Ligand‐Free Copper‐Catalyzed 1,6‐Conjugate Reaction of para‐Quinone Methides with gem‐Diborylalkanes DOI

Jing He,

Deyuan Meng,

Dong Yeon Lee

et al.

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(47)

Published: Nov. 28, 2022

Abstract We report a ligand‐free copper‐catalyzed 1,6‐addition of α‐borylalkyl copper species, catalytically generated from gem ‐diborylalkanes to para ‐quinone methides. The reaction proceeds with good yield for variety methides and substituted catalytic amount CuI as catalyst. This system provides cost‐effective process functional group tolerance under mild conditions.

Language: Английский

Boron Ylide Enables Stereoselective Construction of gem‐Diborylcyclopropanes DOI

Tongchang Fang,

Peng Zhang,

Chao Liu

et al.

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 20, 2024

Abstract The stereoselective cyclopropanation of olefins with “boron ylide” is disclosed for the first time, providing a modular strategy synthesis stereospecific diboryl‐functionalized cyclopropanes. chiral gem ‐diborylcyclopropanes are synthesized excellent enantioselectivity aid auxiliary. Based on powerful transformable ability boryl group, those challenging multi‐quaternary carbon centers in cyclopropane units have been facilely constructed stereoselectivity. Control experiments indicate that groups necessary both chemoselectivity and stereoselectivity control.

Language: Английский

Citations

8
The current utility and future potential of multiborylated alkanes DOI

Kane A. C. Bastick,

Dean D Roberts,

Allan J. B. Watson

et al.

Nature Reviews Chemistry, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 26, 2024

Language: Английский

Citations

5
Generation and Application of Homoallylic α,α‐Diboryl Radicals via Diboron‐Promoted Ring‐Opening of Vinyl Cyclopropanes: cis‐Diastereoselective Borylative Cycloaddition** DOI Creative Commons
Het Vyas, Ashvin J. Gangani,

Aiswarya Mini

et al.

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 30(2)

Published: Oct. 4, 2023

Abstract Carbon‐centered radicals stabilized by adjacent boron atoms are underexplored reaction intermediates in organic synthesis. This study reports the development of vinyl cyclopropyl diborons (VCPDBs) as a versatile source previously unknown homoallylic α,α‐diboryl via thiyl radical catalyzed diboron‐directed ring opening. These diboryl underwent smooth [3+2] cycloaddition with variety olefins to provide cyclopentanes good excellent diastereoselectivity. In contrast trans ‐diastereoselectivity observed most dicarbonyl activated VCPs, VCPDBs showed remarkable preference for formation cis ‐cyclopentane diastereomer which was confirmed quantitative NOE and 2D NOESY studies. The ‐stereochemistry cyclopentane products enabled concise intramolecular Heck approach rare tricyclic cyclopentanoid framework containing diboron group. mild conditions also allowed one‐pot VCP ring‐opening, cycloaddition‐oxidation sequence afford disubstituted cyclopentanones. Control experiments DFT analysis mechanism support mediated pathway rationale To authors’ knowledge, these first examples use geminal group an activator opening α‐boryl radicals.

Language: Английский

Citations

8
Synthesis of Quaternary and Tertiary Carbon‐Substituted Arenes by Lewis Base Promoted Site‐Selective Coupling with Allylic Nucleophiles DOI

Hawa Keita,

Simon J. Meek

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(34)

Published: June 24, 2023

A practical method for the preparation of quaternary and tertiary allyl-substituted heteroarenes by site-selective couplings heteroaryl nitriles allylic nucleophiles is disclosed. Transformations utilize readily accessible stable reagents, proceed in presence a Lewis base activator, undergo aryl-C(sp

Language: Английский

Citations

8
Boron-Promoted Deprotonative Conjugate Addition: Geminal Diborons as Soft Pronucleophiles and Acyl Anion Equivalents DOI
Lucia Wang, Sheng‐Jia Lin,

Emmanuel Santos

et al.

The Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 87(15), P. 9896 - 9906

Published: July 12, 2022

Conjugate addition of α-boron-stabilized carbanions is an underexplored reaction modality. Existing methods require deborylation geminal di-/triboryl alkanes and/or the presence additional activating groups. We report 1,4-addition α,α-diboryl generated via deprotonation corresponding diborons. The methodology provided a general route to highly substituted and synthetically useful γ,γ-diboryl ketones. development diborons as soft pronucleophiles also enabled their use acyl anion equivalents one-pot tandem conjugate addition–oxidation sequence.

