Interrupting Associative π–σ–π Isomerization Enables Z-Retentive Asymmetric Tsuji–Trost Reaction

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: 147(3), P. 2776 - 2785

Published: Jan. 8, 2025

The asymmetric Tsuji-Trost reaction has been extensively studied due to its importance in establishing stereogenic centers, often adjacent an E-olefin moiety organic molecules. generally preferential formation of chiral products is believed result from the thermodynamically more stable syn-π-allylpalladium intermediate. rapid associative π-σ-π isomerization makes it challenging synthesize Z-olefin via transient anti-π-allylpalladium Herein, we report a strategy for regulating by tuning steric bulkiness ligands, allylic leaving groups, and counteranions. utilization Pd catalyst derived phosphoramidite ligands interrupts isomerization, enabling highly efficient Z-retentive toward array α-amino acid derivatives bearing motif high yields (up 95%) excellent stereoselectivity 99% ee >19:1 Z/E) with low loading (0.1 mol %). mechanistic insights design reported this work pave way rational developments Tsuji-Trost-type reactions.

Language: Английский

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Synthesis of Medium-Sized Rings by Z-Retentive Asymmetric Allylic Substitution-Enabled Intermolecular Cascade Cyclization under Iridium/Cinchona Catalysis

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(20), P. 15743 - 15750

Published: Oct. 9, 2024

Medium-sized rings are important structural units in organic molecules of significant interest. However, their efficient synthesis, especially a highly enantioselective manner, has been formidable challenge. Herein, we report an synthesis medium-sized aza-rings by Z-retentive asymmetric allylic substitution-enabled intermolecular cascade cyclization via iridium/cinchona dual catalysis. The reaction was performed under mild conditions and with good functional group tolerance. Various nine- to eleven-membered can be afforded moderate high yields (up 98%) enantioselectivities 93% ee). utilization both Z-linear dipole precursor binary catalyst is critical for the desired reactivity.

Language: Английский

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Enantioselective Formal 1,2-Diamination of Ketenes with Iminosulfinamides: Asymmetric Synthesis of Unnatural α,α-Disubstituted α-Amino Acid Derivatives

Organic Letters, Journal Year: 2024, Volume and Issue: 26(16), P. 3447 - 3452

Published: April 11, 2024

A method was developed for the enantioselective formal 1,2-diamination of disubstituted ketenes using iminosulfinamides as nitrogen sources. The protocol involves addition lithium to form N-iminosulfinyl amide metalloenolates. These metalloenolates then undergo a [2,3]-sigmatropic rearrangement yield unnatural α,α-disubstituted α-amino acid derivatives with high enantiopurity. chirality present at sulfur atom in is effectively transferred α carbon resulting products, facilitating highly amination ketenes.

Language: Английский

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New Synthetic Approaches for the Construction of Enantioenriched Molecules Bearing Quaternary Stereocenters

Advanced Synthesis & Catalysis, Journal Year: 2024, Volume and Issue: 366(21), P. 4294 - 4322

Published: Aug. 17, 2024

Abstract Optically active molecule architectures stand as an important class of organic compounds and occupy a key role in academic industrial communities. Particularly, the molecules bearing quaternary carbon are vital importance because its favorable conformation valuable three‐dimensional molecules, which frequently play broad spectrum functional materials, pharmaceutical relevant natural agrochemicals. Over past few decades, large number synthetic strategies for enantioselective construction with chiral centers have been focus research initiatives. In this review, state‐of‐the‐art toward synthesis enantioenriched stereocenters summarized, could be segmented into four categories: 1) Construction optically by addition to prochiral sp 2 carbon; 2) all‐carbon via substitution at non‐chiral tetra‐substituted 3) kinetic resolution; 4) desymmetrization reactions.

Language: Английский

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Interception of Transient anti-Allyl–Ir Species with Cu–Azomethine Ylide: Mechanistic Origins of Z-Selectivity in an Asymmetric Allylation Reaction

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(18), P. 14161 - 14171

Published: Sept. 10, 2024

Language: Английский

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Rhodium-Catalyzed Synthesis of Trifluoromethyl-Containing Allylic Alcohols Via Z-Alkenyl Transfer with High Stereochemistry Retention

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 9, 2024

Herein, we report the rhodium-catalyzed

Language: Английский

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Notizen aus der Chemie

Nachrichten aus der Chemie, Journal Year: 2024, Volume and Issue: 72(4), P. 48 - 51

Published: March 29, 2024

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