European Journal of Organic Chemistry, Год журнала: 2022, Номер 2022(47)
Опубликована: Ноя. 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.
Язык: Английский
Angewandte Chemie International Edition, Год журнала: 2024, Номер unknown
Опубликована: Сен. 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.
Язык: Английский
Процитировано
8
Nature Reviews Chemistry, Год журнала: 2024, Номер unknown
Опубликована: Сен. 26, 2024
Язык: Английский
Процитировано
5
Chemistry - A European Journal, Год журнала: 2023, Номер 30(2)
Опубликована: Окт. 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.
Язык: Английский
Процитировано
8
Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(34)
Опубликована: Июнь 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
Язык: Английский
Процитировано
8
The Journal of Organic Chemistry, Год журнала: 2022, Номер 87(15), С. 9896 - 9906
Опубликована: Июль 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.
Язык: Английский
Процитировано
10
Angewandte Chemie, Год журнала: 2024, Номер unknown
Опубликована: Сен. 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.
Язык: Английский
Процитировано
1
ChemistrySelect, Год журнала: 2024, Номер 9(32)
Опубликована: Авг. 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.
Язык: Английский
Процитировано
0
Angewandte Chemie, Год журнала: 2023, Номер 135(34)
Опубликована: Июнь 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).
Язык: Английский
Процитировано
0
Опубликована: Авг. 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.
Язык: Английский
Процитировано
0
European Journal of Organic Chemistry, Год журнала: 2022, Номер 2022(47)
Опубликована: Ноя. 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.
Язык: Английский
Процитировано
0