Language: Английский

Citations

10
Boron Ylide Enables Stereoselective Construction of gem‐Diborylcyclopropanes DOI

Tongchang Fang,

Peng Zhang,

Chao Liu

et al.

Angewandte Chemie, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 20, 2024

Abstract The stereoselective cyclopropanation of olefins with “boron ylide” is disclosed for the first time, providing a modular strategy synthesis stereospecific diboryl‐functionalized cyclopropanes. chiral gem ‐diborylcyclopropanes are synthesized excellent enantioselectivity aid auxiliary. Based on powerful transformable ability boryl group, those challenging multi‐quaternary carbon centers in cyclopropane units have been facilely constructed stereoselectivity. Control experiments indicate that groups necessary both chemoselectivity and stereoselectivity control.

Language: Английский

Citations

1
Ligand Enabled Manganese‐Catalyzed Oxidation of 1,2‐Disubstituted Cyclobutanols DOI

Ulada Karotsina,

Margarita Pilicheva,

Alaksiej L. Hurski

et al.

ChemistrySelect, Journal Year: 2024, Volume and Issue: 9(32)

Published: Aug. 22, 2024

Abstract Here we report a protocol for the preparation of 1,4‐diketones from 1,2‐disubstituted cyclobutanols based on their ring‐opening oxidation with molecular oxygen. The reaction proceeds under manganese catalysis in presence 1,10‐phenanthroline ligand and leads to target product along minor 4‐hydroxyketone that can be oxidized Dess‐Martin periodinane same vessel. Substrates alkyl aryl substituents including those bearing functional groups were successfully engaged reaction.

Language: Английский

Citations

0
Synthesis of Quaternary and Tertiary Carbon‐Substituted Arenes by Lewis Base Promoted Site‐Selective Coupling with Allylic Nucleophiles DOI

Hawa Keita,

Simon J. Meek

Angewandte Chemie, Journal Year: 2023, Volume and Issue: 135(34)

Published: June 24, 2023

Abstract A practical method for the preparation of quaternary and tertiary allyl‐substituted heteroarenes by site‐selective couplings heteroaryl nitriles allylic nucleophiles is disclosed. Transformations utilize readily accessible stable reagents, proceed in presence a Lewis base activator, undergo aryl‐C(sp 3 ) carbon formation with high γ‐selectivity (up to >98 : 2 γ α).

Language: Английский

Citations

0
Generation and Application of alpha,alpha-diboryl Radicals via Thiyl Radical Catalyzed Ring Opening of Vinyl Cyclopropyl Diborons: cis-Diastereoselective Borylative Cycloaddition with Alkenes DOI Creative Commons
Het Vyas, Ashvin J. Gangani,

Aiswarya Mini

et al.

Published: Aug. 24, 2023

Carbon-centered radicals stabilized by adjacent boron atoms are underexplored reaction intermediates in organic synthesis. We report the development of vinyl cyclopropyl diborons (VCPDBs) as a versatile source homoallylic a,a-diboryl via thiyl radical catalyzed diboron-directed ring opening. The diboryl carbon-centered underwent smooth [3+2] cycloaddition with variety olefins to provide highly substituted cyclopentanes good excellent diastereoselec- tivity. In contrast trans-diastereoselectivity observed most dicarbonyl activated VCPs, VCPDBs showed remarkable preference for formation cis-cyclopentane diastereomer which was confirmed quantitative NOE and 2D NOESY studies. cis-stereochemistry cyclopentane products enabled concise intramolecular Heck approach rare tricyclic cyclopentanoid frameworks. mild conditions also allowed one-pot VCP ring-opening, cy- cloaddition-oxidation sequence afford disubstituted cyclopentanones. Control experiments DFT analysis mecha- nism support mediated pathway rationale diastereoselectivity. To our knowledge, these first examples use geminal diboron group activator opening C-C bond a,a- radicals.

Language: Английский

Citations

0
Ligand‐Free Copper‐Catalyzed 1,6‐Conjugate Reaction of para‐Quinone Methides with gem‐Diborylalkanes DOI

Jing He,

Deyuan Meng,

Dong Yeon Lee

et al.

European Journal of Organic Chemistry, Journal Year: 2022, Volume and Issue: 2022(47)

Published: Nov. 28, 2022

Abstract We report a ligand‐free copper‐catalyzed 1,6‐addition of α‐borylalkyl copper species, catalytically generated from gem ‐diborylalkanes to para ‐quinone methides. The reaction proceeds with good yield for variety methides and substituted catalytic amount CuI as catalyst. This system provides cost‐effective process functional group tolerance under mild conditions.

Language: Английский

Citations

0