of allenyl imide and mono‐ or disubstituted alkenes is disclosed. The key feature this method the use bidentate weakly activated less steric hindered alkene pair by utilizing chiral magnesium(II) complex N , N′ ‐dioxide, which could provide through‐space dispersion interactions to orientate arrangement alkene. This protocol allows generation a series axially cyclobutenes four‐membered ring‐containing spirocycles (80 examples) in high yield (up 99 %) with excellent enantioselectivity >99 % ee ), late‐stage modification biologically active molecules as well. Experimental studies DFT calculations revealed that proceeded via stepwise mechanism involving short‐lived zwitterionic intermediate. π‐π interaction between amide moiety ligand was crucial for enantiocontrol.

Язык: Английский

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Valence Tautomerism Induced Proton Coupled Electron Transfer:X−H Bond Oxidation with a Dinuclear Au(II) Hydroxide Complex

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(14)

Опубликована: Фев. 7, 2024

Abstract We report the preparation and characterization of dinuclear Au II hydroxide complex 2 (L) (OH) (L= N , N′ ‐bis (2,6‐dimethyl) phenylformamidinate) study its reactivity towards weak X−H bonds. Through interplay kinetic analysis computational studies, we demonstrate that oxidation cyclohexadiene follows a concerted proton‐coupled electron transfer (cPCET) mechanism, rare type for complexes. find Au−Au σ‐bond undergoes polarization in PCET event leading to an adjustment levels both centers prior C(sp 3 )−H bond cleavage. thus describe as valence tautomerism‐induced where basicity one reduced Au−OH unit provides proton acceptor second more oxidized center serves acceptor. The coordination these events allows unprecedented radical‐type by closed shell complex.

Язык: Английский

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