Recent advances in the metal-catalyzed asymmetric synthesis of chiral allenes

Organic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(18), P. 5053 - 5073

Published: Jan. 1, 2022

Recent advances in the metal-catalyzed asymmetric synthesis of chiral allenes are summarized. This review is categorized based on starting material, including alkynes, racemic allenes, and conjugated dienes.

Language: Английский

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Pd/Xu-Phos-catalyzed asymmetric elimination of fully substituted enol triflates into axially chiral trisubstituted allenes

Science Advances, Journal Year: 2023, Volume and Issue: 9(11)

Published: March 17, 2023

The β-H elimination, as one of the most important elementary reactions in transition metal chemistry, is a key step quenching carbon-palladium bond for Heck reaction. However, elimination alkenyl palladium species leading to allene an energetically unfavored process, and therefore, it has been long-standing challenge control this process via enantioselective manner. We developed concise efficient methodology construct trisubstituted chiral allenes from stereodefined fully substituted enol triflates by under mild conditions. identified Xu-Phos play crucial role chemoselectivity enantioselectivity. Multiple linear regression analysis shows steric effect on DFT computation results allow us propose intramolecular base (-OAc)-assisted deprotonation mechanism progress. Distortion-interaction energy decomposition indicate that difference electrostatic (Eelec) two base-assisted states dominates stereoselectivity.

Language: Английский

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Highlighting the Rich Chemistry of the Allenone Moiety

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(9), P. 1332 - 1384

Published: March 14, 2023

Abstract Conjugated and non‐conjugated allenones appear as recurring motifs in organic synthesis, natural products mechanistic investigations showing unique properties applications. The ability of to build cycles has provided a direct access strained systems, medium‐sized rings, arenes, heterocycles complex polycycles. In addition, have served models catalysis. critic compilation herein presented will provide an exhaustive overview the synthetic possibilities may offer, which certainly inspire our community their search more efficient methodologies, preparation biological pharmaceutical targets, improve knowledge theoretical chemistry. Great part this review discuss aspects, catalysis innovation insights chemical transformations implying allenone motif. many examples on total synthesis pharmacologically active compounds be described. We hope that attractive chemistry, catalysis, medicinal chemistry communities. magnified image

Language: Английский

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Transition‐Metal Catalyzed Stereoselective Desymmetrization of Prochiral Cyclohexadienones

The Chemical Record, Journal Year: 2021, Volume and Issue: 21(12), P. 3689 - 3726

Published: June 19, 2021

The development of transition-metal catalyzed enantioselective and diastereoselective transformations has contributed many advances in the field synthetic organic chemistry. Particularly, stereoselective desymmetrization prochiral cyclohexadienones represents a powerful strategy for accessing highly functionalized stereochemically enriched scaffolds, which are often found biologically active compounds natural products. In recent years, several research groups including our group have made significant progress on desymmetrizations 2,5-cyclohexadienones. this account, we will provide an overview developments area employing Pd, Cu, Rh, Au, Ag, Ni, Co, Mn-catalysts.

Language: Английский

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Chiral bisphosphine Ph-BPE ligand: a rising star in asymmetric synthesis

Chemical Society Reviews, Journal Year: 2024, Volume and Issue: 53(13), P. 6735 - 6778

Published: Jan. 1, 2024

The review summarizes the increasing applications of chiral bisphosphine ligand Ph-BPE in catalytic asymmetric reactions past twenty years.

Language: Английский

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Cross-coupling of organic fluorides with allenes: a silyl-radical-relay pathway for the construction of α-alkynyl-substituted all-carbon quaternary centres

Chemical Science, Journal Year: 2024, Volume and Issue: 15(14), P. 5113 - 5122

Published: Jan. 1, 2024

Cross-coupling of organic fluorides with allenes via radical rearrangement to afford all-carbon quaternary centres mediated by silylboronate/potassium tert -butoxide is disclosed.

Language: Английский

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Alkoxyl Radical-Mediated Ring Expansion/1,4-Difunctionalization of 1,3-Enynes upon Copper Catalysis

Organic Letters, Journal Year: 2023, Volume and Issue: 25(30), P. 5563 - 5568

Published: July 21, 2023

A redox-neutral copper-catalyzed cascade reaction involving alkoxyl radical-mediated ring expansion/1,4-difunctionalization of 1,3-enynes was developed, offering a straightforward approach to the tetra-substituted allenes with macrolactone, CN, and CF3 functional groups. Remarkably, incorporation NH2 group onto 1,3-enyne moiety enabled further cyclization give unique scaffold containing lactone an indole moiety.

Language: Английский

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Copper(I)-catalyzed asymmetric 1,3-dipolar cycloaddition of 1,3-enynes and azomethine ylides

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 4, 2023

Herein, we report a copper(I)-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides and 1,3-enynes, which provides series chiral poly-substituted pyrrolidines in high regio-, diastereo-, enantioselectivities. Both 4-aryl-1,3-enynes 4-silyl-1,3-enynes serve as suitable dipolarophiles while 4-alkyl-1,3-enynes are inert. Moreover, the method is successfully applied construction both tetrasubstituted stereogenic carbon centers spiro pyrrolidines. The DFT calculations also conducted, imply concerted mechanism rather than stepwise mechanism. Finally, various transformations started from pyrrolidine bearing triethylsilylethynyl group centered on alkyne achieved, compensates for inertness present reaction.

Language: Английский

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Recent Advances in the Synthesis of Chiral Allenes via Asymmetric 1,4‐Difunctionalization of 1,3‐Enynes

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(30)

Published: March 22, 2024

Abstract Allenes represent a distinctive class of organic molecules characterized by their unique physical and chemical properties. Among them, chiral allenes play significant role in modern chemistry. They not only serve as pivotal frameworks for natural products drug but also are essential building blocks synthesis. Over the years, numerous remarkable efficient methods have been developed synthesis allenes. Notably, catalytic using transition metals conjunction with ligands has garnered considerable attention. This review paper aims to provide an overview recent advancements through asymmetric 1,4‐difunctionalization 1,3‐enynes, which two distinct strategies including non‐radical radical processes highlighted.

Language: Английский

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Ene-Reductase-Catalyzed Enantioselective Desymmetrization of Cyclohexadienones: Straightforward Access to All-Carbon Quaternary Stereocenters

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(8), P. 6194 - 6202

Published: April 8, 2024

An unprecedented enzyme-catalyzed enantioselective desymmetrization of achiral 2,5-cyclohexadienones has been reported. Using ene-reductases as the biocatalysts, a variety γ,γ-disubstituted cyclohexadienones were reduced to respective chiral cyclohexenones bearing an all-carbon quaternary stereocenter in high yields (up 96%) along with low levels over-reduction (less than 4% cyclohexanones most cases) and good enantioselectivities (mostly 99% ee), which are superior obtained chemocatalysis. A mutagenesis study indicated residue Q232 was likely important for NCR providing selectively over cyclohexanones, molecular dynamics (MD) simulations performed rationalize enantioselectivity level observed this enzyme. The deuterium-labeling experiment suggested hydrogen at N5 atom flavin cofactor added face substrate 1a that bulkier phenyl group facing toward it. current work expands scope ene-reductases, efficient, stereoselective access valuable cyclohexenones, will stimulate development other classes cyclohexadienones.

Language: Английский

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