Chiral Aldehyde/Palladium Catalysis Enables Asymmetric Branched-Selective Ring-Opening Functionalization of Methylenecyclopropanes with Amino Acid Esters

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 10, 2025

Achieving catalytic asymmetric functionalization of methylenecyclopropanes (MCPs) by selective C–C bond cleavage is a notable challenge due to the intricate reaction partners involved. In this work, we report that chiral aldehyde/palladium combined catalysis enables MCPs with NH2-unprotected amino acid esters. This proceeds through regiospecific branched ring-opening mechanism, resulting in optically active α,α-disubstituted α-amino esters bearing nonconjugated terminal alkene units. Mechanism studies indicate pathways are irreversible and ultimate regioselectivity governed palladium catalysis. The products can be utilized construction dihydropyrazoles, α-methyl aspartic derivatives, analogues VPC01091 BMS-986104.

Language: Английский

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Copper-catalyzed intermolecular Regio- and Enantioselective Hydrosilylation of Alkenes with Prochiral Silanes

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 3, 2025

This study presents a copper-catalyzed, substrate-controlled regio- and enantioselective intermolecular hydrosilylation method capable of accommodating broad scope alkenes prochiral silanes. The approach offers an efficient versatile pathway to generate enantioenriched linear branched alkyl-substituted Si-stereogenic Key features this reaction include mild conditions, simple catalytic systems, compatibility with diverse substrates, high yields enantioselectivities. While methods create chiral carbon centers stereochemically defined silicon have been developed, the ability both simultaneously would be value. Here authors present substratecontrolled

Language: Английский

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Enantioselective 1,4-Borylamination via Copper-Catalyzed Cascade Hydroborylation and Hydroamination of Arylidenecyclopropanes

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(47), P. 32283 - 32291

Published: Nov. 13, 2024

Compounds bearing both boryl and amino groups at distal positions are invaluable synthons for synthesizing pharmaceuticals, drug candidates, natural products, but their catalytic enantioselective synthesis remains rarely explored. We report the first 1,4-borylamination reaction through a copper-catalyzed cascade hydroborylation hydroamination of arylidenecyclopropanes. This combines four readily available components in highly chemo-, site-, fashion (>20:1 r.r. up to 99% ee), yielding diverse array synthetically valuable enantioenriched 4-amino alkylboronates. The versatile utility these products is highlighted by transformations wide applications pharmaceutical discovery. Preliminary mechanistic studies were conducted elucidate operative pathway, intermediates, origins its high chemo- site-selectivity.

Language: Английский

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Enantioselective Pd- and Cu-Catalyzed Hydrofunctionalization of Methylenecyclopropanes via a Distal C–C Bond Cleavage

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

The enantioselective ring-opening reactions of methylenecyclopropanes (MCPs) involving C–C bond activation via oxidative addition transition metals have been rarely reported. Here, we disclose a Pd/Cu-catalyzed enantio- and regioselective coupling between cyclic imino esters MCPs to produce α-allylated 2H-pyrrole derivatives. In this reaction, azomethine ylide formed by chiral copper catalyst with ketimine ester would serve as nucleophile react activated palladium catalysis. This bimetallic system exhibited broad substrate scope high regio- enantioselectivities.

Language: Английский

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Ligand-Controlled Enantioselective Copper-Catalyzed Hydroboration and Ring-Opening Dihydroboration of Arylidenecyclobutanes

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: March 25, 2025

Arylidenecyclobutanes are readily accessible and versatile reagents in synthetic chemistry due to the multifaceted reactivity exhibited by their alkene strained cyclobutane moieties. However, metal-catalyzed enantioselective functionalization of arylidenecyclobutanes, particularly controllable ring-retaining ring-opening reactions, is rarely explored. Considering utility enantioenriched organoboronate compounds, herein we report ligand-controlled copper-catalyzed hydroboration dihydroboration reactions arylidenecyclobutanes that afford chiral α-cyclobutyl benzylboronate 1,5-diboronate compounds with high enantioselectivity when (S)-DTBM-Segphos (S,S)-Ph-BPE employed, respectively. Mechanistic studies reveal process via β-C elimination significantly slower than arylidenecyclopropanes presence CuOAc (S,S)-Ph-BPE. The these two protocols further demonstrated through conducting various stereospecific site-selective transformations organoboron products, including concise synthesis bioactive molecules.

Language: Английский

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Cobalt-Catalyzed Regioselective Intramolecular Hydrosilylation of Olefins to Access Sila-heterocycles

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: April 25, 2025

An efficient and straightforward cobalt-catalyzed regioselective intramolecular hydrosilylation of olefins has been developed. Regioselectivity is controlled by the choice ligands substrates, which operate through two distinct mechanisms. This method successfully applied to both terminal internal alkenes phenyl alkyl tethers between silane alkene, demonstrating its versatility across a broad range substrates.

Language: Английский

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Boron Catalysis-Enabled Regioselective Ring-Retentive Hydrosilylation of Methylenecyclopropanes

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 27, 2025

Herein, we report the highly regioselective ring-retentive hydrosilylation of methylenecyclopropanes (MCPs) with hydrosilanes by a B(C6F5)3 catalyst. The catalytic protocol affords an atom-efficient route for synthesis silylcyclopropanes, featuring 100% atom-efficiency, broad substrate scope (42 examples), mild conditions, and high regio-, chemoselectivity. current metal-free also provides complementary pathway structurally diverse organosilicon compounds from MCPs over transition metal-catalyzed variants.

Language: Английский

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Pd-Catalyzed Hydrocyanation of Methylenecyclopropanes: A Highly Selective Ring-Opening Access to 2-Substituted Allylic Nitriles

Organic Letters, Journal Year: 2024, Volume and Issue: 26(44), P. 9431 - 9435

Published: Oct. 30, 2024

Transition-metal-catalyzed hydrofunctionalization of methylenecyclopropanes presents a useful but challenging transformation due to the complex selectivity and multiple reaction pathways. We describe herein an unprecedented highly efficient selective palladium-catalyzed hydrocyanation give various 2-substituted allylic nitriles. Mechanistic studies demonstrated that may undergo Markovnikov-type hydrometalation β-carbon elimination.

Language: Английский

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